JP2004355960A - Semiconductor for photoelectric conversion material, photoelectric conversion device, and solar cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor for photoelectric conversion materials, a photoelectric conversion device and a solar cell, which have high efficiency of photoelectric conversion and excellent stability. <P>SOLUTION: This semiconductor for photoelectric conversion materials is characterized by containing a coloring matter represented by the general formula (1):Q-B<SB>1</SB>=B<SB>2</SB>-A(wherein A represents a 5-6 membered aromatic group or a heterocyclic group; B<SB>1</SB>and B<SB>2</SB>each represent -CR<SB>1</SB>= or -N=, and at least one thereof represent -N=; R<SB>1</SB>represents a hydrogen atom or substituent; and Q represents an atom group having, in the molecule, at least one carboxyl group). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００５４】
【化７】

【００５５】
以下に、上記一般式（Ｃｐ−１）〜（Ｃｐ−１８）で表される原子団について詳しく説明する。
【００５６】
《一般式（Ｃｐ−１）、（Ｃｐ−２）で表される原子団》
一般式（Ｃｐ−１）、（Ｃｐ−２）において、Ｒ_６２は水素原子、アルキル基、アリール基、複素環基、アシル基を表し、Ｒ_６３、Ｒ_６４はそれぞれ、水素原子、アルキル基、アルケニル基、アリール基、複素環基、アシルアミノ基、アルキルスルホニルアミノ基、アリールスルホニルアミノ基、アミノ基、アルキルアミノ基、アルキルチオ基、アリールチオ基、アルコキシル基、アリールオキシ基、ウレイド基、アルコキシカルボニルアミノ基、カルバモイル基、カルボキシル基またはアルコキシカルボニル基を表す。
【００５７】
式中、Ｒ_６２で表される基としては、好ましくは、水素原子、アルキル基、アシル基が挙げられる。
【００５８】
式中、Ｒ_６３で表される基としては、好ましくは、アルキル基、アリール基、カルボキシル基、アルコキシル基、カルバモイル基が挙げられるが、更に好ましくは、メチル基、ｔｅｒｔ−ブチル基、カルボキシル基である。
【００５９】
式中、Ｒ_６４で表される基としては、好ましくは、アルキル基、アルケニル基、アリール基である。
【００６０】
《一般式（Ｃｐ−３）、（Ｃｐ−４）で表される原子団》
一般式（Ｃｐ−３）、（Ｃｐ−４）において、Ｒ_６２、Ｒ_６３及びＲ_６４は、前記一般式（Ｃｐ−１）、（Ｃｐ−２）に記載のＲ_６２、Ｒ_６３及びＲ_６４と同義である。
【００６１】
Ｒ_６５及びＲ_６７は、それぞれ、水素原子、アルキル基、アリール基、複素環基、アシルアミノ基、アルキルスルホニルアミノ基、アリールスルホニルアミノ基、アミノ基、アルキルチオ基、アリールチオ基、アルコキシル基、アリールオキシ基、ウレイド基、アルコキシカルボニルアミノ基、アシル基、カルボキシル基、アルコキシカルボニル基またはカルバモイル基を表す。
【００６２】
式中、Ｒ_６５で表される基としては、好ましくは、アルキル基、アリール基、アルコキシル基、アリールオキシ基等が挙げられ、Ｒ_６３、Ｒ_６４、Ｒ_６７で、それぞれ表される基としては、好ましくは、水素原子、アルキル基、アリール基、カルボキシル基、アルコキシカルボニル基、カルバモイル基が挙げられる。
【００６３】
《一般式（Ｃｐ−５）で表される原子団》
一般式（Ｃｐ−５）において、Ｒ_６８及びＲ_６９はそれぞれ、水素原子、アルキル基、アリール基、複素環基、アシルアミノ基、アルキルスルホニル基、アリールスルホニルアミノ基、アミノ基、アルキルチオ基、アリールチオ基、アルコキシル基、アリールオキシ基、ウレイド基、アルコキシカルボニルアミノ基、カルボキシル基、アシル基、アルコキシカルボニル基またはカルバモイル基を表す。
【００６４】
一般式（Ｃｐ−５）において、Ｒ_６２は、前記一般式（Ｃｐ−１）、（Ｃｐ−２）に記載のＲ_６２と同義である。
【００６５】
式中、Ｒ_６８、Ｒ_６９で表される基としては、好ましくは、それぞれ水素原子、アルキル基、アリール基、カルボキシル基等が挙げられる。
【００６６】
《一般式（Ｃｐ−６）〜（Ｃｐ−１０）で表される原子団》
一般式（Ｃｐ−６）〜（Ｃｐ−１０）において、Ｒ_８７、Ｒ_８８は、それぞれ水素原子、アルキル基、アリール基、複素環基、カルバモイル基、アルコキシカルボニル基、アリールオキシカルボニル基、カルボキシル基、シアノ基、スルファモイル基、アルキルスルホニル基、アリールスルホニル基またはニトロ基を表し、Ｒ_８９、Ｒ_９０はそれぞれ水素原子、カルボキシル基、アルキル基、アリール基または複素環基を表し、Ｒ_６２は、前記一般式（Ｃｐ−１）、（Ｃｐ−２）に記載のＲ_６と同義である。
【００６７】
式中、Ｒ_８７で表される基としては、好ましくは、カルバモイル基、アルコキシカルボニル基、カルボキシル基、シアノ基等がであり、更に好ましくは、カルボキシル基、シアノ基である。Ｒ_８８で表される基としては、カルバモイル基、カルボキシル基、アルコキシカルボニル基、シアノ基、アルキルスルホニル基、アリールスルホニル基等であり、更に好ましくは、アルコキシカルボニル基、カルボキシル基等である。Ｒ_８９、Ｒ_９０で、それぞれ表される基としては、好ましくは、アルキル基、アリール基等であり、更に好ましくは、アリール基である。
【００６８】
《一般式（Ｃｐ−１１）〜（Ｃｐ−１８）で表される原子団》
一般式（Ｃｐ−１１）〜（Ｃｐ−１８）において、Ｒ_９１、Ｒ_９２は、それぞれアルキル基、アリール基、複素環基、カルバモイル基、アルコキシカルボニル基、アリールオキシカルボニル基、カルボキシル基、シアノ基、スルファモイル基、アルキルスルホニル基、アリールスルホニル基またはニトロ基を表し、Ｒ_９３、Ｒ_９４、Ｒ_９５は、それぞれ水素原子、アルキル基、アリール基、複素環基、アシルアミノ基、ウレイド基、アルコキシカルボニルアミノ基、アルキルまたはアリールスルホニルアミノ基、ハロゲン原子、カルボキシル基、アミノ基、アルキルチオ基、アリールチオ基、アルコキシル基またはアリールオキシ基を表し、Ｒ_６２は、前記一般式（Ｃｐ−１）、（Ｃｐ−２）に記載のＲ_６と同義である。
【００６９】
式中、Ｒ_９１で表される基としては、好ましくは、アリール基、複素環基、カルバモイル基、アルコキシカルボニル基、カルボキシル基、シアノ基等であり、Ｒ_９２で表される基としては、好ましくは、カルバモイル基、アルコキシカルボニル基、カルボキシル基、シアノ基、スルファモイル基ま、アルキルスルホニル基、アリールスルホニル基等であり、Ｒ_９３、Ｒ_９４、Ｒ_９５でそれぞれ表される基としては、好ましくは、水素原子、アルキル基、アシルアミノ基、ハロゲン原子、カルボキシル基、アミノ基、アルキルチオ基、アリールチオ基等が挙げられる。
【００７０】
また、Ｑは好ましくは下記一般式ａ〜ｄで表されることが好ましい。
【００７１】
【化８】

【００７２】
一般式ａ〜ｄにおいて、Ｒ_４′及びＲ_５′は水素原子または置換基を表し、Ｚ_２は５または６員環を形成するために必要な原子団を表わし、置換基を有していてもよく、置換基で結合し縮環を形成してもよく、＊でＱ以外の部分と結合する。また、少なくとも１つはカルボキシル基を有している。Ｒ_４′及びＲ_５′の置換基は前述した置換基と同義である。Ｒ_６′は水素原子、アルキル基またはアシル基である。
【００７３】
Ｚ_２を更に具体的に説明すると例えば、一般式ａの場合は下記一般式ａ−１〜ａ−９等で表される化合物等が挙げられる。
【００７４】
【化９】

【００７５】
一般式ａ−１〜ａ−３、ａ−６〜ａ−９は前述した一般式（Ｃｐ−１）〜（Ｃｐ−３）、（Ｃｐ−１５）〜（Ｃｐ−１８）と同一の化合物であり、一般式ａ−４及びａ−５におけるＲ_４′、Ｒ_５′、Ｒ_６′はそれらと同義である。
【００７６】
Ｒ_４′〜Ｒ_７′はそれぞれ水素原子または置換基を表し、ａ−１、ａ−２、ａ−３、ａ−６及びａ−７の構造が好ましく、更に好ましくはａ−１、ａ−３及びａ−６である。
【００７７】
一般式ｂ〜ｄにおいても同様の構造を持つ化合物が挙げられる。例えば、一般式ｂは一般式（Ｃｐ−８）、（Ｃｐ−１０）、（Ｃｐ−１２）及び（Ｃｐ−１４）が、一般式ｃは一般式（Ｃｐ−６）、（Ｃｐ−７）、（Ｃｐ−９）、（Ｃｐ−１１）及び（Ｃｐ−１３）が、一般式ｄは一般式（Ｃｐ−４）〜（Ｃｐ−５）等が挙げられるがこれらに限定されることはない。
【００７８】
一般式（Ｃｐ−１）〜（Ｃｐ−１８）において好ましい構造としては、（Ｃｐ−１）、（Ｃｐ−２）、（Ｃｐ−３）、（Ｃｐ−４）、（Ｃｐ−６）、（Ｃｐ−７）、（Ｃｐ−８）、（Ｃｐ−１１）、（Ｃｐ−１２）、（Ｃｐ−１５）及び（Ｃｐ−１６）が挙げられるが、更に好ましくは（Ｃｐ−１）、（Ｃｐ−２）、（Ｃｐ−３）、（Ｃｐ−４）、（Ｃｐ−６）及び（Ｃｐ−１５）である。
【００７９】
次に一般式（６）について説明する。一般式（Ｃｐ−１）〜（Ｃｐ−３）におけるＲ６４が一般式（６）で表されることが好ましい。
【００８０】
一般式（６）において、Ｒ_９またはＲ_１０は水素原子または置換基を表し、ｎは０〜３の整数を表し、ｎが１以上の場合はＲ_９とＲ_１０が結合し５〜６員環を形成してもよい。ここで言う置換基は一般式（１）の置換基と同義である。
【００８１】
Ｒ_９とＲ_１０の置換基は、具体的にはアルキル基、シクロアルキル基、ハロゲン原子、カルボキシル基、アルコキシカルボニル基等が挙げられるが、Ｒ_９とＲ_１０は水素原子、アルキル基が更に好ましい。ｎは好ましくは０〜２であり、更に好ましくは０〜１である。
【００８２】
以下に、本発明に係る前記一般式（１）で表される化合物の具体例を示すが、本発明は、これらに限定されない。
【００８３】
【化１０】

【００８４】
【化１１】

【００８５】
【化１２】

【００８６】
【化１３】

【００８７】
【化１４】

【００８８】
【化１５】

【００８９】
【化１６】

【００９０】
【化１７】

【００９１】
【化１８】

【００９２】
【化１９】

【００９３】
【化２０】

【００９４】
【化２１】

【００９５】
【化２２】

【００９６】
【化２３】

【００９７】
【化２４】

【００９８】
【化２５】

【００９９】
【化２６】

【０１００】
【化２７】

【０１０１】
【化２８】

【０１０２】
【化２９】

【０１０３】
【化３０】

【０１０４】
【化３１】

【０１０５】
【化３２】

【０１０６】
【化３３】

【０１０７】
【化３４】

【０１０８】
【化３５】

【０１０９】
【化３６】

【０１１０】
【化３７】

【０１１１】
【化３８】

【０１１２】
【化３９】

【０１１３】
【化４０】

【０１１４】
【化４１】

【０１１５】
【化４２】

【０１１６】
【化４３】

【０１１７】
【化４４】

【０１１８】
【化４５】

【０１１９】
【化４６】

【０１２０】
【化４７】

【０１２１】
【化４８】

【０１２２】
【化４９】

【０１２３】
【化５０】

【０１２４】
【化５１】

【０１２５】
【化５２】

【０１２６】
【化５３】

【０１２７】
【化５４】

【０１２８】
【化５５】

【０１２９】
本発明に係る前記一般式（１）で表される化合物は、例えば特開平５−１７７９５８号、同１０−２６５６９０号、同１１−１８９７２８号、同９−２２０８６１号、特開２００１−２７９１２３号等に記載された従来公知の方法を参考にして合成することができる。
【０１３０】
以下に具体的に合成法の一例を示すが、その他の化合物も同様にして合成することが可能であり、合成法としては、これらに限定されない。
【０１３１】
（例示化合物Ｉ−１の合成）
以下に記載の合成ルートに従い、例示化合物Ｉ−１を合成した。
【０１３２】
（１）合成ルート
【０１３３】
【化５６】

