JP4103324B2 - Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same - Google Patents
Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same Download PDFInfo
- Publication number
- JP4103324B2 JP4103324B2 JP2000330202A JP2000330202A JP4103324B2 JP 4103324 B2 JP4103324 B2 JP 4103324B2 JP 2000330202 A JP2000330202 A JP 2000330202A JP 2000330202 A JP2000330202 A JP 2000330202A JP 4103324 B2 JP4103324 B2 JP 4103324B2
- Authority
- JP
- Japan
- Prior art keywords
- electronic state
- spectrum
- titanium oxide
- twice
- per time
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 title claims description 79
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 title claims description 71
- 239000011941 photocatalyst Substances 0.000 title claims description 40
- 239000011248 coating agent Substances 0.000 title claims description 16
- 238000001228 spectrum Methods 0.000 claims description 35
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 28
- 229910052719 titanium Inorganic materials 0.000 claims description 25
- 239000010936 titanium Substances 0.000 claims description 22
- 238000000026 X-ray photoelectron spectrum Methods 0.000 claims description 18
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 17
- 229910052799 carbon Inorganic materials 0.000 claims description 16
- 238000004458 analytical method Methods 0.000 claims description 15
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 claims description 13
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 13
- 229910052760 oxygen Inorganic materials 0.000 claims description 13
- 239000001301 oxygen Substances 0.000 claims description 13
- 238000002835 absorbance Methods 0.000 claims description 12
- 239000003054 catalyst Substances 0.000 claims description 8
- 239000002904 solvent Substances 0.000 claims description 5
- 239000012298 atmosphere Substances 0.000 claims description 4
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 description 14
- 230000001699 photocatalysis Effects 0.000 description 14
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 10
- 230000003595 spectral effect Effects 0.000 description 10
- 239000000126 substance Substances 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- 239000004566 building material Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- DCKVFVYPWDKYDN-UHFFFAOYSA-L oxygen(2-);titanium(4+);sulfate Chemical compound [O-2].[Ti+4].[O-]S([O-])(=O)=O DCKVFVYPWDKYDN-UHFFFAOYSA-L 0.000 description 6
- 238000001782 photodegradation Methods 0.000 description 6
- 239000007787 solid Substances 0.000 description 6
- 229910000349 titanium oxysulfate Inorganic materials 0.000 description 6
- 239000001569 carbon dioxide Substances 0.000 description 5
- 229910002092 carbon dioxide Inorganic materials 0.000 description 5
- 230000001747 exhibiting effect Effects 0.000 description 5
- 239000011521 glass Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 230000000704 physical effect Effects 0.000 description 4
- 238000000985 reflectance spectrum Methods 0.000 description 4
- 238000000576 coating method Methods 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000006864 oxidative decomposition reaction Methods 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 241000894006 Bacteria Species 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 150000002484 inorganic compounds Chemical class 0.000 description 2
- 229910010272 inorganic material Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 238000007146 photocatalysis Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000004094 surface-active agent Substances 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- 238000000870 ultraviolet spectroscopy Methods 0.000 description 2
- 229910052724 xenon Inorganic materials 0.000 description 2
