JPH0234891B2 - - Google Patents
Info
- Publication number
- JPH0234891B2 JPH0234891B2 JP61254361A JP25436186A JPH0234891B2 JP H0234891 B2 JPH0234891 B2 JP H0234891B2 JP 61254361 A JP61254361 A JP 61254361A JP 25436186 A JP25436186 A JP 25436186A JP H0234891 B2 JPH0234891 B2 JP H0234891B2
- Authority
- JP
- Japan
- Prior art keywords
- niobium
- powder
- present
- light
- sulfide
- 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 - Lifetime
Links
- 150000002822 niobium compounds Chemical class 0.000 claims description 8
- 230000001699 photocatalysis Effects 0.000 claims description 7
- 230000003647 oxidation Effects 0.000 claims description 5
- 238000007254 oxidation reaction Methods 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 4
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 3
- 238000005987 sulfurization reaction Methods 0.000 claims description 3
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 2
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 2
- 239000010955 niobium Substances 0.000 claims description 2
- 229910052758 niobium Inorganic materials 0.000 claims description 2
- 230000001747 exhibiting effect Effects 0.000 claims 1
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 239000000126 substance Substances 0.000 description 11
- 239000000843 powder Substances 0.000 description 9
- 239000003054 catalyst Substances 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 6
- 229910052739 hydrogen Inorganic materials 0.000 description 5
- 239000001257 hydrogen Substances 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 230000031700 light absorption Effects 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 150000003568 thioethers Chemical class 0.000 description 4
- QGJOPFRUJISHPQ-UHFFFAOYSA-N Carbon disulfide Chemical compound S=C=S QGJOPFRUJISHPQ-UHFFFAOYSA-N 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 3
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 239000004570 mortar (masonry) Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- QMMFVYPAHWMCMS-UHFFFAOYSA-N Dimethyl sulfide Chemical compound CSC QMMFVYPAHWMCMS-UHFFFAOYSA-N 0.000 description 2
- QUSNBJAOOMFDIB-UHFFFAOYSA-N Ethylamine Chemical compound CCN QUSNBJAOOMFDIB-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 229910000484 niobium oxide Inorganic materials 0.000 description 2
- URLJKFSTXLNXLG-UHFFFAOYSA-N niobium(5+);oxygen(2-) Chemical class [O-2].[O-2].[O-2].[O-2].[O-2].[Nb+5].[Nb+5] URLJKFSTXLNXLG-UHFFFAOYSA-N 0.000 description 2
- 238000007539 photo-oxidation reaction Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- -1 sulfide ions Chemical class 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- RTBFRGCFXZNCOE-UHFFFAOYSA-N 1-methylsulfonylpiperidin-4-one Chemical compound CS(=O)(=O)N1CCC(=O)CC1 RTBFRGCFXZNCOE-UHFFFAOYSA-N 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 150000001299 aldehydes Chemical class 0.000 description 1
- 229910052977 alkali metal sulfide Inorganic materials 0.000 description 1
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 description 1
- JFCQEDHGNNZCLN-UHFFFAOYSA-N anhydrous glutaric acid Natural products OC(=O)CCCC(O)=O JFCQEDHGNNZCLN-UHFFFAOYSA-N 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- QGJOPFRUJISHPQ-NJFSPNSNSA-N carbon disulfide-14c Chemical compound S=[14C]=S QGJOPFRUJISHPQ-NJFSPNSNSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000002815 nickel Chemical class 0.000 description 1
- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- 150000002832 nitroso derivatives Chemical class 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
- 238000007540 photo-reduction reaction Methods 0.000 description 1
- 239000011941 photocatalyst Substances 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、光触媒活性を有するニオビウム化合
物に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a niobium compound having photocatalytic activity.