【０１３４】
（２）例示化合物Ｉ−１の合成
５．２４ｇの中間体１にエタノール６０ｍｌ及び３．９２ｇの中間体２を加え３時間加熱還流反応させる。反応終了後冷却する。析出する結晶をろ過し、酢酸エチルで洗浄し、７．１８ｇの例示化合物Ｉ−１を得た。ＭＡＳＳ、Ｈ−ＮＭＲ、ＩＲスペクトルによって同定し、目的物であることを確認した。
【０１３５】
（例示化合物ＩＩＩ−１の合成）
以下に記載の合成ルートに従い、例示化合物ＩＩＩ−１を合成した。
【０１３６】
（１）合成ルート
【０１３７】
【化５７】

【０１３８】
（２）例示化合物ＩＩＩ−１の合成
２．３４ｇの中間体３にメタノール５０ｍｌ、トリエチルアミン７ｍｌを加え５℃まで冷却する。別途調整した２．４８ｇの中間体４の水懸濁液を１０℃以下で３０分掛け滴下し、反応させる。反応終了後室温にし析出する結晶をろ過し、アセトニトリルで再結晶し、２．６３ｇの例示化合物ＩＩＩ−１を得た。ＭＡＳＳ、Ｈ−ＮＭＲ、ＩＲスペクトルによって同定し、目的物であることを確認した。
【０１３９】
《光電変換材料用半導体の増感処理》
本発明の光電変換材料用半導体は、前記一般式（１）で表される化合物を含むことにより増感し、本発明に記載の効果を奏することが可能となる。ここで、化合物を含むとは、半導体表面への吸着、半導体が多孔質等のポーラスな構造を有する場合には、半導体の多孔質構造に前記化合物が入りこむ等の種々の態様が挙げられる。また、半導体層（半導体でもよい）１ｍ^２当たりの前記一般式（１）で表される化合物の総含有量は０．０１〜１００ミリモルの範囲が好ましく、更に好ましくは０．１〜５０ミリモル、特に好ましくは、０．５〜２０ミリモルである。
【０１４０】
本発明に係る前記一般式（１）で表される化合物を用いて増感処理を行う場合、前記化合物を単独で用いてもよいし、複数を併用することも、本発明に係る前記一般式（１で表される化合物と他の化合物（例えば、米国特許第４，６８４，５３７号、同第４，９２７，７２１号、同第５，０８４，３６５号、同第５，３５０，６４４号、同第５，４６３，０５７号、同第５，５２５，４４０号等の各明細書、特開平７−２４９７９０号、特開２０００−１５０００７号等に記載の化合物）とを混合して用いることもできる。
【０１４１】
特に、本発明の光電変換材料用半導体の用途が、後述する太陽電池である場合には、光電変換の波長域をできるだけ広くして太陽光を有効に利用できるように、吸収波長の異なる二種類以上の色素を混合して用いることが好ましい。
【０１４２】
半導体に、前記一般式（１）で表される化合物を含ませるには、前記化合物を適切な溶媒（エタノール等）に溶解し、その溶液中によく乾燥した半導体を長時間浸漬する方法が一般的である。
【０１４３】
前記一般式（１）で表される化合物を複数種類併用したり、その他の増感色素化合物とを併用した光電変換材料用半導体を作製する際には、各々の化合物の混合溶液を調製して用いてもよいし、それぞれの化合物について溶液を用意して、各溶液に順に浸漬して作製することもできる。各化合物について別々の溶液を用意し、各溶液に順に浸漬して作製する場合は、半導体に前記化合物や増感色素等を含ませる順序がどのようであっても本発明に記載の効果を得ることができる。また、前記化合物を単独で吸着させた半導体微粒子を混合する等することにより作製してもよい。
【０１４４】
吸着処理は半導体が粒子状の時に行ってもよいし、支持体上に膜を形成した後に行ってもよい。吸着処理に用いる化合物を溶解した溶液は、それを常温で用いてもよいし、化合物が分解せず溶液が沸騰しない温度範囲で加熱して用いてもよい。また、後述する光電変換素子の製造のように、半導体微粒子の塗布後（感光層の形成後）に、前記化合物の吸着を実施してもよい。また、半導体微粒子と本発明の前記化合物とを同時に塗布することにより、前記化合物の吸着を実施してもよい。また、未吸着の化合物は洗浄によって除去することができる。
【０１４５】
また、本発明の光電変換材料用半導体の増感処理については、半導体を、前記一般式（１）で表される化合物を含むことにより増感処理が行われるが、増感処理の詳細については、後述する光電変換素子のところで具体的に説明する。
【０１４６】
また、空隙率の高い半導体薄膜を有する光電変換材料用半導体の場合には、空隙に水分、水蒸気等により水が半導体薄膜上、並びに半導体薄膜内部の空隙に吸着する前に、前記化合物や増感色素化合物等の吸着処理（光電変換材料用半導体の増感処理）を完了することが好ましい。
【０１４７】
本発明の光電変換材料用半導体は、有機塩基を用いて表面処理してもよい。前記有機塩基としては、ジアリールアミン、トリアリールアミン、ピリジン、４−ｔ−ブチルピリジン、ポリビニルピリジン、キノリン、ピペリジン、アミジン等が挙げられるが、中でも、ピリジン、４−ｔ−ブチルピリジン、ポリビニルピリジンが好ましい。
【０１４８】
上記の有機塩基が液体の場合はそのまま、固体の場合は有機溶媒に溶解した溶液を準備し、本発明の光電変換材料用半導体を液体アミンまたはアミン溶液に浸漬することで、表面処理を実施できる。
【０１４９】
また、本発明に係る前記一般式（１）で表される化合物と併用して用いることのできる色素としては、本発明に係る半導体を分光増感しうるものならばいずれの色素も用いることができる。光電変換の波長域をできるだけ広くし、かつ変換効率を上げるため、二種類以上の色素を混合することが好ましい。また、目的とする光源の波長域と強度分布に合わせるように、混合する色素とその割合を選ぶことができる。
【０１５０】
本発明に係る色素の中では、光電子移動反応活性、光耐久性、光化学的安定性等の総合的な観点から、金属錯体色素、フタロシアニン系色素、ポルフィリン系色素、ポリメチン系色素が好ましく用いられる。
【０１５１】
金属錯体色素の中では、特開２００１−２２３０３７号、同２００１−２２６６０７号、米国特許第４，９２７，７２１号、同第４，６８４，５３７号、同第５，０８４，３６５号、同第５，３５０，６４４号、同第５，４６３，０５７号、同第５，５２５，４４０号、特開平７−２４９７５０号、特表平１０−５０４５１２号、世界特許９８９／５０３９３号等に記載のルテニウム錯体色素が好ましく用いられる。
【０１５２】
ポルフィリン系色素、フタロシアニン系色素としては、特開２００１−２２３０３７号に記載の色素が好ましい色素として挙げられる。
【０１５３】
ポリメチン系色素としては、従来公知のメチン系色素、特開平１１−３５８３６号、同１１−１５８３９５号、同１１−１６３３７８号、同１１−２１４７３０号、同１１−２１４７３１号、同１０−９３１１８号、同１１−２７３７５４号、特開２０００−１０６２２４号、同２０００−３５７８０９号、同２００１−５２７６６号、欧州特許第８９２，４１１号、同９１１，８４１号等に記載のものが挙げられる。
【０１５４】
《光電変換材料用半導体の作製方法》
本発明の光電変換材料用半導体の作製方法について説明する。
【０１５５】
本発明の光電変換材料用半導体の一態様としては、導電性支持体上に上記の光電変換材料用半導体を焼成により形成する等の方法が挙げられる。
【０１５６】
本発明の光電変換材料用半導体が焼成により作製される場合には、上記の化合物や増感色素を用いての半導体の増感（吸着、多孔質への入り込み等）処理は、焼成後に実施することが好ましい。焼成後、半導体に水が吸着する前に、素早く化合物の吸着処理を実施することが特に好ましい。
【０１５７】
本発明の光電変換材料用半導体が粒子状の場合には、光電変換材料用半導体を導電性支持体に塗布または吹き付けて、半導体電極を作製するのがよい。また、本発明の光電変換材料用半導体が膜状であって、導電性支持体上に保持されていない場合には、光電変換材料用半導体を導電性支持体上に貼合して半導体電極を作製することが好ましい。
【０１５８】
以下、本発明の光電変換材料用半導体の作製工程を具体的に述べる。
《半導体微粉末含有塗布液の調製》
まず、半導体の微粉末を含む塗布液を調製する。この半導体微粉末は、その１次粒子径が微細な程好ましく、その１次粒子径は、１〜５０００ｎｍが好ましく、更に好ましくは２〜５０ｎｍである。半導体微粉末を含む塗布液は、半導体微粉末を溶媒中に分散させることによって調製することができる。溶媒中に分散された半導体微粉末は、その１次粒子状で分散する。溶媒としては、半導体微粉末を分散し得るものであればよく、特に制約されない。
【０１５９】
前記溶媒としては、水、有機溶媒、水と有機溶媒との混合液が包含される。有機溶媒としては、メタノールやエタノール等のアルコール、メチルエチルケトン、アセトン、アセチルアセトン等のケトン、ヘキサン、シクロヘキサン等の炭化水素等が用いられる。塗布液中には、必要に応じ、界面活性剤や粘度調節剤（ポリエチレングリコール等の多価アルコール等）を加えることができる。溶媒中の半導体微粉末濃度の範囲は、０．１〜７０質量％が好ましく、更に好ましくは０．１〜３０質量％である。
【０１６０】
《半導体微粉末含有塗布液の塗布と形成された半導体層の焼成処理》
上記のようにして得られた半導体微粉末含有塗布液を導電性支持体上に塗布または吹きつけ、乾燥等を行った後、空気中または不活性ガス中で焼成して、導電性支持体上に半導体層（半導体膜）が形成される。
【０１６１】
導電性支持体上に塗布液を塗布、乾燥して得られる皮膜は、半導体微粒子の集合体からなるもので、その微粒子の粒径は使用した半導体微粉末の１次粒子径に対応するものである。
【０１６２】
このようにして導電性支持体等の基板上に形成された半導体微粒子集合体膜は、導電性支持体との結合力や、微粒子相互の結合力が弱く、機械的強度の弱いものであることから、前記半導体微粒子集合体膜を焼成処理して機械的強度を高め、基板に強く固着した焼成物膜となるため好ましく行われる。
【０１６３】
本発明においては、この焼成物膜はどのような構造を有していてもよいが、多孔質構造膜（空隙を有する、ポーラスな層ともいう）であることが好ましい。
【０１６４】
ここで、本発明に係る半導体薄膜の空隙率は、１０体積％以下が好ましく、更に好ましくは、８体積％以下であり、特に好ましくは、０．０１〜５体積％である。なお、半導体薄膜の空隙率は、誘電体の厚み方向に貫通性のある空隙率を意味し、水銀ポロシメーター（島津ポアライザー９２２０型）等の市販の装置を用いて測定することができる。
【０１６５】
多孔質構造を有する焼成物膜になった、半導体層の膜厚は、少なくとも１０ｎｍ以上が好ましく、更に好ましくは１００〜１００００ｎｍである。
【０１６６】
焼成処理時、焼成物膜の実表面積を適切に調整し、上記の空隙率を有する焼成物膜を得る観点から、焼成温度は１０００℃より低いことが好ましく、更に好ましくは、２００〜８００℃の範囲であり、特に好ましくは３００〜８００℃の範囲である。
【０１６７】
また、見かけ表面積に対する実表面積の比は、半導体微粒子の粒径及び比表面積や、焼成温度等によりコントロールすることができる。また、加熱処理後、半導体粒子の表面積を増大させたり、半導体粒子近傍の純度を高め、色素から半導体粒子への電子注入効率を高める目的で、例えば四塩化チタン水溶液を用いた化学メッキや三塩化チタン水溶液を用いた電気化学的メッキ処理を行ってもよい。
【０１６８】
《半導体の増感処理》
半導体の増感処理は、上記のように、色素を適切な溶媒に溶解し、その溶液に前記半導体を焼成した基板を浸漬することによって行われる。その際には半導体層（半導体膜ともいう）を焼成により形成させた基板を、あらかじめ減圧処理したり加熱処理したりして膜中の気泡を除去し、前記一般式（１）〜（５）で表される化合物が半導体層（半導体膜）内部深くに進入できるようにしておくことが好ましく、半導体層（半導体膜）が多孔質構造膜である場合には特に好ましい。
【０１６９】
《溶媒》
前記一般式（１）で表される化合物を溶解するのに用いる溶媒は、前記化合物を溶解することができ、かつ、半導体を溶解したり半導体と反応したりすることのないものであれば格別の制限はないが、溶媒に溶解している水分及び気体が半導体膜に進入して、前記化合物の吸着等の増感処理を妨げることを防ぐために、あらかじめ脱気及び蒸留精製しておくことが好ましい。
【０１７０】
前記化合物の溶解において、好ましく用いられる溶媒はメタノール、エタノール、ｎ−プロパノール等のアルコール系溶媒、アセトン、メチルエチルケトン等のケトン系溶媒、ジエチルエーテル、ジイソプロピルエーテル、テトラヒドロフラン、１，４−ジオキサン等のエーテル系溶媒、塩化メチレン、１，１，２−トリクロロエタン等のハロゲン化炭化水素溶媒であり、特に好ましくはメタノール、エタノール、アセトン、メチルエチルケトン、テトラヒドロフラン、塩化メチレンである。
【０１７１】
《増感処理の温度、時間》
半導体を焼成した基板を、前記一般式（１）で表される化合物を含む溶液に浸漬する時間は、半導体層（半導体膜）に前記化合物が深く進入して吸着等を充分に進行させ、半導体を十分に増感させ、かつ、溶液中での前記化合物の分解等により生成して分解物が化合物の吸着を妨害することを抑制する観点から、２５℃条件下では、３〜４８時間が好ましく、更に好ましくは、４〜２４時間である。この効果は、特に、半導体膜が多孔質構造膜である場合において顕著である。但し、浸漬時間については、２５℃条件での値であり、温度条件を変化させて場合には、上記の限りではない。
【０１７２】
浸漬しておくに当たり前記一般式（１）で表される化合物を含む溶液は、前記化合物が分解しない限りにおいて、沸騰しない温度にまで加熱して用いてもよい。好ましい温度範囲は１０〜１００℃であり、更に好ましくは２５〜８０℃であるが、前記のとおり溶媒が前記温度範囲で沸騰する場合はこの限りでない。
【０１７３】
《光電変換素子》
本発明の光電変換素子について、図１を用いて説明する。
【０１７４】
図１は、本発明の光電変換素子の構造の一例を示す部分断面図である。
１は導電性支持体、２は感光層、３は電荷移動層、４は対向電極を表す。なお、導電性支持体１と感光層２をあわせて半導体電極ともいう。
【０１７５】
ここで、感光層２は本発明の光電変換材料用半導体を有する層であり、電荷移動層３は通常、レドックス電解質が含有し、導電性支持体１、感光層２、対向電極４に接触した形態で用いられる。
【０１７６】
《光電変換素子の製造方法》
図１を用いながら、光電変換素子の製造方法を説明する。
【０１７７】
本発明の光電変換素子は、図１に示すような導電性支持体１上に、上記記載のようにプラズマ処理装置を用いて半導体薄膜を形成した後に、本発明に係る前記一般式（１）で表される化合物を吸着させるという工程を経て製造される。
【０１７８】
また、半導体薄膜の表面積を増大させたり、半導体薄膜表面の不純物等を除去して、半導体の純度を高め、前記一般式（１）で表される化合物から半導体への電子注入効率を高める目的で、例えば四塩化チタン水溶液を用いた化学メッキや三塩化チタン水溶液を用いた電気化学的メッキ処理を行ってもよい。
【０１７９】
導電性支持体１上に形成した半導体膜には上記記載の前記一般式（１）で表される化合物を吸着させ、半導体膜を増感させて感光層２を形成する。増感処理方法は先に説明したとおり、前記化合物を適切な溶媒に溶解し、導電性支持体１上に形成された半導体膜をその溶液に浸漬することによって行われる。その際には半導体膜は、あらかじめ減圧処理したり加熱処理したりして膜中の気泡を除去し、前記一般式（１）で表される化合物が半導体膜内部深くに進入できるようにしておくことが好ましい。
【０１８０】
本発明に係る半導体に、前記一般式（１）で表される化合物を吸着させる際には、単独で用いてもよいし、複数を併用してもよい。さらに、従来公知の増感色素化合物（例えば、米国特許第４，６８４，５３７号、同第４，９２７，７２１号、同第５，０８４，３６５号、同第５，３５０，６４４号、同第５，４６３，０５７号、同第５，５２５，４４０号、特開平７−２４９７９０号、特開２０００−１５０００７号等に記載の化合物）とを混合して吸着させてもよい。
【０１８１】
特に、半導体の用途が太陽電池である場合、光電変換の波長域を広くして太陽光を可能な限り有効に利用できるように、二種類以上の色素を混合して用いることが好ましい。
【０１８２】
上記記載の前記一般式（１）で表される化合物を複数種類併用して増感した光電変換材料用半導体は、併用する前記化合物を混合して調製した溶液に浸漬させて作製してもよいし、各々の化合物について溶液を調製し、各溶液に順に浸漬して作製することもできる。
【０１８３】
各化合物について別々の溶液を用意し、各溶液に順に浸漬して作製する場合は、半導体に前記化合物や従来公知の増感色素を吸着させる順番がどのような順番であっても本発明の効果を得ることができる。
【０１８４】
吸着処理は、前記化合物が溶解した溶液を常温で用いてもよいし、また、前記化合物に影響を与えない範囲の温度まで溶液を加熱して行ってもよい。更に、吸着処理時に未吸着となった色素については溶媒等の洗浄処理により除去することが好ましい。
【０１８５】
導電性支持体１上に形成した半導体膜に色素を吸着させて感光層２を形成したら、感光層２と向かい合うようにして対向電極４を配置する。さらに、半導体電極と対向電極４の間に電荷移動層であるレドックス電解質を注入して光電変換素子とする。
【０１８６】
《太陽電池》
本発明の太陽電池について説明する。
【０１８７】
本発明の太陽電池は、図１に示すような、本発明の光電変換素子の一態様として、太陽光に最適の設計並びに、回路設計が行われ、太陽光を光源として用いたときに最適な光電変換が行われるような構造を有する。即ち、光電変換材料用半導体に太陽光が照射されうる構造となっている。本発明の太陽電池を構成する際には、前記半導体電極、電荷移動層及び対向電極をケース内に収納して封止するか、またはそれら全体を樹脂封止することが好ましい。
【０１８８】
本発明の太陽電池に太陽光または太陽光と同等の電磁波を照射すると、光電変換材料用半導体に吸着された本発明の化合物は、照射された光または電磁波を吸収して励起する。励起によって発生した電子は半導体に移動し、次いで導電性支持体１を経由して対向電極４に移動して、電荷移動層３のレドックス電解質を還元する。一方、半導体に電子を移動させた本発明の化合物は酸化体となっているが、対向電極４から電荷移動層３のレドックス電解質を経由して電子が供給されることにより、還元されて元の状態に戻り、同時に電荷移動層３のレドックス電解質は酸化されて、再び対向電極４から供給される電子により還元されうる状態に戻る。このようにして電子が流れ、本発明の光電変換素子を用いた太陽電池を構成することができる。
【０１８９】
《導電性支持体》
本発明の光電変換素子や本発明の太陽電池に用いられる導電性支持体には、金属板のような導電性材料や、ガラス板やプラスチックフイルムのような非導電性材料に導電性物質を設けた構造のものを用いることができる。導電性支持体に用いられる材料の例としては金属（例えば、白金、金、銀、銅、アルミニウム、ロジウム、インジウム）または導電性金属酸化物（例えば、インジウム−スズ複合酸化物、酸化スズにフッ素をドープしたもの）や炭素を挙げることができる。導電性支持体の厚さは特に制約されないが、０．３〜５ｍｍが好ましい。
【０１９０】
また導電性支持体は実質的に透明であることが好ましく、実質的に透明であるとは光の透過率が１０％以上であることを意味し、５０％以上であることがさらに好ましく、８０％以上であることが最も好ましい。透明な導電性支持体を得るためには、ガラス板またはプラスチックフイルムの表面に、導電性金属酸化物からなる導電性層を設けることが好ましい。透明な導電性支持体１を用いる場合、光は支持体側から入射させることが好ましい。
【０１９１】
導電性支持体は表面抵抗は、５０Ω／ｃｍ^２以下であることが好ましく、１０Ω／ｃｍ^２以下であることがさらに好ましい。
【０１９２】
《電荷移動層》
本発明に用いられる電荷移動層について説明する。
【０１９３】
電荷移動層にはレドックス電解質が好ましく用いられる。ここで、レドックス電解質としては、Ｉ⁻／Ｉ^３−系や、Ｂｒ⁻／Ｂｒ^３−系、キノン／ハイドロキノン系等が挙げられる。このようなレドックス電解質は、従来公知の方法によって得ることができ、例えば、Ｉ⁻／Ｉ^３−系の電解質は、ヨウ素のアンモニウム塩とヨウ素を混合することによって得ることができる。電荷移動層はこれらレドックス電解質の分散物で構成され、それら分散物は溶液である場合に液体電解質、常温において固体である高分子中に分散させた場合に固体高分子電解質、ゲル状物質に分散された場合にゲル電解質と呼ばれる。電荷移動層として液体電解質が用いられる場合、その溶媒としては、電気化学的に不活性なものが用いられ、例えば、アセトニトリル、炭酸プロピレン、エチレンカーボネート等が用いられる。固体高分子電解質の例としては特開２００１−１６０４２７記載の電解質が、ゲル電解質の例としては『表面科学』２１巻、第５号２８８〜２９３ページに記載の電解質が挙げられる。
【０１９４】
《対向電極》
本発明に用いられる対向電極について説明する。
【０１９５】
対向電極は、導電性を有するものであればよく、任意の導電性材料が用いられるが、Ｉ^３−イオン等の酸化や他のレドックスイオンの還元反応を充分な速さで行わせる触媒能を持ったものの使用が好ましい。このようなものとしては、白金電極、導電材料表面に白金めっきや白金蒸着を施したもの、ロジウム金属、ルテニウム金属、酸化ルテニウム、カーボン等が挙げられる。
【０１９６】
【実施例】
以下、実施例により本発明を説明するが、本発明はこれらに限定されない。
【０１９７】
実施例１
《光電変換素子１の作製》
下記に記載のようにして、図１に示すような光電変換素子を作製した。
【０１９８】
チタンテトライソプロポキシド（和光純薬社製一級）６２．５ｍｌを純水３７５ｍｌ中に室温下、激しく攪拌しながら１０分間で滴下し（白色の析出物が生成する）、次いで７０質量％硝酸水を２．６５ｍｌ加えて反応系を８０℃に加熱した後、８時間攪拌を続けた。さらに反応混合物の体積が約２００ｍｌになるまで減圧下に濃縮した後、純水を１２５ｍｌ、酸化チタン粉末（昭和タイタニウム社製スーパータイタニアＦ−６）１４０ｇを加えて酸化チタン懸濁液（約８００ｍｌ）を調製した。フッ素をドープした酸化スズをコートした透明導電性ガラス板上に酸化チタン懸濁液を塗布し、自然乾燥の後３００℃で６０分間焼成して、支持体上に膜状の酸化チタンを形成した。
【０１９９】
ついで、メタノール溶液２００ｍｌ中に、例示化合物Ｉ−１を５ｇ溶解した溶液を調製し、上記膜状酸化チタン（光電変換材料用半導体層）を支持体ごと浸し、さらにトリフルオロ酢酸１ｇを加えて２時間超音波照射した。反応後膜状酸化チタン（光電変換材料用半導体層）をクロロホルムで洗浄し真空乾燥して、感光層２（光電変換材料用半導体）を作製した。
【０２００】
対向電極４として、フッ素をドープした酸化スズをコートし、さらにその上に白金を担持した透明導電性ガラス板を用い、前記導電性支持体１と前記対向電極４との間に体積比が１：４であるアセトニトリル／炭酸エチレンの混合溶媒に、テトラプロピルアンモニウムアイオダイドと沃素とを、それぞれの濃度が０．４６モル／リットル、０．０６モル／リットルとなるように溶解したレドックス電解質を入れた電荷移動層３を作製して、光電変換素子１を作製した。
【０２０１】
《光電変換素子２〜５５の作製》：本発明
光電変換素子１の作製において、例示化合物Ｉ−１を表１、表２に記載の化合物に変更した以外は同様にして、光電変換素子２〜５５を得た。
【０２０２】
《光電変換素子Ｒ１及びＲ２の作製》：比較例
光電変換素子１の作製において、表１、表２に記載の比較化合物Ｒ１及びＲ２に変更した以外は同様にして、光電変換素子Ｒ１及びＲ２を得た。
【０２０３】
【化５８】