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 2
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910001040 Beta-titanium Inorganic materials 0.000 description 1
- 241000195940 Bryophyta Species 0.000 description 1
- 241000195493 Cryptophyta Species 0.000 description 1
- LLQPHQFNMLZJMP-UHFFFAOYSA-N Fentrazamide Chemical compound N1=NN(C=2C(=CC=CC=2)Cl)C(=O)N1C(=O)N(CC)C1CCCCC1 LLQPHQFNMLZJMP-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 241000208125 Nicotiana Species 0.000 description 1
- 235000002637 Nicotiana tabacum Nutrition 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 1
- IKHGUXGNUITLKF-XPULMUKRSA-N acetaldehyde Chemical compound [14CH]([14CH3])=O IKHGUXGNUITLKF-XPULMUKRSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 150000001299 aldehydes Chemical class 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000005457 ice water Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- SOQBVABWOPYFQZ-UHFFFAOYSA-N oxygen(2-);titanium(4+) Chemical class [O-2].[O-2].[Ti+4] SOQBVABWOPYFQZ-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 239000002952 polymeric resin Substances 0.000 description 1
- 239000005297 pyrex Substances 0.000 description 1
- 230000002285 radioactive effect Effects 0.000 description 1
- 230000001603 reducing effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
Images
Landscapes
- Catalysts (AREA)
- Paints Or Removers (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は酸化チタン、それを用いてなる光触媒体及び光触媒体コーティング剤に関するものである。
【０００２】
【従来の技術】
半導体に紫外線を照射すると強い還元作用を持つ電子と強い酸化作用を持つ正孔が生成し、半導体に接触した分子種を酸化還元作用により分解する。このような作用を光触媒作用と呼び、この光触媒作用を利用することによって、居住空間や作業空間での悪臭物質の分解除去、あるいは水中の有機溶剤や農薬、界面活性剤等の分解除去を行うことができる。光触媒作用を示す物質として酸化チタンが注目され、酸化チタンからなる光触媒体が市販されている。
【０００３】
しかしながら、現在市販されている酸化チタンからなる光触媒体は、可視光線を照射する場合には十分な光触媒作用を示すものではなかった。
【０００４】
【発明が解決しようとする課題】
本発明の課題は、可視光線を照射することにより高い光触媒作用を示す光触媒体、その触媒成分としての酸化チタン、及びコーティング剤としての光触媒体コーティング剤を提供することにある。
【０００５】
【課題を解決するための手段】
本発明者等は上記課題を解決すべく鋭意検討を行った結果、可視光線を照射することにより高い光触媒作用を示す光触媒体に適する触媒成分としての酸化チタンを見出し、本発明を完成するに至った。
【０００６】
本発明は、Ｘ線光電子分光法により８回分析し、チタンの電子状態について、１回目と２回目の分析の積算スペクトル及び７回目と８回目の分析の積算スペクトルを求め、それぞれの積算スペクトルのうち結合エネルギー４５８ｅＶ〜４６０ｅＶにあるピークを求め、１回目と２回目の分析の積算スペクトルにあるピークの半価幅をＡ1とし、７回目と８回目の分析の積算スペクトルにあるピークの半価幅をＢ1としたとき、式（Ｉ）
Ｘ1＝Ｂ1／Ａ1 （Ｉ）
により算出される指数Ｘ1が０．９以下であり、かつ、紫外可視拡散反射スペクトルを測定して、波長２５０ｎｍ〜５５０ｎｍの吸光度の積分値をＣ1とし、波長４００ｎｍ〜５５０ｎｍの吸光度の積分値をＤ1としたとき、式（II）
Ｙ1＝Ｄ1／Ｃ1 （II）
により算出される指数Ｙ1が０．１４５以上であることを特徴とする酸化チタンを提供するものである。〔ただし、結合エネルギー４５８ｅＶ〜４６０ｅＶにあるピークの半価幅は、光電子分光測定装置（ピーク位置を決めるための基準には炭素を使用し、Ｘ線源としてＭｇＫα ８ｋＶ ３０ｍＡを使用する。）を用い、酸化チタンについて、チタンの電子状態を１回あたり６０秒で２回分析（１回目、２回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（３回目、４回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（５回目、６回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（７回目、８回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、を順に行って各々Ｘ線光電子分光スペクトルを求め、ここで前記の一連の分析は、分析時及び分析と分析との間、酸化チタンを大気中に暴露させることなく行い、開始から終了迄の時間が３０分以内となるように行い、その後、チタンの電子状態についての１回目のＸＰＳスペクトルと２回目のＸ線光電子分光スペクトルとを積算して、及び７回目のＸ線光電子分光スペクトルと８回目のＸ線光電子分光スペクトルとを積算して求める。吸光度の積分値は、縦軸を吸光度とし、横軸を波長とした紫外可視拡散反射スペクトルにおいて、指定された波長の範囲内で横軸と拡散反射スペクトルとで囲まれた領域の面積を示す。〕
【０００７】
また、本発明は、前記酸化チタンを含む光触媒体を提供するものである。
【０００８】
さらに、本発明は、前記酸化チタンと溶媒とを含む光触媒体コーティング剤を提供するものである。
【０００９】
【発明の実施の形態】
酸化チタンはＴｉＯ2なる組成式を有し、その化学組成自体はもちろん公知であるが、本発明では、その中のチタン原子の特定の電子状態にあるものが見出されたのである。すなわち、酸化チタンをＸ線光電子分光法（以下、ＸＰＳという。）により８回分析して、チタンの電子状態についての１回目と２回目の積算スペクトル及び７回目と８回目の積算スペクトルのうち、結合エネルギー４５８ｅＶ〜４６０ｅＶにあるそれぞれのピークを求め、１回目と２回目の積算スペクトルにあるピークの半価幅Ａ1及び７回目と８回目の積算スペクトルにあるピークの半価幅Ｂ1から、前記式（I）により算出される指数Ｘ1を酸化チタン中のチタン原子の電子状態を示す指標とする。チタン原子の電子状態は結合エネルギーで示すことができ、一般には、指数Ｘ1が小さいほど、結合エネルギーの高い電子をもつチタン原子と結合エネルギーの低い電子をもつチタン原子とから構成され、Ｘ線の繰り返し照射により結合エネルギーの高い電子をもつチタン原子が減少することになり、一方、指数Ｘ1が大きければ、結合エネルギーの高い電子をもたないチタン原子から構成されていることになる。そこで本発明では、指数Ｘ1が０．９以下であることを一つの要件とする。
【００１０】