ニオビウムの複合酸化物を主体とする触媒を用
いてアルカリ金属の硫化物、あるいはメタノール
水溶液の可視光による光分解を行なう場合光触媒
に要求される性質は主として四つある。その(1)は
可視光を吸収する性質であり、その(2)は硫化物イ
オン等の電子供与性物質から電子を奪う性質、す
なわち光酸化能であり、その(3)は電子供与性物質
から受け取つた電子を電子受容性物質に渡す性
質、すなわち光還元能である。その(4)は前記の(2)
と(3)の過程で生成した被酸化物質と被還元物質が
元の物質に逆戻りする反応、すなわち、再結合反
応を防止する性質である。これら４つの性能がバ
ランスよく機能を果たしてはじめて光触媒活性が
発揮される。これらの性質はニオビウム化合物の
性質に含まれているものである。
When photodecomposing an alkali metal sulfide or an aqueous methanol solution using visible light using a catalyst based on a niobium complex oxide, there are mainly four properties required of the photocatalyst. (1) is the property of absorbing visible light, (2) is the property of taking electrons from electron-donating substances such as sulfide ions, that is, photooxidation ability, and (3) is the property of absorbing electron-donating substances such as sulfide ions. This is the property of transferring electrons received from the substance to an electron-accepting substance, that is, photoreducibility. (4) is the above (2)
It is a property that prevents the reaction in which the oxidized substance and the reduced substance generated in the process of (3) return to the original substance, that is, the recombination reaction. Photocatalytic activity is exhibited only when these four functions function in a well-balanced manner. These properties are included in the properties of niobium compounds.
本発明者等は、ニオビウムの酸化物や硫化物か
らなる光活性触媒において、一般に、酸化物の光
吸収は紫外部に偏つており、これに対して硫化物
の光吸収は可視部にわたつているが、水溶液中で
硫化物は不安定であるという欠点を有している
点、そして硫化物の光吸収能力と酸化物の化学的
安定性の両方を取り入れた複合材料が得られ、か
つそれが可視光領域で安定な光触媒材料として使
用できる点に着目し、鋭意研究を重ねた結果、
SO2 -を触媒粒子内に生成させることを特徴とす
るニオビウム化合物を見出し本発明を完成するに
至つた。
The present inventors discovered that in photoactive catalysts made of niobium oxides and sulfides, the light absorption of oxides is generally concentrated in the ultraviolet region, whereas the light absorption of sulfides is concentrated in the visible region. However, sulfides have the disadvantage of being unstable in aqueous solutions, and composite materials that incorporate both the light absorption ability of sulfides and the chemical stability of oxides can be obtained. Focusing on the fact that it can be used as a photocatalytic material that is stable in the visible light region, as a result of intensive research,
The present inventors have discovered a niobium compound that is characterized by producing SO 2 - within catalyst particles, and have completed the present invention.
すなわち、本発明によれば、ニオビウム元素と
アルカリ土類金属の複合酸化物粒子の表面に
SO2 -を高分散度で形成させたことを特徴とする
光触媒活性を有するニオビウム化合物を提供する
ものである。 That is, according to the present invention, on the surface of composite oxide particles of niobium element and alkaline earth metal,
The present invention provides a niobium compound having photocatalytic activity characterized by the formation of SO 2 - with a high degree of dispersion.
本発明のニオビウム化合物は、アルカリ土類金
属の酸化物とニオビウム酸化物の混合物を焼成し
て両者の複合酸化物を形成させてから、ニツケル
酸化物を加えて再焼成して粒子内にニツケルを散
在させたものを作成する。このニツケル添加過程
を省略しても、しない場合の50％以上の活性は発
現できる。このようにして得た粉末を硫化剤とし
て二硫化炭素、硫化メチル等を含む硫化性ガス雰
囲気中において温度800℃に加熱することによつ
て硫化処理を行なうことができる。このようにし
て生成した部分硫化物を酸素または酸素を含む雰
囲気中において温度600℃程度に加熱することに
より酸化物にしたり、あるいは硫黄を少量含んだ
酸化物に変化させることができる。 The niobium compound of the present invention is produced by firing a mixture of alkaline earth metal oxide and niobium oxide to form a composite oxide of both, and then adding nickel oxide and re-firing to incorporate nickel into the particles. Create a scattering of things. Even if this nickel addition step is omitted, 50% or more of the activity can be achieved than without it. The powder thus obtained can be sulfurized by heating it to a temperature of 800° C. in a sulfurizing gas atmosphere containing carbon disulfide, methyl sulfide, etc. as a sulfurizing agent. By heating the partially sulfide thus produced to a temperature of about 600° C. in oxygen or an atmosphere containing oxygen, it can be converted into an oxide or an oxide containing a small amount of sulfur.