【０２０４】
《太陽電池ＳＣ−１〜ＳＣ−５５の作製》：本発明
光電変換素子１〜５５の側面を樹脂で封入した後、リード線を取り付けて、それぞれ太陽電池ＳＣ−１〜ＳＣ−５５を３ロットずつ作製した。
【０２０５】
《太陽電池ＳＣ−Ｒ１及びＲ２の作製》：比較例
上記の太陽電池ＳＣ−１の作製において、比較の光電変換素子Ｒ１及びＲ２を用いた以外は同様にして、太陽電池ＳＣ−Ｒ１及びＲ２を３ロットずつ作製した。
【０２０６】
《太陽電池の光電変換特性評価》
上記で得られた太陽電池ＳＣ−１〜ＳＣ−５５、及び太陽電池ＳＣ−Ｒ１、Ｒ２のそれぞれにソーラーシミュレーター（ＪＡＳＣＯ（日本分光）製、低エネルギー分光感度測定装置ＣＥＰ−２５）により１００ｍＷ／ｍ^２の強度の光を照射した時の短絡電流密度Ｊｓｃ（ｍＡ／ｃｍ^２）及び開放電圧値Ｖｏｃ（Ｖ）を測定し、その結果を表１、表２に示した。値は、同じ構成及び作製方法の太陽電池３つについての平均値とした。
【０２０７】
【表１】

【０２０８】
【表２】

【０２０９】
表１、表２より、比較に比べて、本発明の太陽電池は高い光電変換特性を示し、前記一般式（１）で表される化合物を用いることが有効であることが分かる。特に、色素のＱが一般式（Ｃｐ−１）、（Ｃｐ−２）、（Ｃｐ−３）、（Ｃｐ−４）、（Ｃｐ−６）、（Ｃｐ−１５）、一般式（４）または（５）で表される構造のものが優れていることが分かる。また、かつ、本発明の太陽電池ＳＣ−１〜ＳＣ−２０は、ソーラーシミュレーターによる１００ｍＷ／ｍ^２の光照射１００時間を経ても光電変換効率の低下が認められず、安定性に優れていることが明かになった。
【０２１０】
【発明の効果】
本発明により、高い光電変換効率と優れた安定性とを示す光電変換材料用半導体、光電変換素子及び太陽電池を提供することができた。
【図面の簡単な説明】
【図１】本発明の光電変換素子の構造の一例を示す部分断面図である。
【符号の説明】
１ 導電性支持体
２ 感光層
３ 電荷移動層
４ 対向電極[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor for a photoelectric conversion material, a photoelectric conversion element, and a solar cell.
[0002]
[Prior art]
A photoelectric conversion material is a material that converts light energy into electric energy using an electrochemical reaction between electrodes. When light is irradiated to the photoelectric conversion material, electrons are generated on one electrode side and move to the counter electrode. The electrons that have moved to the counter electrode move as ions in the electrolyte and return to one electrode.
[0003]
That is, the photoelectric conversion material is a material from which light energy can be continuously extracted as electric energy, and is used for, for example, a solar cell. Although there are several types of solar cells, most of the solar cell used in home-use power generation panels, desktop calculators, clocks, portable game machines, and the like are silicon solar cells.
[0004]
However, recently, dye-sensitized solar cells have attracted attention and have been studied for practical use. Dye-sensitized solar cells have been studied for a long time, and the basic structure thereof specifically includes a metal oxide semiconductor and a dye adsorbed thereon, an electrolyte solution, and a counter electrode.
[0005]
In the conventional dye-sensitized solar cell as described above, a photoelectric conversion material in which a spectral sensitizing dye having absorption in a visible light region is adsorbed on a semiconductor surface is used. For example, a solar cell having a spectral sensitizing dye layer of a transition metal complex or the like on the surface of a metal oxide semiconductor (for example, see Patent Document 1), or a titanium oxide semiconductor doped with metal ions A solar cell having a layer of a spectral sensitizing dye such as a transition metal complex on the surface of the layer is described (for example, see Patent Document 2).
[0006]
On the other hand, as an oxide semiconductor electrode having photoelectric conversion ability, a semiconductor single crystal electrode has been used in the early days. The type is titanium oxide (TiO 2). ₂ ), Zinc oxide (ZnO), tin oxide (SnO) ₂ ).
[0007]
However, the single crystal electrode has the disadvantage that the efficiency of the single crystal electrode is very low due to the small amount of dye adsorbed and the cost is high. Thus, a high surface area semiconductor electrode having a large number of pores formed by sintering fine particles has been devised.
[0008]
For example, Tsubomura et al. Reported that a porous zinc oxide electrode having an organic dye adsorbed thereon has extremely high performance (for example, see Non-Patent Document 1).
[0009]
Since then, dyes have been improved, and Graetzel et al. Now adsorb ruthenium complex-based dyes on porous titanium oxide electrodes, so that they now have performance comparable to silicon solar cells (for example, , Non-Patent Document 2).
[0010]
However, for practical use to replace silicon solar cells, higher energy conversion efficiency, higher short-circuit current, open-circuit voltage, and form factor are required. The reported substances are ZnO, TiO ₂ , Zirconium oxide (ZrO ₂ ), Niobium oxide (Nb ₂ O ₅ ) Etc. are being developed.
[0011]
In addition, since the dye-sensitized wet solar cell has a very low manufacturing cost compared to the silicon solar cell, there is a possibility that the silicon solar cell used in the above-mentioned various products may be replaced in the future. In that case, the characteristics of the solar cell corresponding to each product become important. Among the characteristics of solar cells, there are various
1. Short-circuit current
2. Open circuit voltage
3. Form factor
4. Energy conversion efficiency
5. Optical absorption spectrum
Are important, but especially 4. Energy conversion efficiency is the biggest issue for solar cells, and its improvement has been strongly desired. As one of the technical issues that affect the efficiency, a sensitizing dye having the ability to efficiently transfer photoexcited electrons to a semiconductor is required. Among the various dyes studied so far, the ruthenium complex dye is known to have relatively excellent properties, but the dye is expensive, and ruthenium, which is the central metal of the complex, is a rare element. Therefore, there is a concern about stable supply in the future, and therefore, an organic dye that can be supplied stably at a lower cost is more preferable. From such demands, many organic dyes have been studied so far, but the photoelectric conversion efficiency is not yet sufficient, and an organic dye capable of forming a photoelectric conversion element with higher conversion efficiency has been long-awaited.
[0012]
Various dyes have been studied in addition to the ruthenium complex dye, but well-known dyes include merocyanine dyes, xanthene dyes, coumarin dyes, acridine dyes, and phenylmethane dyes. Above all, there are many patents for merocyanine dyes. For example, the dye described in JP-A-11-167937 is an odd-number methine dye, which is characterized in that the molecule is cationic and has a counter salt. Japanese Patent Application Laid-Open No. H11-214730 describes a compound having a methine number of 3 or more, such as a trimethine dye. JP-A-11-214731 describes an even-number methine dye. On the other hand, a photoelectric conversion element using an azobenzene derivative dye is also described in JP-A-5-206489, JP-A-2002-376885, JP-A-2003-7358, etc., and any dye has satisfactory performance. Therefore, further development of highly efficient dyes is desired.
[0013]
[Patent Document 1]
JP-A-1-220380
[0014]
[Patent Document 2]
Japanese Unexamined Patent Publication No. Hei 5-504023
[0015]
[Non-patent document 1]
Nature, 261 (1976) p402
[0016]
[Non-patent document 2]
J. Am. Chem. Soc. , 115 (1993) 6382.
[0017]
[Problems to be solved by the invention]
An object of the present invention is to provide a semiconductor for a photoelectric conversion material, a photoelectric conversion element, and a solar cell that exhibit high photoelectric conversion efficiency and excellent stability.
[0018]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following constitutions.
[0019]
1. A semiconductor for a photoelectric conversion material, comprising a dye represented by the general formula (1).
[0020]
2. Said B ₁ And B ₂ Is -N =, the semiconductor for a photoelectric conversion material according to the above 1, wherein
[0021]
3. 3. The semiconductor for a photoelectric conversion material according to 1 or 2, wherein A is a 6-membered aromatic group.
[0022]
4. The Q is represented by the general formulas (Cp-1), (Cp-2), (Cp-3), (Cp-4), (Cp-6), and (Cp-15). 4. The semiconductor for a photoelectric conversion material according to any one of 1 to 3 above.
[0023]
5. In the general formulas (Cp-1), (Cp-2) and (Cp-3), R ₆₄ Is represented by the general formula (6).
[0024]
6. The semiconductor for a photoelectric conversion material according to any one of the above items 1 to 5, wherein the semiconductor for a photoelectric conversion material is a metal oxide or a metal sulfide semiconductor.
[0025]
7. 6. A photoelectric conversion element, wherein a layer containing the semiconductor for a photoelectric conversion material according to any one of 1 to 5 is provided on a conductive support.
[0026]
8. A solar cell comprising the photoelectric conversion element, the charge transfer layer, and the counter electrode according to the above item 7.
[0027]
Hereinafter, the present invention will be described in detail.
The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the present invention provides a semiconductor for a photoelectric conversion material sensitized with a compound having a specific structure represented by the general formula (1). , Ie, a semiconductor for a photoelectric conversion material exhibiting high photoelectric conversion efficiency and excellent stability was successfully obtained.
[0028]
《Semiconductor for photoelectric conversion materials》
Examples of the semiconductor used for the semiconductor for a photoelectric conversion material of the present invention include a simple substance such as silicon and germanium, and a compound having an element belonging to Group 3 to Group 5 or Group 13 to 15 of the periodic table (also referred to as the periodic table of elements). Metal chalcogenides (eg, oxides, sulfides, selenides, etc.), metal nitrides and the like can be used.
[0029]
Preferred metal chalcogenides include titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, or tantalum oxide, cadmium, zinc, lead, silver, antimony or Examples include sulfide of bismuth, selenide of cadmium or lead, and telluride of cadmium. Other compound semiconductors include phosphides such as zinc, gallium, indium and cadmium, selenides of gallium-arsenic or copper-indium, sulfides of copper-indium, and nitrides of titanium.
[0030]
Specific examples of the semiconductor according to the semiconductor for a photoelectric conversion material of the present invention include TiO. ₂ , SnO ₂ , Fe ₂ O ₃ , WO ₃ , ZnO, Nb ₂ O ₅ , CdS, ZnS, PbS, Bi ₂ S ₃ , CdSe, CdTe, GaP, InP, GaAs, CuInS ₂ , CuInSe ₂ , Ti ₃ N ₄ And the like, preferably TiO 2 ₂ , ZnO, SnO ₂ , Fe ₂ O ₃ , WO ₃ , Nb ₂ O ₅ , CdS and PbS, more preferably TiO ₂ Or Nb ₂ O ₅ However, among them, TiO is preferable. ₂ It is.
[0031]
As the semiconductor used for the semiconductor for a photoelectric conversion material of the present invention, a plurality of the above-described semiconductors may be used in combination. For example, several kinds of the above-described metal oxides or metal sulfides can be used in combination, and 20% by mass of titanium nitride (Ti ₃ N ₄ ) May be used as a mixture. Also, J.I. Chem. Soc. Chem. Commun. , 15 (1999). At this time, when a component other than the metal oxide or the metal sulfide is added as the semiconductor, the mass ratio of the additional component to the metal oxide or the metal sulfide semiconductor is preferably 30% by mass or less.
[0032]
By subjecting the above-mentioned semiconductor for a photoelectric conversion material to a sensitization treatment with the compound represented by the general formula (1), the object of the present invention is to provide a semiconductor for a photoelectric conversion material that exhibits high photoelectric conversion efficiency and excellent stability. Can be obtained.
[0033]
Hereinafter, the compound represented by Formula (1) will be described.
<< Compound represented by the general formula (1) >>
A represents a 5- to 6-membered aromatic or heterocyclic group; ₁ And B ₂ Is -CR ₁ = Or -N =, at least one of which represents -N =, R ₁ Represents a hydrogen atom or a substituent, Q is represented by any of formulas (2) to (5), and has at least one carboxyl group in the molecule.
[0034]
The substituent is not particularly limited as long as it can be substituted. For example, an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a dodecyl group) , Tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), bicycloalkyl group (eg, bicyclo [1,2,2] heptane-2-yl group, bicyclo [2 , 2,2] octan-3-yl) group), alkenyl group (for example, vinyl group, allyl group, prenyl group, octenyl group and the like), cycloalkenyl group (for example, 2-cyclopenten-1-yl group) , 2-cyclohexen-1-yl group, etc.), bicycloalkenyl group (for example, bicyclo [2,2,1] hept- -En-1-yl group, bicyclo [2,2,2] oct-2-en-4-yl group, etc.), alkynyl group (eg, propargyl group, ethynyl group, trimethylsilylethynyl group, etc.), aryl group (eg, Phenyl group, naphthyl group, p-tolyl group, m-chlorophenyl group, o-hexadecanoylaminophenyl group, etc., heterocyclic group (for example, pyridyl group, thiazolyl group, oxazolyl group, imidazolyl group, furyl group, pyrrolyl) Group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, sulfolanyl group, piperidinyl group, pyrazolyl group, tetrazolyl group, etc.), heterocyclic oxy group (for example, 1-phenyltetrazole-5-oxy group, 2-tetrahydropyranyl) Oxy group, pyridyloxy group, thiazolyloxy group, oxazolyloxy group, A midazolyloxy group, a halogen atom (eg, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom, etc.), an alkoxyl group (eg, a methoxy group, an ethoxy group, a propyloxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group) Group, octyloxy group, dodecyloxy group, etc.), cycloalkoxyl group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, 2-methylphenoxy group, 4-tert. -Butylphenoxy group, 3-nitrophenoxy group, 2-tetradecanoylaminophenoxy group, etc.), alkylthio group (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), Cyclo Alkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), heterocyclic thio group (eg, pyridylthio group, thiazolylthio group, oxazolylthio group, imidazolylthio group, furylthio group , A pyrrolylthio group, etc.), an alkoxycarbonyl group (eg, a methyloxycarbonyl group, an ethyloxycarbonyl group, a butyloxycarbonyl group, an octyloxycarbonyl group, a dodecyloxycarbonyl group, etc.), an aryloxycarbonyl group (eg, a phenyloxycarbonyl group) , Naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylamido) Sulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group and the like, ureido group (for example, methylureido group, ethylureido group, pentyl) Ureido group, cyclohexylureide group, octylureide group, dodecylureide group, phenylureide group, naphthylureide group, 2-pyridylaminoureide group, etc., acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group) , Cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylca Carbonyl group, etc.), acyloxy group (for example, formyloxy group, acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy) Group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), acylamino group (for example, acetylamino group, benzoylamino group, formylamino group, pivaloylamino group, lauroylamino group, 3,4,5-tri-n-octyloxy) Phenylcarbonylamino group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, Xylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc., carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylamino Carbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group Etc.), alkylsulfinyl group or arylsulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butyls Finyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc., alkylsulfonyl group or arylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group) Butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc., amino group (for example, amino group, methylamino group, ethylamino group) Dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, N-methylanilino group, diphenylamido Group, naphthylamino group, 2-pyridylamino group, etc.), silyloxy group (eg, trimethylsilyloxy group, tert-butyldimethylsilyloxy group, etc.), aminocarbonyloxy group (eg, N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N, N-di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy group, etc., alkoxycarbonyloxy group (for example, methoxycarbonyloxy group, ethoxy Carbonyloxy group, tert-butoxycarbonyloxy group, n-octylcarbonyloxy group, etc.), aryloxycarbonyloxy group (for example, phenoxycarbonyloxy group, p-methoxyphenoxycarbonyloxy group, p-n-f Xadecyloxyphenoxycarbonyloxy group, etc., alkoxycarbonylamino group (for example, methoxycarbonylamino group, ethoxycarbonylamino group, tert-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxycarbonylamino group Etc.), an aryloxycarbonylamino group (for example, a phenoxycarbonylamino group, a p-chlorophenoxycarbonylamino group, a mn-octyloxyphenoxycarbonylamino group, etc.), a sulfamoylamino group (for example, a sulfamoylamino group) , N, N-dimethylaminosulfonylamino group, Nn-octylaminosulfonylamino group, etc.), mercapto group, arylazo group (for example, phenylazo group, naphthylazo group, p-chlorophenyl) Azo group, etc.), heterocyclic azo group (for example, pyridylazo group, thiazolylazo group, oxazolylazo group, imidazolylazo group, furylazo group, pyrrolylazo group, 5-ethylthio-1,3,4-thiadiazol-2-ylazo group), imino Group (for example, N-succinimido-1-yl group, N-phthalimido-1-yl group, etc.), phosphino group (for example, dimethylphosphino group, diphenylphosphino group, methylphenoxyphosphino group, etc.), phosphinyl group ( For example, phosphinyl group, dioctyloxyphosphinyl group, diethoxyphosphinyl group, etc.), phosphinyloxy group (eg, diphenoxyphosphinyloxy group, dioctyloxyphosphinyloxy group, etc.), phosphinyl Amino group (for example, dimethoxyphosphinylamino group, dimethyl Mino phosphinyl amino group, etc.), a silyl group (e.g., trimethylsilyl group, tert- butyldimethylsilyl group, phenyldimethylsilyl group, etc.), a cyano group, a nitro group, a hydroxyl group, a sulfo group, a carboxyl group.
[0035]
R ₁ Preferred are a hydrogen atom, an alkyl group, an aryl group, and a heterocyclic group, and more preferred are a hydrogen atom and an alkyl group.
[0036]
A in the general formula (1) represents a 5- to 6-membered aromatic or heterocyclic group. Examples of the 5- or 6-membered aromatic carbocycle include a benzene ring, a naphthalene ring, an indene ring, a tetralin ring, an anthracene ring, and a phenanthrene ring. As the 5- or 6-membered heterocyclic ring, an aromatic heterocyclic ring (for example, a furan ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, a 1,2,3-oxadiazole ring, 2,3-triazole ring, 1,2,4-triazole ring, 1,3,4-thiadiazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, s-triazine ring, benzofuran ring, indole ring, benzothiophene Ring, benzimidazole ring, benzothiazole ring, purine ring, quinoline ring and isoquinoline ring) and heterocycle (pyran ring, chromene ring, xanthene ring, carbazole ring, β-carboline ring, isochroman ring, chroman ring, pyrrolidine ring, Pyrroline ring, imidazolidine ring, imidazoline ring, pyrazolidine ring, pyrazoline ring, piperidi Ring, piperazine ring, indoline ring, isoindoline ring, quinuclidine ring, morpholine ring, etc.).
[0037]
The above-mentioned aromatic carbocycle and heterocycle may be a single ring or a condensed ring, and may further have a substituent.
[0038]
A is preferably a 6-membered benzene ring or naphthalene ring as an aromatic carbocycle, or a furan ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyridine ring, a pyridazine ring, or a pyrimidine as a heterocyclic ring. And a pyrazine ring, and more preferably a benzene ring, a naphthalene ring, a furan ring, a pyrrole ring, an imidazole ring, an oxazole ring, a thiazole ring, and a pyridine ring.
[0039]
Further, in addition to the compound represented by the general formula (1), it includes ions and salts derived from the compound. For example, when the compound represented by the general formula (1) has a sulfo group in the molecular structure, in addition to the compound, an anion generated by dissociation of the sulfo group and the anion and counter cation And the salts formed with
[0040]
Such salts may be salts formed with metal ions such as sodium salt, potassium salt, magnesium salt and calcium salt, and organic bases such as pyridine, piperidine, triethylamine, aniline and diazabicycloundecene. May be formed. Similarly, in the case of a compound having a basic group in the molecule, a cation generated by protonation of the compound, and hydrochloride, sulfate, acetate, methyl sulfonate, p-toluene sulfonate, and the like, An inner salt formed with an acid is also included.
[0041]
Next, general formulas (2) to (5) represented by Q will be described.
In the general formulas (2) and (3), B ₃ Is CR ₃ Or a nitrogen atom, R ₂ And R ₃ Represents a hydrogen atom or a substituent, Z represents an atom group necessary for forming a 5- or 6-membered ring, may have a substituent, is bonded by *, and has at least one carboxyl in the molecule. Having a group. The substituent herein has the same meaning as the substituent of the general formula (1).
[0042]
R ₂ Preferred examples include a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carboxyl group, an alkoxy group and an amino group, and more preferred are an alkyl group, an aryl group, an alkoxy group and a carboxyl group.
[0043]
R ₃ Preferred are a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carboxyl group, an alkoxycarbonyl group, a cyano group, and a halogen atom, and more preferably a hydrogen atom, an alkyl group, an aryl group, a carboxyl group, and a cyano group. Group.
[0044]
The 5- or 6-membered ring represented by Z forms a triazole ring, an imidazole ring, a pyrazole ring, a pyrimidine-one ring, a triazine-one ring, etc. together with a carbon atom or a nitrogen atom of the general formulas (2) and (3). It is preferable to use a compound that forms a nitrogen-containing ring (for example, a pyrrole ring, a pyridine ring, a pyrimidine ring, a pyrazine ring, and the like).
[0045]
In the general formula (4), R ₄ And R ₅ Represents a hydrogen atom or a substituent; ₈ Represents a hydrogen atom, an alkyl group, or an acyl group, is bonded by *, and has at least one carboxyl group in the molecule. The substituent herein has the same meaning as the substituent of the general formula (1).
[0046]
R ₄ Preferred examples include a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carboxyl group, an alkoxy group and an amino group, and more preferred are an alkyl group, an aryl group, an alkoxy group and a carboxyl group.
[0047]
R ₅ Preferred are a hydrogen atom, an alkyl group, an aryl group, and a heterocyclic group, and more preferred are an alkyl group and an aryl group.
[0048]
In the general formula (5), B ₄ Is CR ₇ Or a nitrogen atom, R ₄ , R ₆ And R ₇ Represents a hydrogen atom or a substituent; ₈ Represents a hydrogen atom, an alkyl group, or an acyl group, is bonded by *, and has at least one carboxyl group in the molecule. The substituent herein has the same meaning as the substituent of the general formula (1), but more specifically, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, an alkyl or arylsulfonylamino group, an amino group, an alkylthio group , An arylthio group, an alkoxy group, an aryloxy group, an ureido group, an alkoxycarbonylamino group, an acyl group, a cyano group, a carboxyl group, an alkoxycarbonyl group or a carbamoyl group.
[0049]
R ₄ And R ₆ Preferred examples include a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carboxyl group, an alkoxy group and an amino group, and more preferred are an alkyl group, an aryl group, an alkoxy group and a carboxyl group.
[0050]
R ₇ Preferably, a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carboxyl group, an alkoxycarbonyl group, a cyano group, a halogen atom, and more preferably, a hydrogen atom, an alkyl group, an aryl group, a carboxyl group, It is a cyano group.
[0051]
In general formulas (2) and (3) represented by Q, atomic groups (partial structures) represented by the following general formulas (Cp-1) to (Cp-18) are preferably used.
[0052]
Here, the atomic groups represented by the general formulas (Cp-1) to (Cp-18) are bonded to portions other than Q in the general formula (1) at the positions indicated by *. Further, Q according to the present invention is not limited by these.
[0053]
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[0054]
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[0055]
Hereinafter, the atomic groups represented by the general formulas (Cp-1) to (Cp-18) will be described in detail.
[0056]
<< Atom group represented by general formulas (Cp-1) and (Cp-2) >>
In the general formulas (Cp-1) and (Cp-2), R ₆₂ Represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, or an acyl group; ₆₃ , R ₆₄ Represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an amino group, an alkylamino group, an alkylthio group, an arylthio group, an alkoxyl group, and an aryloxy group, respectively. Represents a group, a ureido group, an alkoxycarbonylamino group, a carbamoyl group, a carboxyl group or an alkoxycarbonyl group.
[0057]
Where R ₆₂ The group represented by preferably includes a hydrogen atom, an alkyl group, and an acyl group.
[0058]
Where R ₆₃ Examples of the group represented by preferably include an alkyl group, an aryl group, a carboxyl group, an alkoxyl group, and a carbamoyl group, and more preferably a methyl group, a tert-butyl group, and a carboxyl group.
[0059]
Where R ₆₄ The group represented by is preferably an alkyl group, an alkenyl group, or an aryl group.
[0060]
<< Atom group represented by general formulas (Cp-3) and (Cp-4) >>
In the general formulas (Cp-3) and (Cp-4), R ₆₂ , R ₆₃ And R ₆₄ Represents R represented by the general formulas (Cp-1) and (Cp-2). ₆₂ , R ₆₃ And R ₆₄ Is synonymous with
[0061]
R ₆₅ And R ₆₇ Is a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an amino group, an alkylthio group, an arylthio group, an alkoxyl group, an aryloxy group, a ureido group, an alkoxy group, respectively. Represents a carbonylamino group, an acyl group, a carboxyl group, an alkoxycarbonyl group or a carbamoyl group.
[0062]
Where R ₆₅ The group represented by preferably includes an alkyl group, an aryl group, an alkoxyl group, an aryloxy group and the like. ₆₃ , R ₆₄ , R ₆₇ Preferred examples of the groups include a hydrogen atom, an alkyl group, an aryl group, a carboxyl group, an alkoxycarbonyl group, and a carbamoyl group.
[0063]
<< Atom group represented by general formula (Cp-5) >>
In the general formula (Cp-5), R ₆₈ And R ₆₉ Are hydrogen, alkyl, aryl, heterocyclic, acylamino, alkylsulfonyl, arylsulfonylamino, amino, alkylthio, arylthio, alkoxyl, aryloxy, ureido, alkoxycarbonylamino, respectively. A carboxyl group, an acyl group, an alkoxycarbonyl group or a carbamoyl group.
[0064]
In the general formula (Cp-5), R ₆₂ Represents R represented by the general formulas (Cp-1) and (Cp-2). ₆₂ Is synonymous with
[0065]
Where R ₆₈ , R ₆₉ The group represented by preferably includes a hydrogen atom, an alkyl group, an aryl group, a carboxyl group, and the like.
[0066]
<< Atomic groups represented by general formulas (Cp-6) to (Cp-10) >>
In the general formulas (Cp-6) to (Cp-10), R ₈₇ , R ₈₈ Represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group, a cyano group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, or a nitro group, respectively. R ₈₉ , R ₉₀ Each represents a hydrogen atom, a carboxyl group, an alkyl group, an aryl group, or a heterocyclic group; ₆₂ Represents R represented by the general formulas (Cp-1) and (Cp-2). ₆ Is synonymous with
[0067]
Where R ₈₇ The group represented by is preferably a carbamoyl group, an alkoxycarbonyl group, a carboxyl group, a cyano group, and the like, and more preferably a carboxyl group and a cyano group. R ₈₈ The group represented by is a carbamoyl group, a carboxyl group, an alkoxycarbonyl group, a cyano group, an alkylsulfonyl group, an arylsulfonyl group and the like, and more preferably an alkoxycarbonyl group and a carboxyl group. R ₈₉ , R ₉₀ The groups represented by each are preferably an alkyl group, an aryl group, and the like, and more preferably an aryl group.
[0068]
<< Atomic groups represented by general formulas (Cp-11) to (Cp-18) >>
In the general formulas (Cp-11) to (Cp-18), R ₉₁ , R ₉₂ Represents an alkyl group, an aryl group, a heterocyclic group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group, a cyano group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group or a nitro group, ₉₃ , R ₉₄ , R ₉₅ Are a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, a ureido group, an alkoxycarbonylamino group, an alkyl or arylsulfonylamino group, a halogen atom, a carboxyl group, an amino group, an alkylthio group, an arylthio group, and an alkoxyl, respectively. A group or an aryloxy group, ₆₂ Represents R represented by the general formulas (Cp-1) and (Cp-2). ₆ Is synonymous with
[0069]
Where R ₉₁ The group represented by is preferably an aryl group, a heterocyclic group, a carbamoyl group, an alkoxycarbonyl group, a carboxyl group, a cyano group, and the like. ₉₂ The group represented by is preferably a carbamoyl group, an alkoxycarbonyl group, a carboxyl group, a cyano group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, and the like. ₉₃ , R ₉₄ , R ₉₅ The groups represented by preferably each include a hydrogen atom, an alkyl group, an acylamino group, a halogen atom, a carboxyl group, an amino group, an alkylthio group, an arylthio group, and the like.
[0070]
Further, Q is preferably represented by the following general formulas a to d.
[0071]
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[0072]
In the general formulas a to d, R ₄ 'And R ₅ 'Represents a hydrogen atom or a substituent; ₂ Represents an atomic group necessary for forming a 5- or 6-membered ring, and may have a substituent, may be bonded by a substituent to form a condensed ring, and * is bonded to a moiety other than Q. I do. At least one has a carboxyl group. R ₄ 'And R ₅ The substituent 'is the same as the substituent described above. R ₆ 'Is a hydrogen atom, an alkyl group or an acyl group.
[0073]
Z ₂ More specifically, for example, in the case of the general formula a, compounds represented by the following general formulas a-1 to a-9 and the like can be mentioned.
[0074]
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[0075]
The general formulas a-1 to a-3 and a-6 to a-9 are the same compounds as the general formulas (Cp-1) to (Cp-3) and (Cp-15) to (Cp-18). And R in general formulas a-4 and a-5 ₄ ', R ₅ ', R ₆ 'Is synonymous with them.
[0076]
R ₄ '~ R ₇ 'Each represents a hydrogen atom or a substituent, and the structures of a-1, a-2, a-3, a-6 and a-7 are preferred, and more preferably a-1, a-3 and a-6 is there.
[0077]
In formulas b to d, compounds having the same structure can be mentioned. For example, general formula b is general formulas (Cp-8), (Cp-10), (Cp-12) and (Cp-14), while general formula c is general formulas (Cp-6) and (Cp-7). , (Cp-9), (Cp-11) and (Cp-13), and the general formula d includes general formulas (Cp-4) to (Cp-5), but is not limited thereto. .
[0078]
Preferred structures in the general formulas (Cp-1) to (Cp-18) include (Cp-1), (Cp-2), (Cp-3), (Cp-4), (Cp-6), and ( (Cp-7), (Cp-8), (Cp-11), (Cp-12), (Cp-15) and (Cp-16), and more preferably (Cp-1) and (Cp-16). -2), (Cp-3), (Cp-4), (Cp-6) and (Cp-15).
[0079]
Next, the general formula (6) will be described. R64 in the general formulas (Cp-1) to (Cp-3) is preferably represented by the general formula (6).
[0080]
In the general formula (6), R ₉ Or R ₁₀ Represents a hydrogen atom or a substituent, n represents an integer of 0 to 3, and when n is 1 or more, R ₉ And R ₁₀ May combine to form a 5- to 6-membered ring. The substituent herein has the same meaning as the substituent of the general formula (1).
[0081]
R ₉ And R ₁₀ Specific examples of the substituent include an alkyl group, a cycloalkyl group, a halogen atom, a carboxyl group, and an alkoxycarbonyl group. ₉ And R ₁₀ Is more preferably a hydrogen atom or an alkyl group. n is preferably 0 to 2, and more preferably 0 to 1.
[0082]
Hereinafter, specific examples of the compound represented by Formula (1) according to the present invention are shown, but the present invention is not limited thereto.
[0083]
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[0084]
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[0085]
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[0086]
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[0087]
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[0088]
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[0089]
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[0090]
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[0091]
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[0092]
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[0093]
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[0094]
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[0095]
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[0096]
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[0097]
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[0098]
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[0099]
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[0100]
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[0101]
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[0102]
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[0103]
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[0104]
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[0105]
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[0106]
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[0107]
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[0108]
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[0109]
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[0110]
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[0111]
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[0112]
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[0113]
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[0114]
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[0115]
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[0116]
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[0117]
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[0118]
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[0119]
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[0120]
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[0121]
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[0122]
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[0123]
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[0124]
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[0125]
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[0126]
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[0127]
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[0128]
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[0129]
The compounds represented by the general formula (1) according to the present invention include, for example, JP-A-5-177958, JP-A-10-265690, JP-A-11-189728, JP-A-9-220861, JP-A-2001-279123 and the like. Can be synthesized with reference to a conventionally known method described in (1).
[0130]
Specific examples of the synthesis method are shown below, but other compounds can be synthesized in the same manner, and the synthesis method is not limited thereto.
[0131]
(Synthesis of Exemplified Compound I-1)
According to the synthesis route described below, Exemplified Compound I-1 was synthesized.
[0132]
(1) Synthesis route
[0133]
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[0134]
(2) Synthesis of Exemplified Compound I-1
60 ml of ethanol and 3.92 g of Intermediate 2 are added to 5.24 g of Intermediate 1, and the mixture is heated and refluxed for 3 hours. After the reaction, cool. The precipitated crystals were filtered and washed with ethyl acetate to obtain 7.18 g of Exemplified Compound I-1. It was identified by MASS, H-NMR, and IR spectrum, and it was confirmed that it was a target.
[0135]
(Synthesis of Exemplified Compound III-1)
According to the synthesis route described below, Exemplified Compound III-1 was synthesized.
[0136]
(1) Synthesis route
[0137]
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[0138]
(2) Synthesis of Exemplified Compound III-1
50 ml of methanol and 7 ml of triethylamine are added to 2.34 g of the intermediate 3, and the mixture is cooled to 5 ° C. A separately prepared aqueous suspension of 2.48 g of Intermediate 4 was dropped at 10 ° C. or lower over 30 minutes to react. After completion of the reaction, the mixture was brought to room temperature, and the precipitated crystals were filtered and recrystallized from acetonitrile to obtain 2.63 g of Exemplified Compound III-1. It was identified by MASS, H-NMR, and IR spectrum, and it was confirmed that it was a target.
[0139]
《Sensitization of semiconductors for photoelectric conversion materials》
The semiconductor for a photoelectric conversion material of the present invention sensitizes by containing the compound represented by the general formula (1), and can exhibit the effects described in the present invention. Here, the term “comprising a compound” refers to various modes such as adsorption to a semiconductor surface, and when the semiconductor has a porous structure such as a porous structure, the compound enters the porous structure of the semiconductor. 1 m of semiconductor layer (may be a semiconductor) ² The total content of the compound represented by the general formula (1) is preferably in the range of 0.01 to 100 mmol, more preferably 0.1 to 50 mmol, particularly preferably 0.5 to 20 mmol. is there.
[0140]
When sensitization treatment is performed using the compound represented by the general formula (1) according to the present invention, the compound may be used alone or in combination of two or more, according to the general formula according to the present invention. (The compound represented by 1 and another compound (for example, US Pat. Nos. 4,684,537, 4,927,721, 5,084,365, and 5,350,644) No. 5,463,057 and 5,525,440, and compounds described in JP-A-7-249790, JP-A-2000-150007 and the like. You can also.
[0141]
In particular, when the application of the semiconductor for a photoelectric conversion material of the present invention is a solar cell to be described later, two types having different absorption wavelengths are used so that the wavelength region of the photoelectric conversion is made as wide as possible and sunlight can be used effectively. It is preferable to use a mixture of the above dyes.
[0142]
In order to include the compound represented by the general formula (1) in a semiconductor, a method of dissolving the compound in an appropriate solvent (such as ethanol) and immersing a well-dried semiconductor in the solution for a long time is generally used. It is a target.
[0143]
When a plurality of compounds represented by the general formula (1) are used in combination, or when a semiconductor for a photoelectric conversion material is used in combination with another sensitizing dye compound, a mixed solution of each compound is prepared. It may be used, or a solution may be prepared for each compound and immersed in each solution in order. When preparing a separate solution for each compound and immersing it in each solution in order, the effects described in the present invention are obtained regardless of the order in which the semiconductor or the compound or the sensitizing dye is included. be able to. Alternatively, it may be produced by mixing semiconductor fine particles adsorbing the compound alone.
[0144]
The adsorption treatment may be performed when the semiconductor is in the form of particles, or may be performed after forming a film on the support. The solution in which the compound used for the adsorption treatment is dissolved may be used at normal temperature, or may be used by heating at a temperature within a range where the compound does not decompose and the solution does not boil. In addition, the adsorption of the compound may be performed after the application of the semiconductor fine particles (after the formation of the photosensitive layer) as in the production of a photoelectric conversion element described later. Alternatively, the compound may be adsorbed by simultaneously applying the semiconductor fine particles and the compound of the present invention. Unadsorbed compounds can be removed by washing.
[0145]
Further, in the sensitization treatment of the semiconductor for a photoelectric conversion material of the present invention, the semiconductor is subjected to the sensitization treatment by containing the compound represented by the general formula (1). This will be specifically described in a photoelectric conversion element described later.
[0146]
Further, in the case of a semiconductor for a photoelectric conversion material having a semiconductor thin film having a high porosity, the compound or the sensitizer is used before water is adsorbed on the semiconductor thin film due to moisture, water vapor, or the like, as well as in the void inside the semiconductor thin film. It is preferable to complete the adsorption treatment of the dye compound or the like (sensitization treatment of the semiconductor for a photoelectric conversion material).
[0147]
The semiconductor for a photoelectric conversion material of the present invention may be subjected to a surface treatment using an organic base. Examples of the organic base include diarylamine, triarylamine, pyridine, 4-t-butylpyridine, polyvinylpyridine, quinoline, piperidine, amidine and the like, among which pyridine, 4-t-butylpyridine, polyvinylpyridine preferable.
[0148]
When the organic base is liquid, the solution is dissolved in an organic solvent if it is solid, and a solution prepared in an organic solvent is prepared, and the semiconductor for a photoelectric conversion material of the present invention is immersed in a liquid amine or an amine solution to perform a surface treatment. .
[0149]
As the dye that can be used in combination with the compound represented by the general formula (1) according to the present invention, any dye that can spectrally sensitize the semiconductor according to the present invention can be used. it can. In order to widen the wavelength range of photoelectric conversion as much as possible and to increase the conversion efficiency, it is preferable to mix two or more dyes. The dyes to be mixed and their proportions can be selected so as to match the wavelength range and intensity distribution of the target light source.
[0150]
Among the dyes according to the present invention, metal complex dyes, phthalocyanine dyes, porphyrin dyes, and polymethine dyes are preferably used from a comprehensive viewpoint such as photoelectron transfer reaction activity, light durability, and photochemical stability.
[0151]
Among the metal complex dyes, JP-A-2001-223037, JP-A-2001-226607, U.S. Pat. Nos. 4,927,721, 4,684,537, 5,084,365, and Nos. 5,350,644, 5,463,057, 5,525,440, JP-A-7-249750, JP-T-10-504512, and World Patent 989/50393. Ruthenium complex dyes are preferably used.
[0152]
As porphyrin-based dyes and phthalocyanine-based dyes, the dyes described in JP-A-2001-223037 are preferable.
[0153]
Examples of the polymethine dyes include conventionally known methine dyes, JP-A-11-35836, JP-A-11-158395, JP-A-11-163378, JP-A-11-214730, JP-A-11-214731, and JP-A-10-93118. JP-A-11-273754, JP-A-2000-106224, JP-A-2000-357809, JP-A-2001-52766, European Patent Nos. 892,411 and 911,841 and the like.
[0154]
<< Method of manufacturing semiconductor for photoelectric conversion material >>
A method for manufacturing a semiconductor for a photoelectric conversion material of the present invention will be described.
[0155]
One embodiment of the semiconductor for a photoelectric conversion material of the present invention includes a method of forming the above-described semiconductor for a photoelectric conversion material on a conductive support by firing.
[0156]
In the case where the semiconductor for a photoelectric conversion material of the present invention is produced by firing, the sensitization (adsorption, penetration into porous material, etc.) of the semiconductor using the above compound or sensitizing dye is performed after firing. Is preferred. It is particularly preferable to perform the compound adsorption treatment quickly after the firing and before water is adsorbed on the semiconductor.
[0157]
When the semiconductor for a photoelectric conversion material of the present invention is in the form of particles, the semiconductor for a photoelectric conversion material is preferably applied or sprayed on a conductive support to produce a semiconductor electrode. Further, when the semiconductor for a photoelectric conversion material of the present invention is in the form of a film and is not held on a conductive support, the semiconductor for a photoelectric conversion material is bonded to the conductive support to form a semiconductor electrode. It is preferable to make them.
[0158]
Hereinafter, the manufacturing process of the semiconductor for a photoelectric conversion material of the present invention will be specifically described.
<< Preparation of coating solution containing semiconductor fine powder >>
First, a coating solution containing fine semiconductor powder is prepared. This semiconductor fine powder preferably has a smaller primary particle diameter, and preferably has a primary particle diameter of 1 to 5000 nm, more preferably 2 to 50 nm. The coating liquid containing the semiconductor fine powder can be prepared by dispersing the semiconductor fine powder in a solvent. The semiconductor fine powder dispersed in the solvent is dispersed in the form of primary particles. The solvent is not particularly limited as long as it can disperse the semiconductor fine powder.
[0159]
The solvent includes water, an organic solvent, and a mixture of water and an organic solvent. Examples of the organic solvent include alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone, acetone and acetylacetone, and hydrocarbons such as hexane and cyclohexane. If necessary, a surfactant or a viscosity modifier (polyhydric alcohol such as polyethylene glycol) can be added to the coating solution. The concentration of the semiconductor fine powder in the solvent is preferably from 0.1 to 70% by mass, more preferably from 0.1 to 30% by mass.
[0160]
<< Application of coating solution containing semiconductor fine powder and baking treatment of formed semiconductor layer >>
The semiconductor fine powder-containing coating solution obtained as described above is applied or sprayed on a conductive support, dried and the like, and then fired in air or an inert gas to form a coating on the conductive support. Then, a semiconductor layer (semiconductor film) is formed.
[0161]
The coating obtained by applying and drying the coating solution on the conductive support is composed of an aggregate of semiconductor fine particles, and the particle size of the fine particles corresponds to the primary particle size of the semiconductor fine powder used. is there.
[0162]
The semiconductor fine particle aggregate film thus formed on the substrate such as the conductive support has a low bonding strength with the conductive support and a low bonding strength between the fine particles, and a low mechanical strength. This is preferably performed because the semiconductor fine particle aggregate film is baked to increase the mechanical strength and become a baked product film firmly fixed to the substrate.
[0163]
In the present invention, the fired product film may have any structure, but is preferably a porous structure film (also referred to as a porous layer having voids).
[0164]
Here, the porosity of the semiconductor thin film according to the present invention is preferably 10% by volume or less, more preferably 8% by volume or less, and particularly preferably 0.01 to 5% by volume. The porosity of the semiconductor thin film means a porosity having a penetrating property in the thickness direction of the dielectric, and can be measured using a commercially available device such as a mercury porosimeter (Shimadzu Poreizer 9220).
[0165]
The thickness of the semiconductor layer which has become a fired product film having a porous structure is preferably at least 10 nm or more, more preferably 100 to 10000 nm.
[0166]
During the baking treatment, the baking temperature is preferably lower than 1000 ° C., more preferably 200 to 800 ° C., from the viewpoint of appropriately adjusting the actual surface area of the baking product film and obtaining a baking product film having the above porosity. And particularly preferably in the range of 300 to 800 ° C.
[0167]
The ratio of the actual surface area to the apparent surface area can be controlled by the particle size and specific surface area of the semiconductor fine particles, the firing temperature, and the like. After the heat treatment, for example, chemical plating using an aqueous solution of titanium tetrachloride or trichloride for the purpose of increasing the surface area of the semiconductor particles, increasing the purity in the vicinity of the semiconductor particles, and increasing the efficiency of electron injection from the dye to the semiconductor particles. Electrochemical plating using an aqueous titanium solution may be performed.
[0168]
《Semiconductor sensitization》
As described above, the sensitization treatment of a semiconductor is performed by dissolving a dye in an appropriate solvent and immersing the substrate obtained by firing the semiconductor in the solution. In that case, the substrate on which the semiconductor layer (also referred to as a semiconductor film) is formed by firing is subjected to a reduced pressure treatment or a heat treatment in advance to remove bubbles in the film, and the above general formulas (1) to (5) It is preferable to allow the compound represented by the following formula to penetrate deep inside the semiconductor layer (semiconductor film), and it is particularly preferable when the semiconductor layer (semiconductor film) is a porous structure film.
[0169]
"solvent"
The solvent used for dissolving the compound represented by the general formula (1) is specially selected as long as it can dissolve the compound and does not dissolve the semiconductor or react with the semiconductor. Although there is no limitation, in order to prevent water and gas dissolved in the solvent from entering the semiconductor film and hinder sensitization treatment such as adsorption of the compound, degassing and purification by distillation are performed in advance. preferable.
[0170]
In dissolving the compound, a solvent preferably used is an alcohol solvent such as methanol, ethanol, or n-propanol; a ketone solvent such as acetone or methyl ethyl ketone; or an ether solvent such as diethyl ether, diisopropyl ether, tetrahydrofuran, or 1,4-dioxane. Solvents, halogenated hydrocarbon solvents such as methylene chloride and 1,1,2-trichloroethane, and particularly preferably methanol, ethanol, acetone, methyl ethyl ketone, tetrahydrofuran, and methylene chloride.
[0171]
《Temperature and time of sensitization treatment》
The time for immersing the substrate after baking the semiconductor in the solution containing the compound represented by the general formula (1) is such that the compound penetrates deeply into the semiconductor layer (semiconductor film) to sufficiently promote adsorption and the like. Is sufficiently sensitized, and from the viewpoint of preventing the decomposition product from being generated by the decomposition of the compound in the solution or the like and hindering the adsorption of the compound, it is preferably 3 to 48 hours under the condition of 25 ° C. And more preferably for 4 to 24 hours. This effect is particularly remarkable when the semiconductor film has a porous structure. However, the immersion time is a value under the condition of 25 ° C., and is not limited to the above when the temperature condition is changed.
[0172]
Upon immersion, the solution containing the compound represented by the general formula (1) may be heated to a temperature at which it does not boil, as long as the compound does not decompose. The preferred temperature range is from 10 to 100 ° C, more preferably from 25 to 80 ° C, but not limited to the case where the solvent boils within the above-mentioned temperature range as described above.
[0173]
《Photoelectric conversion element》
The photoelectric conversion element of the present invention will be described with reference to FIG.
[0174]
FIG. 1 is a partial sectional view showing an example of the structure of the photoelectric conversion element of the present invention.
1 denotes a conductive support, 2 denotes a photosensitive layer, 3 denotes a charge transfer layer, and 4 denotes a counter electrode. The conductive support 1 and the photosensitive layer 2 are also referred to as a semiconductor electrode.
[0175]
Here, the photosensitive layer 2 is a layer having the semiconductor for a photoelectric conversion material of the present invention, and the charge transfer layer 3 usually contains a redox electrolyte and is in contact with the conductive support 1, the photosensitive layer 2, and the counter electrode 4. Used in form.
[0176]
<< Method of manufacturing photoelectric conversion element >>
A method for manufacturing a photoelectric conversion element will be described with reference to FIG.
[0177]
In the photoelectric conversion element of the present invention, the semiconductor thin film is formed on the conductive support 1 as shown in FIG. 1 by using the plasma processing apparatus as described above, and then the general formula (1) according to the present invention is obtained. It is manufactured through a process of adsorbing the compound represented by
[0178]
Further, for the purpose of increasing the surface area of the semiconductor thin film or removing impurities and the like on the surface of the semiconductor thin film, the purity of the semiconductor is increased, and the efficiency of electron injection from the compound represented by the general formula (1) into the semiconductor is increased. For example, chemical plating using an aqueous solution of titanium tetrachloride or electrochemical plating using an aqueous solution of titanium trichloride may be performed.
[0179]
The compound represented by the general formula (1) described above is adsorbed on the semiconductor film formed on the conductive support 1, and the semiconductor film is sensitized to form the photosensitive layer 2. As described above, the sensitization treatment is performed by dissolving the compound in an appropriate solvent and immersing the semiconductor film formed on the conductive support 1 in the solution. At that time, the semiconductor film is previously subjected to a reduced pressure treatment or a heat treatment to remove bubbles in the film, so that the compound represented by the general formula (1) can enter deep inside the semiconductor film. Is preferred.
[0180]
When the compound represented by the general formula (1) is adsorbed on the semiconductor according to the present invention, it may be used alone or in combination. Further, conventionally known sensitizing dye compounds (for example, U.S. Pat. Nos. 4,684,537, 4,927,721, 5,084,365, 5,350,644, and 5,463,057, 5,525,440, JP-A-7-249790, and JP-A-2000-150007).
[0181]
In particular, when the semiconductor is used for a solar cell, it is preferable to use a mixture of two or more dyes so that the wavelength range of photoelectric conversion is widened and sunlight can be used as effectively as possible.
[0182]
The semiconductor for a photoelectric conversion material sensitized by using a plurality of the compounds represented by the general formula (1) described above in combination may be prepared by immersing the semiconductor in a solution prepared by mixing the compounds used in combination. Alternatively, a solution may be prepared for each compound and immersed in each solution in order.
[0183]
When preparing separate solutions for each compound and immersing them in each solution in order, the effects of the present invention can be achieved in any order in which the compound or the conventionally known sensitizing dye is adsorbed on the semiconductor. Can be obtained.
[0184]
In the adsorption treatment, a solution in which the compound is dissolved may be used at room temperature, or the solution may be heated to a temperature that does not affect the compound. Further, it is preferable to remove the dye that has not been adsorbed during the adsorption treatment by washing with a solvent or the like.
[0185]
After the dye is adsorbed on the semiconductor film formed on the conductive support 1 to form the photosensitive layer 2, the opposing electrode 4 is disposed so as to face the photosensitive layer 2. Further, a redox electrolyte as a charge transfer layer is injected between the semiconductor electrode and the counter electrode 4 to obtain a photoelectric conversion element.
[0186]
《Solar cell》
The solar cell of the present invention will be described.
[0187]
As shown in FIG. 1, the solar cell of the present invention, as one embodiment of the photoelectric conversion element of the present invention, has an optimal design and circuit design for sunlight, and is optimal when solar light is used as a light source. It has a structure in which photoelectric conversion is performed. That is, the structure is such that the semiconductor for the photoelectric conversion material can be irradiated with sunlight. In configuring the solar cell of the present invention, it is preferable that the semiconductor electrode, the charge transfer layer, and the counter electrode are housed in a case and sealed, or the whole thereof is sealed with a resin.
[0188]
When the solar cell of the present invention is irradiated with sunlight or an electromagnetic wave equivalent to sunlight, the compound of the present invention adsorbed on the semiconductor for a photoelectric conversion material absorbs the irradiated light or electromagnetic wave and is excited. The electrons generated by the excitation move to the semiconductor, and then move to the counter electrode 4 via the conductive support 1 to reduce the redox electrolyte of the charge transfer layer 3. On the other hand, the compound of the present invention in which electrons have been transferred to the semiconductor is in an oxidized form, but is reduced by the supply of electrons from the counter electrode 4 via the redox electrolyte of the charge transfer layer 3 to be reduced to the original form. At the same time, the redox electrolyte of the charge transfer layer 3 is oxidized and returns to a state where it can be reduced again by the electrons supplied from the counter electrode 4. In this manner, electrons flow and a solar cell using the photoelectric conversion element of the present invention can be formed.
[0189]
《Conductive support》
The conductive support used in the photoelectric conversion element of the present invention or the solar cell of the present invention is provided with a conductive material such as a metal plate or a non-conductive material such as a glass plate or a plastic film. Can be used. Examples of the material used for the conductive support include a metal (for example, platinum, gold, silver, copper, aluminum, rhodium, indium) or a conductive metal oxide (for example, indium-tin composite oxide, tin oxide and fluorine). And carbon). The thickness of the conductive support is not particularly limited, but is preferably 0.3 to 5 mm.
[0190]
The conductive support is preferably substantially transparent, and substantially transparent means that the light transmittance is 10% or more, more preferably 50% or more, and 80% or more. % Is most preferable. In order to obtain a transparent conductive support, it is preferable to provide a conductive layer made of a conductive metal oxide on the surface of a glass plate or a plastic film. When the transparent conductive support 1 is used, it is preferable that light is incident from the support side.
[0191]
The conductive support has a surface resistance of 50Ω / cm. ² Preferably 10 Ω / cm ² It is more preferred that:
[0192]
《Charge transfer layer》
The charge transfer layer used in the present invention will be described.
[0193]
A redox electrolyte is preferably used for the charge transfer layer. Here, as the redox electrolyte, I ⁻ / I ^3- System, Br ⁻ / Br ^3- System, quinone / hydroquinone system and the like. Such a redox electrolyte can be obtained by a conventionally known method. ⁻ / I ^3- The system electrolyte can be obtained by mixing iodine with an ammonium salt of iodine. The charge transfer layer is composed of a dispersion of these redox electrolytes, and these dispersions are dispersed in a liquid electrolyte in the case of a solution, and in a solid polymer electrolyte or a gel substance when dispersed in a polymer that is solid at ordinary temperature. When done, it is called a gel electrolyte. When a liquid electrolyte is used as the charge transfer layer, an electrochemically inert solvent is used as the solvent, for example, acetonitrile, propylene carbonate, ethylene carbonate, or the like. Examples of the solid polymer electrolyte include the electrolyte described in JP-A-2001-160427, and examples of the gel electrolyte include the electrolyte described in “Surface Science”, Vol. 21, No. 5, pp. 288-293.
[0194]
《Counter electrode》
The counter electrode used in the present invention will be described.
[0195]
The counter electrode may have any conductivity, and any conductive material may be used. ^3- It is preferable to use one having a catalytic ability to cause oxidation of ions or the like or reduction reaction of other redox ions at a sufficient speed. Examples of such a material include a platinum electrode, a material obtained by performing platinum plating or platinum deposition on a conductive material surface, rhodium metal, ruthenium metal, ruthenium oxide, carbon, and the like.
[0196]
【Example】
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.
[0197]
Example 1
<< Preparation of photoelectric conversion element 1 >>
A photoelectric conversion device as shown in FIG. 1 was produced as described below.
[0198]
62.5 ml of titanium tetraisopropoxide (primary grade, manufactured by Wako Pure Chemical Industries, Ltd.) was dropped into 375 ml of pure water at room temperature with vigorous stirring for 10 minutes (a white precipitate was formed), and then 70% by mass nitric acid aqueous solution. Was added and the reaction system was heated to 80 ° C., and then stirring was continued for 8 hours. After the reaction mixture was concentrated under reduced pressure until the volume of the reaction mixture became about 200 ml, 125 ml of pure water and 140 g of titanium oxide powder (Super Titania F-6 manufactured by Showa Titanium Co.) were added, and a titanium oxide suspension (about 800 ml) was added. Was prepared. A titanium oxide suspension was applied on a transparent conductive glass plate coated with fluorine-doped tin oxide, and dried naturally, followed by baking at 300 ° C. for 60 minutes to form a film-like titanium oxide on the support. .
[0199]
Then, a solution in which 5 g of Exemplified Compound I-1 was dissolved in 200 ml of a methanol solution was prepared, and the above-mentioned film-form titanium oxide (semiconductor layer for a photoelectric conversion material) was immersed together with the support, and 1 g of trifluoroacetic acid was further added thereto. Ultrasonic irradiation was performed for hours. After the reaction, the film-like titanium oxide (semiconductor layer for photoelectric conversion material) was washed with chloroform and dried in vacuum to prepare a photosensitive layer 2 (semiconductor for photoelectric conversion material).
[0200]
As the counter electrode 4, a transparent conductive glass plate coated with fluorine-doped tin oxide and further supporting platinum thereon is used, and the volume ratio between the conductive support 1 and the counter electrode 4 is 1 Redox electrolyte prepared by dissolving tetrapropylammonium iodide and iodine at a concentration of 0.46 mol / l and 0.06 mol / l respectively in a mixed solvent of acetonitrile / ethylene carbonate of 4: The charge transfer layer 3 was manufactured, and the photoelectric conversion element 1 was manufactured.
[0201]
<< Preparation of photoelectric conversion elements 2-55 >>: The present invention
Photoelectric conversion elements 2 to 55 were obtained in the same manner as in the production of photoelectric conversion element 1, except that Exemplified Compound I-1 was changed to the compounds described in Tables 1 and 2.
[0202]
<< Preparation of Photoelectric Conversion Elements R1 and R2 >>: Comparative Example
Photoelectric conversion elements R1 and R2 were obtained in the same manner as in production of photoelectric conversion element 1, except that comparative compounds R1 and R2 shown in Tables 1 and 2 were used.
[0203]
Embedded image

[0204]
<< Production of solar cells SC-1 to SC-55 >>: The present invention
After enclosing the side surfaces of the photoelectric conversion elements 1 to 55 with resin, lead wires were attached, and solar cells SC-1 to SC-55 were manufactured in three lots.
[0205]
<< Preparation of Solar Cells SC-R1 and R2 >>: Comparative Example
In the above-described production of solar cell SC-1, three lots of solar cells SC-R1 and R2 were produced in the same manner except that comparative photoelectric conversion elements R1 and R2 were used.
[0206]
<< Evaluation of photoelectric conversion characteristics of solar cells >>
The solar cells SC-1 to SC-55 obtained above and the solar cells SC-R1 and R-R2 were each supplied with a solar simulator (manufactured by JASCO (JASCO), low-energy spectral sensitivity measuring apparatus CEP-25) at 100 mW / m. ² Current density Jsc (mA / cm ² ) And the open-circuit voltage value Voc (V) were measured, and the results are shown in Tables 1 and 2. The values were average values for three solar cells having the same configuration and manufacturing method.
[0207]
[Table 1]

[0208]
[Table 2]

[0209]
Tables 1 and 2 show that the solar cell of the present invention exhibits higher photoelectric conversion characteristics than the comparison, and it is effective to use the compound represented by the general formula (1). In particular, Q of the dye is represented by the general formula (Cp-1), (Cp-2), (Cp-3), (Cp-4), (Cp-6), (Cp-15), the general formula (4) or It can be seen that the structure represented by (5) is excellent. Moreover, the solar cells SC-1 to SC-20 of the present invention have a solar simulator of 100 mW / m ² No decrease in photoelectric conversion efficiency was observed even after 100 hours of light irradiation, and it was clear that the stability was excellent.
[0210]
【The invention's effect】
According to the present invention, a semiconductor for a photoelectric conversion material, a photoelectric conversion element, and a solar cell exhibiting high photoelectric conversion efficiency and excellent stability can be provided.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view illustrating an example of a structure of a photoelectric conversion element of the present invention.
[Explanation of symbols]
1 conductive support
2 Photosensitive layer
3 Charge transfer layer
4 Counter electrode

Claims (8)

A semiconductor for a photoelectric conversion material, comprising a dye represented by the following general formula (1).

(Wherein, A represents a 5- to 6-membered aromatic group or heterocyclic group, B ₁ and B ₂ each represent -CR ₁ = or -N =, and at least one represents -N =, R ₁ represents a hydrogen atom or a substituent, and Q is represented by the following general formulas (2) to (5), and has at least one carboxyl group in the molecule.)

(Wherein, B ₃ represents CR ₃ or a nitrogen atom, R ₂ and R ₃ each represent a hydrogen atom or a substituent, Z represents a group of atoms necessary to form a 5- or 6-membered ring, may have a substituent group having at least one carboxyl group in the molecule, binds to B ₁ in *.)

(Wherein, B ₄ represents CR ₇ or a nitrogen atom, R ₄ , R ₅ , R ₆ and R ₇ each represent a hydrogen atom or a substituent, and R ₈ represents a hydrogen atom, an alkyl group or an acyl group. , having at least one carboxyl group in the molecule, binds to B ₁ in *.) _{2. The} semiconductor for a photoelectric conversion material according to claim _1, wherein said B1 and B2 are -N =. 3. The semiconductor for a photoelectric conversion material according to claim 1, wherein A is a 6-membered aromatic group. The Q is represented by the following general formulas (Cp-1), (Cp-2), (Cp-3), (Cp-4), (Cp-6), and (Cp-15). The semiconductor for a photoelectric conversion material according to claim 1.

(Wherein, in the general formulas (Cp-1) and (Cp-2), R ₆₃ and R ₆₄ each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an acylamino group, an alkylsulfonylamino group Represents an arylsulfonylamino group, an amino group, an alkylamino group, an alkylthio group, an arylthio group, an alkoxyl group, an aryloxy group, an ureido group, an alkoxycarbonylamino group, a carbamoyl group, a carboxyl group or an alkoxycarbonyl group, and R ₆₂ represents hydrogen. Represents an atom, an alkyl group or an acyl group,
Formula (Cp-3), in _{(Cp-4), R 62} , R 63 and _{R 64,} the formula _{(Cp-1), R 62} , R 63 and _{R 64} described in (Cp-2) And R ₆₅ and R ₆₇ are each a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an amino group, an alkylthio group, an arylthio group, and an alkoxyl group. Represents an aryloxy group, a ureido group, an alkoxycarbonylamino group, an acyl group, a carboxyl group, an alkoxycarbonyl group or a carbamoyl group;
In Formula (Cp-6), R ₈₇ and R ₈₈ each represent a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group, a cyano group, or a sulfamoyl group. Represents an alkylsulfonyl group, an arylsulfonyl group or a nitro group, R ₈₉ represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group, R ₆₂ represents a hydrogen atom, an alkyl group or an acyl group,
In Formula (Cp-15), R ₉₁ represents an alkyl group, an aryl group, a heterocyclic group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group, a cyano group, a sulfamoyl group, an alkylsulfonyl group, or an arylsulfonyl group. Or a nitro group, and R ₉₃ and R ₉₄ are each a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, a ureido group, an alkoxycarbonylamino group, an alkyl or arylsulfonylamino group, a halogen atom, a carboxyl group , An amino group, an alkylthio group, an arylthio group, an alkoxyl group, or an aryloxy group, R ₆₂ represents a hydrogen atom, an alkyl group, or an acyl group, is bonded to B1 by an * part, and has at least one carboxyl group. ) Formula (Cp-1), (Cp -2), (Cp-3) in _{R 64} is a photoelectric conversion material for a semiconductor according to claim 4, characterized by being represented by the following general formula (6).

(Wherein, R ₉ or R ₁₀ represents a hydrogen atom or a substituent, n represents an integer of 0 to 3, and when n is 1 or more, R ₉ and R ₁₀ combine to form a 5- to 6-membered ring. May be used.) The semiconductor for a photoelectric conversion material according to claim 1, wherein the semiconductor for a photoelectric conversion material is a metal oxide or a metal sulfide semiconductor. A photoelectric conversion element, wherein a layer containing the semiconductor for a photoelectric conversion material according to claim 1 is provided on a conductive support. A solar cell comprising the photoelectric conversion element according to claim 7, a charge transfer layer, and a counter electrode.

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