積算スペクトルは、光電子分光測定装置（ピーク位置を決めるための基準には炭素を使用する。）を用い、酸化チタンについて、チタンの電子状態を１回あたり６０秒で２回分析（１回目、２回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（３回目、４回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（５回目、６回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（７回目、８回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、を順に行って各々ＸＰＳスペクトルを求めた後、チタンの電子状態についての１回目のＸＰＳスペクトルと２回目のＸＰＳスペクトルとを積算して、及び７回目のＸＰＳスペクトルと８回目のＸＰＳスペクトルとを積算して求めることができる。前記の一連の分析は、分析時及び分析と分析との間、酸化チタンを大気中に暴露させることなく行い、開始から終了迄の時間が３０分以内となるように行う。
【００１１】
半価幅は、得られた積算スペクトルのピークから求めることができる。詳細には、積算スペクトルのピークの中で、結合エネルギー４５８ｅＶ〜４６０ｅＶにあるチタンのピークから求めることができる。結合エネルギー４５８ｅＶ〜４６０ｅＶにチタンのピークが２つ以上ある場合、それらピークの中で最も高いピークから求めることができる。
【００１２】
本発明の酸化チタンを特定するもう一つの要件は、紫外可視拡散反射スペクトルを測定して、波長２５０ｎｍ〜５５０ｎｍの吸光度の積分値及び波長４００ｎｍ〜５５０ｎｍの吸光度の積分値を求め、前者の積分値をＣ1とし、後者の積分値をＤ1としたとき、前記式（II）により算出される指数Ｙ1である。この指数Ｙ1は可視光線に対する酸化チタンの吸収能力を示す指標となる。そこで本発明では、指数Ｙ1が０．１４５以上であることをもう一つの要件とする。
【００１３】
吸光度の積分値とは、縦軸を吸光度とし、横軸を波長とした紫外可視拡散反射スペクトルにおいて、指定された波長の範囲内で横軸と拡散反射スペクトルとで囲まれた領域の面積を示す。紫外可視拡散反射スペクトルは、例えば、紫外可視分光光度計を用い、硫酸バリウムを標準白板として測定することができる。
【００１４】
本発明の酸化チタンは、結晶子の大きさをＥ1としたとき、式（III）
Ｚ1＝Ｙ1×Ｅ1 （III）
〔式（III）中、Ｙ1は式（II）により算出される指数を表す。〕
により算出される指数Ｚ1が０．７５以上であることが好ましい。また、指数Ｚ1は１．５以上、さらには１．８以上であることがより好ましい。結晶子の大きさＥ1は、例えば、Ｘ線回折装置を用い、酸化チタンの最強干渉線（面指数１０１）のピークの半価幅とピーク位置（ブラッグ角）を求め、Ｓｃｈｅｒｒｅｒの式により算出することができる。
【００１５】
本発明の酸化チタンは、結晶子の大きさをＥ1とし、アナターゼ化率をＦ1としたとき、式（IV）
Ｗ1＝Ｙ1×Ｅ1×Ｆ1 （IV）
〔式（IV）中、Ｙ1は前記式（II）により算出される指数を表す。〕
により算出される指数Ｗ1が０．４以上であることが好ましい。また、指数Ｗ1は１．３以上、さらには１．８以上であることがより好ましい。アナターゼ化率Ｆ1は、例えば、Ｘ線回折装置を用い、酸化チタンの最強干渉線（面指数１０１）のピーク面積を求め、算出することができる。
【００１６】
本発明の酸化チタンの形状は、使用方法により異なり一義的ではないが、例えば、粒子状、繊維状等が挙げられる。また、酸化チタンには、可視光線の照射による光触媒活性を損なわせない範囲で他の無機化合物を混合してもよいし、又は混合した後、熱処理等して混合物を複合化してもよい。他の無機化合物としては、例えばシリカ（ＳｉＯ2）、アルミナ（Ａｌ2Ｏ3）、ジルコニア（ＺｒＯ2）、マグネシア（ＭｇＯ）、酸化亜鉛（ＺｎＯ）、酸化鉄（Ｆｅ2Ｏ3、Ｆｅ3Ｏ4）等が挙げられる。
【００１７】
本発明による特定のＸＰＳスペクトル特性及び紫外可視拡散反射スペクトル特性を示す酸化チタンは、例えば、オキシ硫酸チタンを水に溶解し、冷却しながらその水溶液に塩基を添加して固形物を沈澱させ、得られた固形物を焼成する方法によって製造することができる。
【００１８】
本発明の光触媒体は、触媒成分として、前述した特定のＸＰＳスペクトル特性及び紫外可視拡散反射スペクトル特性を示す酸化チタンを含む。
【００１９】
この光触媒体としては、例えば、粒子状酸化チタンに成形助剤を添加した後、押出成形して得られたシート状光触媒体、繊維状酸化チタンと有機繊維とを交絡させて得られたシート状光触媒体、金属製又は樹脂製の支持体に酸化チタンを塗布又は被覆して得られたもの等が挙げられる。また、この光触媒体は、高分子樹脂、成形助剤、結合剤、帯電防止剤、吸着剤等を添加して用いてもよく、また紫外線の照射に対し光触媒活性を有する他の酸化チタン等と併用してもよい。
【００２０】
この光触媒体の使用に際しては、例えば、可視光線を透過するガラス製容器に光触媒体と被処理液又は被処理気体等とを入れ、光源を用いて光触媒体に波長が４３０ｎｍ以上である可視光線を照射すればよい。照射時間は、光源の光線の強度、及び被処理液等の中の被処理物質の種類や量により適宜選択すればよい。
【００２１】
用いる光源としては、波長が４３０ｎｍ以上である可視光線を含む光線を照射できるものであれば制限されるものではなく、例えば太陽光線、蛍光灯、ハロゲンランプ、ブラックライト、キセノンランプ、水銀灯、ナトリウムランプ等が適用できる。また、光源には必要に応じて紫外線カットフィルター及び／又は赤外線カットフィルターを装着してもよい。
【００２２】
本発明の光触媒体コーティング剤は、前述した特定のＸＰＳスペクトル特性及び紫外可視拡散反射スペクトル特性を示す酸化チタンと溶媒とを含む。
【００２３】
この光触媒体コーティング剤は、建築材料、自動車材料等に酸化チタンを塗布すること、又は建築材料、自動車材料等を酸化チタンで被覆することを容易にし、かつ建築材料、自動車材料等に高い光触媒活性を付与することを可能とする。溶媒としては、塗布後又は被覆後に蒸発して酸化チタンに残存しない溶媒が好ましく、例えば、水、塩酸、アルコール類、ケトン類等が挙げられる。
【００２４】
この光触媒体コーティング剤は、例えば、酸化チタンを水に分散させてスラリー化する方法、酸化チタンを酸等で解膠させる方法等によって製造することができる。分散に際しては、必要に応じて分散剤を添加してもよい。
【００２５】
【実施例】
以下、実施例により本発明をさらに詳細に説明する。これら実施例では、アセトアルデヒドの光分解作用で光触媒活性を評価しているが、本発明は本実施例に限定されるものではない。尚、酸化チタンのＸ線光電子分光スペクトル、紫外可視拡散反射スペクトル、結晶子の大きさ及びアナターゼ化率の測定は以下の方法で行った。
【００２６】
Ｘ線光電子分光スペクトル：
光電子分光測定装置（理学電機製、商品名：ＸＰＳ−７０００、Ｘ線源：ＭｇＫα ８ｋＶ ３０ｍＡ、ナロースキャン、ｐａｓｓ Ｅ＝１０ｅＶ、ｓｔｅｐ
Ｅ＝０．０４ｅＶ）を用いて行った。
【００２７】
紫外可視拡散反射スペクトル：
紫外可視分光光度計（島津製作所製、商品名：ＵＶ−２５００ＰＣ）を用いて行った。
【００２８】
結晶子の大きさ：
Ｘ線回折装置（理学電機製、商品名：ＲＡＤ−ＩＩＡ）を用い、所定の条件（Ｘ線管球：Ｃｕ、管電圧：４０ｋＶ、管電流：３５ｍＡ、発散スリット：１度、散乱スリット：１度、受光スリット：０．３０ｍｍ、サンプリング幅：０．０２０度、走査速度：２．００度／分，測定積算回数：１回）で測定して、酸化チタンの最強干渉線（面指数１０１）のピークの半価幅β（ラジアン）とピーク位置２θ（ラジアン）を求め、Ｓｃｈｅｒｒｅｒの式（V）により結晶子の大きさＥ1を算出した。
Ｅ1（ｎｍ）＝Ｋ・λ／（βｃｏｓθ） （V）
〔式（V）中、Ｋは定数０．９４、λ（ｎｍ）は測定Ｘ線波長（ＣｕＫα線：０．１５４０５６ｎｍ）を表す。〕
【００２９】
アナターゼ化率：
Ｘ線回折装置（理学電機製、商品名：ＲＡＤ−ＩＩＡ）を用い、結晶子の大きさを求めるときと同じ条件で測定して、酸化チタンの最強干渉線（面指数１０１）のピーク面積を求め、アナターゼ化率を算出した。尚、標準試料には、アナターゼ型酸化チタン（チタン工業製、商品名：ＳＴＴ−６５Ｃ―Ｓ）を用い、そのアナターゼ化率を１（１００％）とした。
【００３０】
また、酸化チタンの光触媒活性を評価するための可視光線の照射には、図１に示す分光特性を有する紫外線カットフィルター（東芝硝子製、商品名Ｙ−４５）と図２に示す分光特性を有する赤外線カットフィルター（ウシオ電機製、商品名スーパーコールドフィルター）とを装着した５００Ｗキセノンランプ（ウシオ電機製、商品名オプティカルモジュレックスＳＸ−ＵＩ５００ＸＱ、ランプＵＸＬ−５００ＳＸ）を光源として用いた。
【００３１】
実施例１