本発明では硫化処理の際には二硫化炭素や硫化
メチルのような弱い硫化剤を用いる。その圧力も
硫化剤分圧として１万分の１〜１万分の２気圧程
度にするのがよく、また酸化処理の際には硫化物
濃度の大きい部分を分断して酸化するために酸素
分圧を１気圧程度にする。この硫化処理と酸化処
理を交互に３サイクル施すことにより、光酸化お
よび光還元機能を兼ね備えた光触媒物質が提供さ
れる。 In the present invention, a weak sulfiding agent such as carbon disulfide or methyl sulfide is used during the sulfiding treatment. It is best to set the pressure to about 1/10,000 to 2/10,000 atm as the sulfurizing agent partial pressure, and during oxidation treatment, the oxygen partial pressure should be adjusted to separate and oxidize areas with a high sulfide concentration. Make the pressure around 1 atm. By performing three cycles of the sulfurization treatment and the oxidation treatment alternately, a photocatalytic material having both photooxidation and photoreduction functions is provided.
本発明のニオビウム化合物はバンドギヤツプの
中間にSO2 -の中間電子帯を作つて光吸収特性を
紫外部より可視部に拡大改良したものであり、半
導体触媒が本来有している光酸化能が十分に発揮
されて高い光触媒能を発揮する。本発明によれ
ば、硫化物やメタノール溶液などのほか、電子供
与性の強い液体（例えばエチルアミン）、又は電
子供与性の強い固体物質（例えばブドウ糖、グル
タルミン酸等）の水溶液に本発明のニオビウム化
合物を接触させた状態で可視光を照射すると、還
元性物質（水素等）と酸化性物質（硫黄、あるい
は上記反応基質が酸化されて生ずるアルデヒド、
ニトロソ化合物等）を製造することができる。
The niobium compound of the present invention has an SO 2 - intermediate electron band in the middle of the band gap to expand and improve its light absorption characteristics from the ultraviolet region to the visible region. It exhibits high photocatalytic ability. According to the present invention, in addition to sulfide and methanol solutions, the niobium compound of the present invention is added to liquids with strong electron donating properties (e.g., ethylamine) or aqueous solutions of solid substances with strong electron donating properties (e.g., glucose, glutaric acid, etc.). When visible light is irradiated with the two in contact with each other, reducing substances (hydrogen, etc.) and oxidizing substances (sulfur, or aldehydes produced by the oxidation of the above reaction substrates,
nitroso compounds, etc.) can be produced.
〔実施例〕
次に本発明を実施例により更に詳細に説明す
る。[Example] Next, the present invention will be explained in more detail with reference to Examples.
実施例 １
Nb2O5粉末とSrCO3粉末を重量比1.8：１の比
で混合して乳鉢で粉砕し、1400℃に７時間加熱し
てSrNb2O6を得た。この粉末を7600分の１気圧
のCS2蒸気中800℃で30分間処理し、次いで１気
圧の酸素中で650℃で30分間処理した。この硫
化・酸化処理を３周期行なつて活性化した
SrNb2O6触媒を得た。次に上記の触媒0.30ｇを10
mlの１：１メタノール水溶液に入れ光波長480nm
−750nmの光を300μアインシユタイン照射した。
その結果エネルギー変換効率7.5％で水素0.27ml
を発生させることができた。また同じく触媒0.30
ｇを10mlの0.24M Na2S水溶液に入れ、光波長
480nm−750nmの光を300μアインシユタイン照射
した。その結果エネルギー変換効率25.8％で水素
0.93mlを発生させることができた。Example 1 Nb 2 O 5 powder and SrCO 3 powder were mixed at a weight ratio of 1.8:1, ground in a mortar, and heated to 1400° C. for 7 hours to obtain SrNb 2 O 6 . The powder was treated in 1/7600 atm of CS 2 vapor at 800°C for 30 minutes and then in 1 atm of oxygen at 650°C for 30 minutes. This sulfurization and oxidation treatment was performed for three cycles to activate the
A SrNb 2 O 6 catalyst was obtained. Next, add 0.30g of the above catalyst to 10
Light wavelength 480nm in 1:1 methanol aqueous solution
-750nm light was irradiated at 300μ einstein.
As a result, 0.27ml of hydrogen with an energy conversion efficiency of 7.5%
was able to occur. Also catalyst 0.30
g into 10 ml of 0.24M Na 2 S aqueous solution, and
Light of 480 nm to 750 nm was irradiated with a 300μ einstein beam. As a result, hydrogen with an energy conversion efficiency of 25.8%
It was possible to generate 0.93ml.