１Ｌフラスコに水３６０ｇを入れた後、攪拌下でオキシ硫酸チタン（添川理化学製、商品名：オキシ硫酸チタン）９０ｇを混合し溶解した。次いで、氷水で冷却しながら２５％アンモニア水（和光純薬製、特級）１０１ｇを２２分で滴下して固形物を沈澱させ、固形物を濾過、乾燥した。次いで、得られた乾燥物を３５０℃の空気中で１時間焼成して、粒子状酸化チタンを得た。得られた酸化チタンの結晶構造はアナターゼ型であった。この酸化チタンの物性を表１に、ＸＰＳスペクトルを図３に示す。
【００３２】
次いで、密閉式のパイレックスガラス（商標）製反応容器（直径８ｃｍ×高さ１０ｃｍ、容量約０．５リットル）内に、直径５ｃｍのガラス製シャーレを設置し、そのシャーレ上に、粒子状酸化チタンだけからなる光触媒体０．３ｇを置いた。反応容器内を混合ガス（酸素と窒素との体積比が１：４である。）で満たし、アセトアルデヒド４．５μｍｏｌを封入し、波長が４３０ｎｍ以上である可視光線の照射を行った。光触媒体のアセトアルデヒドに対する光分解作用を、照射により生成したアセトアルデヒドの酸化分解生成物である二酸化炭素の濃度を光音響マルチガスモニタ（ＩＮＮＯＶＡ製、１３１２型）を用いて測定することによって、評価した。二酸化炭素の生成速度は触媒１ｇあたり１９．３６μｍｏｌ／ｈであった。
【００３３】
実施例２
５００ｍＬナス型フラスコに水７０ｇを入れた後、攪拌下でオキシ硫酸チタン（添川理化学製、商品名：オキシ硫酸チタン）３０ｇを混合し溶解した。次いで、エバポレーター（６０℃）にてオキシ硫酸チタン換算で８６．９ｗｔ％まで濃縮し、冷凍庫で−２５℃に冷却しながら２５％アンモニア水（和光純薬製：特級）１３７ｇを５秒間で滴下し固形物を沈澱させ、固形物を濾過、乾燥した。次いで、得られた乾燥物を４００℃の空気中で１時間焼成して、粒子状酸化チタンを得た。得られた酸化チタンの結晶構造はアナターゼ型であった。この酸化チタンの物性を表１に、ＸＰＳスペクトルを図４に示す。
【００３４】
次いで、実施例１と同様にしてアセトアルデヒドに対する光分解作用を評価した。二酸化炭素の生成速度は触媒１ｇあたり４３．１５μｍｏｌ／ｈであった。
【００３５】
比較例１
β−水酸化チタン（キシダ化学製）を４００℃の空気中で１時間焼成して、酸化チタンを得た。得られた酸化チタンの結晶構造はアナターゼ型であった。この酸化チタンの物性を表１に、ＸＰＳスペクトルを図５に示す。
【００３６】
次いで、実施例１と同様にしてアセトアルデヒドに対する光分解作用を評価した。二酸化炭素の生成速度は触媒１ｇあたり０．９３μｍｏｌ／ｈであった。
【００３７】
比較例２
実施例１において、市販の酸化チタン（デグッサ製、商品名Ｐ−２５）だけからなる光触媒体を用いた以外は、実施例１と同様にして行った。二酸化炭素の生成速度は触媒１ｇあたり０．０μｍｏｌ／ｈであった。この酸化チタンの物性を表１に、ＸＰＳスペクトルを図６に示す。
【００３８】
【表１】
実施例３
水に実施例１で得られた粒子状酸化チタンを分散させて光触媒体コーティング剤を調製した。得られた光触媒体コーティング剤を自動車用ガラスに塗布し、乾燥することによって自動車ガラス表面に均一に酸化チタンの層が形成された。
【００４０】
本発明の光触媒体は、波長が４３０ｎｍ以上である可視光線を照射したときのアセトアルデヒドに対する酸化分解について、市販の酸化チタンだけからなる光触媒体に比べてその酸化分解作用（光触媒作用）に優れる。
【００４１】
【発明の効果】
本発明の酸化チタンは、波長が４３０ｎｍ以上である可視光線の照射により高い光触媒作用を示す。本発明の光触媒体（酸化チタンだけからなる光触媒体を含む。）は、酸化チタンの高い光触媒作用により、アセトアルデヒド等のアルデヒド類をはじめ各種有機物を分解する。本発明の光触媒体コーティング剤は、建築材料、自動車材料等に酸化チタンを塗布すること、又は建築材料、自動車材料等を酸化チタンで被覆することを容易にし、建築材料、自動車材料等に高い光触媒作用を付与することを可能とする。
【００４２】
また、本発明の光触媒体（酸化チタンだけからなる光触媒体を含む。）や光触媒体コーティング剤を塗布等した自動車材料等は、大気中のＮＯｘを分解したり、居住空間や作業空間での悪臭物質（例えば煙草臭）等を分解したり、水中の有機溶剤、農薬、界面活性剤等を分解したり、又は細菌（例えば放射菌）、藻類、黴類等の増殖を抑制することに適用可能である。
【図面の簡単な説明】
【図１】 実施例における光触媒体の光分解作用評価のための可視光線照射の際、光源に装着した紫外線カットフィルターの分光特性を示す波長−透過率線図。
【図２】 実施例における光触媒体の光分解作用評価のための可視光線照射の際、光源に装着した赤外線カットフィルターの分光特性を示す波長−透過率線図。
【図３】 実施例１で用いた酸化チタンのＸＰＳによる１回目と２回目との積算スペクトル及び７回目と８回目との積算スペクトル。
【図４】 実施例２で用いた酸化チタンのＸＰＳによる１回目と２回目との積算スペクトル及び７回目と８回目との積算スペクトル。
【図５】 比較例１で用いた酸化チタンのＸＰＳによる１回目と２回目との積算スペクトル及び７回目と８回目との積算スペクトル。
【図６】 比較例２で用いた酸化チタンのＸＰＳによる１回目と２回目との積算スペクトル及び７回目と８回目との積算スペクトル。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to titanium oxide, a photocatalyst using the same, and a photocatalyst coating agent.
[0002]
[Prior art]
When a semiconductor is irradiated with ultraviolet rays, electrons having a strong reducing action and holes having a strong oxidizing action are generated, and molecular species in contact with the semiconductor are decomposed by the redox action. Such action is called photocatalysis, and by utilizing this photocatalysis, it is possible to decompose and remove malodorous substances in living spaces and work spaces, or decompose and remove organic solvents, agricultural chemicals, surfactants, etc. in water. Can do. Titanium oxide has attracted attention as a substance exhibiting a photocatalytic action, and a photocatalyst comprising titanium oxide is commercially available.
[0003]
However, the currently commercially available photocatalyst made of titanium oxide does not exhibit a sufficient photocatalytic action when irradiated with visible light.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a photocatalyst exhibiting a high photocatalytic action when irradiated with visible light, titanium oxide as a catalyst component thereof, and a photocatalyst coating agent as a coating agent.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors have found titanium oxide as a catalyst component suitable for a photocatalyst exhibiting a high photocatalytic action by irradiation with visible light, and have completed the present invention. It was.
[0006]
The present invention is analyzed eight times by X-ray photoelectron spectroscopy, and with respect to the electronic state of titanium, the integrated spectrum of the first and second analysis and the integrated spectrum of the seventh and eighth analysis are obtained. Of these, the peak at binding energy of 458 eV to 460 eV is obtained, and the half-value width of the peak in the integrated spectrum of the first and second analysis is A 1, and the half value of the peak in the integrated spectrum of the seventh and eighth analysis is when the width B 1, formula (I)
X 1 = B 1 / A 1 (I)
And the index X 1 is 0.9 or less calculated by, and by measuring the ultraviolet-visible diffuse reflection spectrum, an integrated value of absorbance at a wavelength of 250nm~550nm and C1, the integral value of the absorbance at a wavelength 400nm~550nm When D 1 , formula (II)
Y 1 = D 1 / C 1 (II)
Titanium oxide characterized in that the index Y 1 calculated by the above is 0.145 or more is provided. [However, the half width of the peak at a binding energy of 458 eV to 460 eV is obtained by using a photoelectron spectrometer (carbon is used as a reference for determining the peak position, and MgKα 8 kV 30 mA is used as an X-ray source). For titanium oxide, the electronic state of titanium is analyzed twice at 60 seconds per time (first time and second time), the electronic state of oxygen is analyzed twice at 56 seconds per time, and the electronic state of carbon per time Analyzed twice at 80 seconds, analyzed the electronic state of titanium twice at 60 seconds per time (third and fourth times), analyzed the electronic state of oxygen twice at 56 seconds per time, and analyzed the electronic state of carbon as 1 Analyzed twice at 80 seconds per time, analyzed the electronic state of titanium twice at 60 seconds per time (5th and 6th times), analyzed the electronic state of oxygen twice at 56 seconds per time, electronic state of carbon Analyzed twice at 80 seconds per time Analyzing the electronic state of titanium twice at 60 seconds per time (7th and 8th times), analyzing the electronic state of oxygen twice at 56 seconds per time, and analyzing the electronic state of carbon at 80 seconds per time X-ray photoelectron spectroscopy spectra are obtained in order, and the series of analyzes described above is performed without exposing titanium oxide to the atmosphere during and between analyses. Until the time is within 30 minutes, and then the first XPS spectrum and the second X-ray photoelectron spectrum for the electronic state of titanium are integrated, and the seventh X-ray photoelectron spectrum is integrated. And the eighth X-ray photoelectron spectrum are integrated. The integrated value of the absorbance indicates the area of the region surrounded by the horizontal axis and the diffuse reflection spectrum within the specified wavelength range in the UV-visible diffuse reflection spectrum where the vertical axis is the absorbance and the horizontal axis is the wavelength. ]
[0007]
The present invention also provides a photocatalyst containing the titanium oxide.
[0008]
Furthermore, this invention provides the photocatalyst body coating agent containing the said titanium oxide and a solvent.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Titanium oxide has a composition formula of TiO 2 , and the chemical composition itself is of course known. However, in the present invention, a titanium oxide in a specific electronic state has been found. That is, titanium oxide was analyzed eight times by X-ray photoelectron spectroscopy (hereinafter referred to as XPS), and among the first and second integrated spectra and the seventh and eighth integrated spectra for the electronic state of titanium, The respective peaks at binding
[0010]
For the integrated spectrum, a photoelectron spectrometer (carbon is used as a reference for determining the peak position) is used, and the titanium electronic state is analyzed twice in 60 seconds per time (first time, second time). The second time), analyzing the electronic state of oxygen twice at 56 seconds per time, analyzing the electronic state of carbon twice at 80 seconds per time, analyzing the electronic state of titanium twice at 60 seconds per time (third time) 4th), analysis of the electronic state of oxygen twice at 56 seconds per time, analysis of the electronic state of carbon twice at 80 seconds per time, analysis of the electronic state of titanium twice at 60 seconds per time ( 5th and 6th), analysis of the electronic state of oxygen twice at 56 seconds per time, analysis of the electronic state of carbon twice at 80 seconds per time, and electronic state of titanium twice at 60 seconds per time Analysis (7th, 8th), oxygen electronic state 56 times In order to analyze the electronic state of carbon twice and analyze the electronic state of carbon twice at 80 seconds per time, respectively, to obtain the XPS spectrum, respectively, the first XPS spectrum and the second XPS spectrum for the electronic state of titanium And the seventh XPS spectrum and the eighth XPS spectrum can be calculated. The series of analyzes described above are performed without exposing titanium oxide to the atmosphere at the time of analysis and between analyzes, and are performed so that the time from the start to the end is within 30 minutes.
[0011]
The half width can be obtained from the peak of the obtained integrated spectrum. Specifically, it can be obtained from a peak of titanium at a binding energy of 458 eV to 460 eV among the peaks of the integrated spectrum. In the case where there are two or more titanium peaks at a binding energy of 458 eV to 460 eV, the peak can be obtained from the highest peak.
[0012]
Another requirement for specifying the titanium oxide of the present invention is to measure an ultraviolet-visible diffuse reflection spectrum to obtain an integrated value of absorbance at a wavelength of 250 nm to 550 nm and an integrated value of absorbance at a wavelength of 400 nm to 550 nm. Is an index Y 1 calculated by the above formula (II), where C 1 is the integral value of the latter and D 1 is the latter. This index Y1 is an index indicating the ability of titanium oxide to absorb visible light. Therefore, in the present invention, another requirement is that the index Y 1 is 0.145 or more .
[0013]
The integrated value of absorbance indicates the area of the region surrounded by the horizontal axis and diffuse reflectance spectrum within the specified wavelength range in the UV-visible diffuse reflectance spectrum where the vertical axis is absorbance and the horizontal axis is wavelength. . The ultraviolet-visible diffuse reflectance spectrum can be measured using, for example, an ultraviolet-visible spectrophotometer and barium sulfate as a standard white plate.
[0014]
The titanium oxide of the present invention has the formula (III) when the crystallite size is E 1.
Z 1 = Y 1 × E 1 (III)
[In Formula (III), Y 1 represents an index calculated by Formula (II). ]
It is preferable that the index Z 1 calculated by the above is 0.75 or more. The index Z 1 is more preferably 1.5 or more, and further preferably 1.8 or more. The crystallite size E 1 is calculated by, for example, the Scherrer equation using an X-ray diffractometer to obtain the half-value width and peak position (Bragg angle) of the peak of the strongest interference line (surface index 101) of titanium oxide. can do.
[0015]
The titanium oxide of the present invention has the formula (IV) when the crystallite size is E 1 and the anatase conversion rate is F 1.
W 1 = Y 1 × E 1 × F 1 (IV)
[In Formula (IV), Y 1 represents an index calculated by Formula (II). ]
It is preferable that the index W 1 calculated by the above is 0.4 or more. The index W 1 is more preferably 1.3 or more, and more preferably 1.8 or more. The anatase conversion rate F 1 can be calculated by, for example, obtaining the peak area of the strongest interference line (surface index 101) of titanium oxide using an X-ray diffractometer.
[0016]
The shape of the titanium oxide of the present invention varies depending on the method of use and is not unambiguous, but examples thereof include particles and fibers. In addition, titanium oxide may be mixed with other inorganic compounds within a range that does not impair the photocatalytic activity by irradiation with visible light, or may be mixed and then combined with heat treatment or the like. Examples of other inorganic compounds include silica (SiO 2 ), alumina (Al 2 O 3 ), zirconia (ZrO 2 ), magnesia (MgO), zinc oxide (ZnO), iron oxide (Fe 2 O 3 , Fe 3 O). 4 ).
[0017]
Titanium oxide having specific XPS spectral characteristics and ultraviolet-visible diffuse reflectance spectral characteristics according to the present invention is obtained by, for example, dissolving titanium oxysulfate in water and adding a base to the aqueous solution while cooling to precipitate a solid. It can manufacture by the method of baking the obtained solid substance.
[0018]
The photocatalyst of the present invention contains titanium oxide exhibiting the above-mentioned specific XPS spectral characteristics and ultraviolet-visible diffuse reflection spectral characteristics as a catalyst component.
[0019]
As this photocatalyst, for example, a sheet-like photocatalyst obtained by adding a molding aid to particulate titanium oxide and then extrusion molding, a sheet obtained by entanglement of fibrous titanium oxide and organic fibers Examples thereof include a photocatalyst, a metal or resin support obtained by applying or coating titanium oxide. In addition, this photocatalyst may be used with addition of a polymer resin, a molding aid, a binder, an antistatic agent, an adsorbent, etc., and other titanium oxides having photocatalytic activity against ultraviolet irradiation. You may use together.
[0020]
When using this photocatalyst, for example, a photocatalyst and a liquid to be treated or a gas to be treated are placed in a glass container that transmits visible light, and visible light having a wavelength of 430 nm or more is applied to the photocatalyst using a light source. Irradiation is sufficient. The irradiation time may be appropriately selected depending on the intensity of light from the light source and the type and amount of the substance to be treated in the liquid to be treated.
[0021]
The light source to be used is not limited as long as it can emit light including visible light having a wavelength of 430 nm or more. For example, sunlight, fluorescent lamp, halogen lamp, black light, xenon lamp, mercury lamp, sodium lamp Etc. are applicable. Further, the light source may be equipped with an ultraviolet cut filter and / or an infrared cut filter as necessary.
[0022]
The photocatalyst coating agent of the present invention contains titanium oxide and a solvent exhibiting the specific XPS spectral characteristics and ultraviolet-visible diffuse reflection spectral characteristics described above.
[0023]
This photocatalyst coating agent makes it easy to apply titanium oxide to building materials, automobile materials, etc., or to coat building materials, automobile materials, etc. with titanium oxide, and has high photocatalytic activity on building materials, automobile materials, etc. Can be granted. As the solvent, a solvent that evaporates after coating or coating and does not remain in titanium oxide is preferable, and examples thereof include water, hydrochloric acid, alcohols, and ketones.
[0024]
This photocatalyst body coating agent can be produced by, for example, a method of dispersing titanium oxide in water to form a slurry, a method of peptizing titanium oxide with an acid, or the like. In dispersing, a dispersing agent may be added as necessary.
[0025]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In these examples, the photocatalytic activity is evaluated by the photodegradation action of acetaldehyde, but the present invention is not limited to this example. In addition, the measurement of the X-ray photoelectron spectroscopic spectrum, ultraviolet-visible diffuse reflection spectrum, crystallite size, and anatase ratio of titanium oxide was performed by the following method.
[0026]
X-ray photoelectron spectrum:
Photoelectron spectrometer (trade name: XPS-7000, manufactured by Rigaku Corporation, X-ray source: MgKα 8 kV 30 mA, narrow scan, pass E = 10 eV, step
E = 0.04 eV).
[0027]
UV-visible diffuse reflectance spectrum:
An ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation, trade name: UV-2500PC) was used.
[0028]
Crystallite size:
Using an X-ray diffractometer (manufactured by Rigaku Corporation, trade name: RAD-IIA), predetermined conditions (X-ray tube: Cu, tube voltage: 40 kV, tube current: 35 mA, divergence slit: 1 degree, scattering slit: 1 , Light receiving slit: 0.30 mm, sampling width: 0.020 degree, scanning speed: 2.00 degree / minute, measurement integration number: 1 time), the strongest interference line of titanium oxide (surface index 101) The peak half width β (radian) and the peak position 2θ (radian) were obtained, and the crystallite size E 1 was calculated by Scherrer's equation (V).
E 1 (nm) = K · λ / (βcos θ) (V)
[In the formula (V), K represents a constant of 0.94, and λ (nm) represents a measured X-ray wavelength (CuKα ray: 0.154056 nm). ]
[0029]
Anatase rate:
Using an X-ray diffractometer (trade name: RAD-IIA, manufactured by Rigaku Corporation), the peak area of the strongest interference line (surface index 101) of titanium oxide is measured under the same conditions as when the crystallite size is determined. The anatase conversion rate was calculated. As a standard sample, anatase-type titanium oxide (manufactured by Titanium Industry, trade name: STT-65C-S) was used, and the anatase conversion rate was set to 1 (100%).
[0030]
Further, the irradiation with visible light for evaluating the photocatalytic activity of titanium oxide has an ultraviolet cut filter (trade name Y-45, manufactured by Toshiba Glass Co., Ltd.) having the spectral characteristics shown in FIG. 1 and the spectral characteristics shown in FIG. A 500 W xenon lamp (USHIO, trade name Optical Modlex SX-UI500XQ, lamp UXL-500SX) equipped with an infrared cut filter (USHIO, trade name Super Cold Filter) was used as a light source.
[0031]
Example 1
After adding 360 g of water to a 1 L flask, 90 g of titanium oxysulfate (trade name: titanium oxysulfate, manufactured by Soekawa Richemical Co., Ltd.) was mixed and dissolved under stirring. Next, while cooling with ice water, 101 g of 25% aqueous ammonia (manufactured by Wako Pure Chemicals, special grade) was added dropwise over 22 minutes to precipitate the solid, and the solid was filtered and dried. Next, the obtained dried product was fired in air at 350 ° C. for 1 hour to obtain particulate titanium oxide. The crystal structure of the obtained titanium oxide was anatase type. The physical properties of this titanium oxide are shown in Table 1, and the XPS spectrum is shown in FIG.
[0032]
Next, a glass petri dish having a diameter of 5 cm is placed in a sealed Pyrex glass (trademark) reaction vessel (diameter 8 cm × height 10 cm, capacity of about 0.5 liter), and particulate titanium oxide is placed on the petri dish. 0.3 g of a photocatalyst consisting only of was placed. The inside of the reaction vessel was filled with a mixed gas (volume ratio of oxygen and nitrogen is 1: 4), 4.5 μmol of acetaldehyde was enclosed, and irradiation with visible light having a wavelength of 430 nm or more was performed. The photodegradation action of the photocatalyst on acetaldehyde was evaluated by measuring the concentration of carbon dioxide, which is an oxidative decomposition product of acetaldehyde generated by irradiation, using a photoacoustic multigas monitor (INNOVA, Model 1312). The production rate of carbon dioxide was 19.36 μmol / h per gram of catalyst.
[0033]
Example 2
After adding 70 g of water to a 500 mL eggplant-shaped flask, 30 g of titanium oxysulfate (trade name: titanium oxysulfate, manufactured by Soekawa Rikagaku) was mixed and dissolved under stirring. Next, it was concentrated to 86.9 wt% in terms of titanium oxysulfate using an evaporator (60 ° C), and 137 g of 25% aqueous ammonia (manufactured by Wako Pure Chemicals: special grade) was added dropwise over 5 seconds while cooling to -25 ° C in a freezer. The solid was precipitated and the solid was filtered and dried. Subsequently, the obtained dried product was fired in air at 400 ° C. for 1 hour to obtain particulate titanium oxide. The crystal structure of the obtained titanium oxide was anatase type. The physical properties of this titanium oxide are shown in Table 1, and the XPS spectrum is shown in FIG.
[0034]
Next, the photodegradation action on acetaldehyde was evaluated in the same manner as in Example 1. The production rate of carbon dioxide was 43.15 μmol / h per gram of catalyst.
[0035]
Comparative Example 1
β-titanium hydroxide (manufactured by Kishida Chemical) was baked in air at 400 ° C. for 1 hour to obtain titanium oxide. The crystal structure of the obtained titanium oxide was anatase type. The physical properties of this titanium oxide are shown in Table 1, and the XPS spectrum is shown in FIG.
[0036]
Next, the photodegradation action on acetaldehyde was evaluated in the same manner as in Example 1. The production rate of carbon dioxide was 0.93 μmol / h per gram of catalyst.
[0037]
Comparative Example 2
In Example 1, it carried out like Example 1 except having used the photocatalyst body which consists only of a commercially available titanium oxide (made by Degussa, brand name P-25). The production rate of carbon dioxide was 0.0 μmol / h per gram of catalyst. The physical properties of this titanium oxide are shown in Table 1, and the XPS spectrum is shown in FIG.
[0038]
[Table 1]
Example 3
A particulate photocatalyst coating agent was prepared by dispersing the particulate titanium oxide obtained in Example 1 in water. The obtained photocatalyst coating agent was applied to automobile glass and dried to form a titanium oxide layer uniformly on the automobile glass surface.
[0040]
The photocatalyst of the present invention is superior in the oxidative decomposition action (photocatalytic action) of oxidative decomposition with respect to acetaldehyde when irradiated with visible light having a wavelength of 430 nm or more as compared with a commercially available photocatalyst made of only titanium oxide.
[0041]
【The invention's effect】
The titanium oxide of the present invention exhibits a high photocatalytic action when irradiated with visible light having a wavelength of 430 nm or more. The photocatalyst of the present invention (including a photocatalyst comprising only titanium oxide) decomposes various organic substances including aldehydes such as acetaldehyde by the high photocatalytic action of titanium oxide. The photocatalyst coating agent of the present invention makes it easy to apply titanium oxide to building materials, automobile materials, etc., or to coat building materials, automobile materials, etc. with titanium oxide, and is a high photocatalyst for building materials, automobile materials, etc. It is possible to impart an action.
[0042]
In addition, the photocatalyst of the present invention (including a photocatalyst made of only titanium oxide) and a car material coated with a photocatalyst coating agent can decompose NOx in the atmosphere or cause bad odor in living spaces and work spaces. Applicable to decomposing substances (for example, tobacco odor), decomposing organic solvents, pesticides, surfactants, etc. in water, or suppressing the growth of bacteria (for example, radioactive bacteria), algae, mosses, etc. It is.
[Brief description of the drawings]
FIG. 1 is a wavelength-transmittance diagram showing the spectral characteristics of an ultraviolet cut filter attached to a light source during irradiation with visible light for evaluating the photodegradation effect of a photocatalyst in an example.
FIG. 2 is a wavelength-transmittance diagram showing spectral characteristics of an infrared cut filter attached to a light source during irradiation with visible light for evaluating the photodegradation effect of a photocatalyst in an example.
FIG. 3 shows the first and second integrated spectra and the seventh and eighth integrated spectra of titanium oxide used in Example 1 by XPS.
FIG. 4 shows the first and second integrated spectra and the seventh and eighth integrated spectra of titanium oxide used in Example 2 by XPS.
FIG. 5 shows the first and second integrated spectra and the seventh and eighth integrated spectra of titanium oxide used in Comparative Example 1 by XPS.
FIG. 6 shows the first and second integrated spectra and the seventh and eighth integrated spectra of titanium oxide used in Comparative Example 2 by XPS.
Claims (3)
Ｘ1＝Ｂ1／Ａ1 （Ｉ）
により算出される指数Ｘ1が０．９以下であり、かつ、紫外可視拡散反射スペクトルを測定して、波長２５０ｎｍ〜５５０ｎｍの吸光度の積分値をＣ1とし、波長４００ｎｍ〜５５０ｎｍの吸光度の積分値をＤ1としたとき、式（II）
Ｙ1＝Ｄ1／Ｃ1 （II）
により算出される指数Ｙ1が０．１４５以上であることを特徴とする酸化チタン。〔ただし、結合エネルギー４５８ｅＶ〜４６０ｅＶにあるピークの半価幅は、光電子分光測定装置（ピーク位置を決めるための基準には炭素を使用し、Ｘ線源としてＭｇＫα ８ｋＶ ３０ｍＡを使用する。）を用い、酸化チタンについて、チタンの電子状態を１回あたり６０秒で２回分析（１回目、２回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（３回目、４回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（５回目、６回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、チタンの電子状態を１回あたり６０秒で２回分析（７回目、８回目）、酸素の電子状態を１回あたり５６秒で２回分析、炭素の電子状態を１回あたり８０秒で２回分析、を順に行って各々Ｘ線光電子分光スペクトルを求め、ここで前記の一連の分析は、分析時及び分析と分析との間、酸化チタンを大気中に暴露させることなく行い、開始から終了迄の時間が３０分以内となるように行い、その後、チタンの電子状態についての１回目のＸＰＳスペクトルと２回目のＸ線光電子分光スペクトルとを積算して、及び７回目のＸ線光電子分光スペクトルと８回目のＸ線光電子分光スペクトルとを積算して求める。吸光度の積分値は、縦軸を吸光度とし、横軸を波長とした紫外可視拡散反射スペクトルにおいて、指定された波長の範囲内で横軸と拡散反射スペクトルとで囲まれた領域の面積を示す。〕 X-ray photoelectron spectroscopy is used to analyze 8 times, and the integrated spectrum of the first and second analyzes and the integrated spectrum of the seventh and eighth analyzes are obtained for the electronic state of titanium, and the binding energy 458 eV of each integrated spectrum is obtained. the peak in the ~460eV, 1 time and the half width of a peak in the accumulated spectrum of the second analysis and a 1, the half width of a peak in the accumulated spectrum of 7 th and 8 th analysis B 1 The formula (I)
X 1 = B 1 / A 1 (I)
The index X 1 calculated by the above equation is 0.9 or less, and the UV-visible diffuse reflection spectrum is measured, and the integrated value of the absorbance at a wavelength of 250 nm to 550 nm is defined as C 1, and the integrated value of the absorbance at a wavelength of 400 nm to 550 nm Where D 1 is the formula (II)
Y 1 = D 1 / C 1 (II)
Titanium oxide characterized in that the index Y 1 calculated by the above is 0.145 or more. [However, the half width of the peak at a binding energy of 458 eV to 460 eV is obtained by using a photoelectron spectrometer (carbon is used as a reference for determining the peak position, and MgKα 8 kV 30 mA is used as an X-ray source). For titanium oxide, the electronic state of titanium is analyzed twice at 60 seconds per time (first time and second time), the electronic state of oxygen is analyzed twice at 56 seconds per time, and the electronic state of carbon per time Analyzed twice at 80 seconds, analyzed the electronic state of titanium twice at 60 seconds per time (third and fourth times), analyzed the electronic state of oxygen twice at 56 seconds per time, and analyzed the electronic state of carbon as 1 Analyzed twice at 80 seconds per time, analyzed the electronic state of titanium twice at 60 seconds per time (5th and 6th times), analyzed the electronic state of oxygen twice at 56 seconds per time, electronic state of carbon Analyzed twice at 80 seconds per time Analyzing the electronic state of titanium twice at 60 seconds per time (7th and 8th times), analyzing the electronic state of oxygen twice at 56 seconds per time, and analyzing the electronic state of carbon at 80 seconds per time X-ray photoelectron spectroscopy spectra are obtained in order, and the series of analyzes described above is performed without exposing titanium oxide to the atmosphere during and between analyses. Until the time is within 30 minutes, and then the first XPS spectrum and the second X-ray photoelectron spectrum for the electronic state of titanium are integrated, and the seventh X-ray photoelectron spectrum is integrated. And the eighth X-ray photoelectron spectrum are integrated. The integrated value of the absorbance indicates the area of the region surrounded by the horizontal axis and the diffuse reflection spectrum within the specified wavelength range in the UV-visible diffuse reflection spectrum where the vertical axis is the absorbance and the horizontal axis is the wavelength. ]
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000330202A JP4103324B2 (en) | 2000-03-06 | 2000-10-30 | Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000060056 | 2000-03-06 | ||
| JP2000-60056 | 2000-03-06 | ||
| JP2000330202A JP4103324B2 (en) | 2000-03-06 | 2000-10-30 | Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001322816A JP2001322816A (en) | 2001-11-20 |
| JP4103324B2 true JP4103324B2 (en) | 2008-06-18 |
Family
ID=26586819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000330202A Expired - Fee Related JP4103324B2 (en) | 2000-03-06 | 2000-10-30 | Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4103324B2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1418245A (en) * | 2000-11-17 | 2003-05-14 | 有限会社环境设备研究所 | Coating responding to visible light, coating film and article |
| JP4393963B2 (en) | 2004-03-17 | 2010-01-06 | 住友化学株式会社 | Photocatalyst coating liquid |
| JP2010115635A (en) | 2008-06-05 | 2010-05-27 | Sumitomo Chemical Co Ltd | Photocatalyst dispersion, its method of manufacturing the same and application thereof |
| JP2010180303A (en) | 2009-02-04 | 2010-08-19 | Sumitomo Chemical Co Ltd | Hydrophilizing agent, method of producing the same, and use of the same |
| JP2011036770A (en) | 2009-08-07 | 2011-02-24 | Hokkaido Univ | Method for producing noble metal-supported photocatalyst particle |
| JP2011224534A (en) | 2009-09-16 | 2011-11-10 | Sumitomo Chemical Co Ltd | Photocatalyst composite and photocatalyst functional product using the same |
| NL2009015C2 (en) * | 2012-04-10 | 2013-10-15 | Biosparq B V | Method for classification of a sample on the basis of spectral data, method for creating a database and method for using this database, and corresponding computer program, data storage medium and system. |
-
2000
- 2000-10-30 JP JP2000330202A patent/JP4103324B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2001322816A (en) | 2001-11-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100642973B1 (en) | Titanium oxide, photocatalyst comprising same and photocatalytic coating agent | |
| US6730630B2 (en) | Photocatalyst, process for producing the same and photocatalyst coating composition comprising the same | |
| EP1174392B1 (en) | Titanium oxide, and photocatalyst and photocatalyst coating composition using the same | |
| US6830741B1 (en) | Titanium-oxide and photocatalyst and photocatalyst coating composition | |
| US6645460B2 (en) | Titanium hydroxide and photocatalytic coating agent | |
| JP2002126517A (en) | Photocatalyst, method for producing the same, and photocatalytic coating agent containing the same | |
| JP4103324B2 (en) | Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same | |
| JP4048775B2 (en) | Titanium oxide, photocatalyst body and photocatalyst body coating agent using the same | |
| JP4265685B2 (en) | Photocatalyst body, method for producing the same, and photocatalyst body coating agent using the same | |
| JP3981757B2 (en) | Photocatalyst body and photocatalyst body coating agent using the same | |
| JP3959226B2 (en) | Photocatalyst body and photocatalyst body coating agent | |
| JP2002029749A (en) | Titanium dioxide, photocatalytic body using the same and photocatalytic body coating agent | |
| JP2003300729A (en) | Titanium oxide | |
| JP2002143691A (en) | Photocatalyst, method for manufacturing the same and photocatalyst coating agent prepared from the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20041006 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20070720 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070731 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20071001 |
|
| RD05 | Notification of revocation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7425 Effective date: 20080128 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20080304 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20080317 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110404 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120404 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130404 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130404 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140404 Year of fee payment: 6 |
|
| LAPS | Cancellation because of no payment of annual fees |