実施例 ２
Nb2O5粉末とSrCO3粉末を重量比0.9：１の比
で混合して乳鉢で粉砕し、1400℃に15時間加熱し
てSr2Nb2O7を得た。この粉末に５重量％相当の
NiOを加え乳鉢で粉砕混合してから1000℃に２時
間加熱してニツケル添加粉末を得た。この粉末を
7600分の１気圧のCS2中800℃で30分間処理、お
よび１気圧のO2中650℃で30分間処理を３周期行
なつて活性化したSr2Nb2O7を得た。次に上記の
触媒0.30ｇを10mlの１：１メタノール水溶液に入
れ光波長480nm−750nmの光を300μアインシユタ
イン照射した。その結果エネルギー変換効率6.5
％で水素0.24mlを発生させることができた。また
同じく触媒0.30ｇを10mlの0.24M Na2S水溶液に
入れ、光波長480nm−750nmの光を300μアインシ
ユタイン照射した。その結果エネルギー変換効率
59.4％で水素2.14mlを発生させることができた。Example 2 Nb 2 O 5 powder and SrCO 3 powder were mixed at a weight ratio of 0.9:1, ground in a mortar, and heated to 1400° C. for 15 hours to obtain Sr 2 Nb 2 O 7 . Add 5% by weight to this powder.
NiO was added, pulverized and mixed in a mortar, and heated to 1000°C for 2 hours to obtain a nickel-added powder. This powder
Activated Sr 2 Nb 2 O 7 was obtained by performing three cycles of treatment at 800° C. for 30 minutes in CS 2 at 1/7600 atm and at 650° C. for 30 minutes in O 2 at 1 atm. Next, 0.30 g of the above catalyst was placed in 10 ml of a 1:1 methanol aqueous solution and irradiated with 300 micrometers of light having a wavelength of 480 nm to 750 nm. The resulting energy conversion efficiency is 6.5
%, it was possible to generate 0.24ml of hydrogen. Similarly, 0.30 g of the catalyst was placed in 10 ml of a 0.24 M Na 2 S aqueous solution, and irradiated with 300 microns of light having a wavelength of 480 nm to 750 nm. The resulting energy conversion efficiency
It was possible to generate 2.14ml of hydrogen at 59.4%.
Claims (1)
を硫化処理および酸化処理を繰り返すことにより
製造されるSO2 -を含有する、可視光により光触
媒作用を発現することを特徴とするニオビウム化
合物。1. A niobium compound containing SO 2 - produced by repeatedly subjecting a composite oxide of niobium and an alkaline earth metal to sulfurization and oxidation treatment, and exhibiting photocatalytic activity in the presence of visible light.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61254361A JPS63107815A (en) | 1986-10-25 | 1986-10-25 | Niobium compound with photocatalytic activity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61254361A JPS63107815A (en) | 1986-10-25 | 1986-10-25 | Niobium compound with photocatalytic activity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63107815A JPS63107815A (en) | 1988-05-12 |
| JPH0234891B2 true JPH0234891B2 (en) | 1990-08-07 |
Family
ID=17263919
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61254361A Granted JPS63107815A (en) | 1986-10-25 | 1986-10-25 | Niobium compound with photocatalytic activity |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63107815A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021149678A1 (en) | 2020-01-21 | 2021-07-29 | 三菱ケミカル株式会社 | Display equipment, vehicle interior and exterior member, illuminating lamp, display sign, and vehicle |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5595813A (en) * | 1992-09-22 | 1997-01-21 | Takenaka Corporation | Architectural material using metal oxide exhibiting photocatalytic activity |
| KR0130515B1 (en) * | 1994-08-30 | 1998-04-03 | 강박광 | New photocatalyst and producing method for the same |
| KR0180606B1 (en) * | 1995-09-18 | 1999-03-20 | 강박광 | Novel photocatalyst, its preparation process and hydrotreating process using it |
| KR100342856B1 (en) | 2000-02-22 | 2002-07-02 | 김충섭 | CdZnMS photocatalyst added with cation for water decomposition and preparation there for and method for producing hydrogen by use of the same |
-
1986
- 1986-10-25 JP JP61254361A patent/JPS63107815A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021149678A1 (en) | 2020-01-21 | 2021-07-29 | 三菱ケミカル株式会社 | Display equipment, vehicle interior and exterior member, illuminating lamp, display sign, and vehicle |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63107815A (en) | 1988-05-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |