CN103055900A - Pt/CdS composite visible-light-induced photocatalyst and preparation method thereof - Google Patents
Pt/CdS composite visible-light-induced photocatalyst and preparation method thereof Download PDFInfo
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- CN103055900A CN103055900A CN2013100305679A CN201310030567A CN103055900A CN 103055900 A CN103055900 A CN 103055900A CN 2013100305679 A CN2013100305679 A CN 2013100305679A CN 201310030567 A CN201310030567 A CN 201310030567A CN 103055900 A CN103055900 A CN 103055900A
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
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Abstract
The invention discloses a Pt/CdS composite visible-light-induced photocatalyst and a preparation method thereof. The Pt/CdS composite visible-light-induced photocatalyst is prepared by loading cocatalyst platinum nanoparticles on cadmium sulfide, and the loading quantity is calculated according to a weight ratio, namely, the ratio of the cocatalyst platinum nanoparticles to the cadmium sulfide is preferably 0.5:100. The preparation method comprises the steps of: firstly, preparing the cocatalyst platinum nanoparticles with specific features, then stirring the prepared cocatalyst platinum nanoparticles with the special features for 2h by using an impregnation method and loading the cocatalyst platinum nanoparticles on the cadmium sulfide, filtering, washing and drying an obtained turbid liquid, and finally obtaining the Pt/CdS composite visible-light-induced photocatalyst. The Pt/CdS composite visible-light-induced photocatalyst disclosed by the invention has higher reaction activity of preparing hydrogen by splitting water through photocatalysis. The preparation method is simple and easy to operate and is convenient in large-scale production.
Description
Technical field
The present invention relates to a kind of Pt/CdS composite visible light catalyst and preparation method thereof, belong to solar energy and utilize the photolysis water hydrogen technology.
Technical background
Photocatalysis technology is easy to operate, pollution-free with it, can directly utilize the advantage such as sunshine to become one of study hotspot that current solar energy utilizes.
Co-catalyst plays very important effect in the photocatalytic hydrogen production by water decomposition reaction system.Photochemical catalyst self usually only has lower or does not have hydrogen production by water decomposition active at all, only has after the load cocatalyst, and it is active that photochemical catalyst just shows higher photocatalytic hydrogen production by water decomposition.Pt has good catalytic activity, changes the crystal morphology of co-catalyst, affects co-catalyst to the adsorption ability of hydrogen ion or hydrone, will bring tremendous influence to the photocatalytic activity of hydrogen production by water decomposition reaction system.
The present invention is based on the synthetic raising to photocatalytic activity of pattern control of noble metal nano particles, develop a kind of Pt/CdS visible light composite photo-catalyst, improve the photocatalysis performance of photodissociation aqueous systems.
Summary of the invention
One of purpose of the present invention provides a kind of Pt/CdS composite visible light catalyst.
Two of purpose of the present invention provides the preparation method of above-mentioned a kind of Pt/CdS composite visible light catalyst, and the equipment that this preparation method is simple, do not need complex and expensive, synthesis condition is gentle, be convenient to large-scale production.
Technical scheme of the present invention
A kind of Pt/CdS composite visible light catalyst is about to the co-catalyst Pt nanoparticle and loads on the cadmium sulfide and form, and load capacity is by weight calculating, i.e. the co-catalyst Pt nanoparticle: cadmium sulfide is 0.5:100;
The pattern of described co-catalyst Pt nanoparticle is preferably positive cuboctahedron.
The preparation method of above-mentioned a kind of Pt/CdS composite visible light catalyst specifically comprises the steps:
(1), the preparation of co-catalyst Pt nanoparticle;
With K
2PtCl
4Solid is dissolved in the deionized water, obtains K
2PtCl
4Solution;
With C
14TABr puts into deionized water, and ultrasonic dissolution obtains C
14TABr solution;
K with above-mentioned gained
2PtCl
4Solution and C
14Put into 50 ℃ water-bath after both mixing of TABr solution after the solution clarification, adding sodium borohydride continuation control temperature is 50 ℃ and carries out reduction reaction 6h, obtains the co-catalyst Pt nanoparticle;
The K that above-mentioned reaction is used
2PtCl
4Solution, C
14The amount of TABr solution and sodium borohydride is calculated in molar ratio, i.e. K
2PtCl
4: C
14TABr: sodium borohydride is 1:1:45;
(2), the co-catalyst Pt nanoparticle of step (1) gained stirred 2h by infusion process load on the cadmium sulfide, with the suspension that obtains filter, washing, oven dry, finally obtain the Pt/CdS composite photo-catalyst.
Beneficial effect of the present invention
A kind of Pt/CdS composite visible light catalyst of the present invention, has specific pattern owing to utilize, particularly the co-catalyst Pt of positive cuboctahedron special appearance loads on the surface of photochemical catalyst CdS, thereby realized the modifying surface to photochemical catalyst CdS, and significantly improved the reactivity of cadmium sulfide photochemical catalyst photocatalytic hydrogen production by water decomposition.
Further, simple, the equipment that do not need complex and expensive of the preparation method of a kind of Pt/CdS composite visible light catalyst of the present invention, synthesis condition gentle, be convenient to large-scale production.
Description of drawings :
Fig. 1 a, embodiment 1 gained have the just TEM of cube octahedral co-catalyst Pt;
The HRTEM figure with cube octahedral co-catalyst Pt just of Fig. 1 b, embodiment 1 gained;
The power spectrum EDS figure with cube octahedral co-catalyst Pt just of Fig. 1 c, embodiment 1 gained;
The TEM figure of a kind of Pt/CdS composite visible light catalyst of Fig. 2 a, embodiment 1 gained;
The HRTEM figure of a kind of Pt/CdS composite visible light catalyst of Fig. 2 b, embodiment 1 gained;
The power spectrum EDS figure of a kind of Pt/CdS composite visible light catalyst of Fig. 2 c, embodiment 1 gained;
A kind of Pt/CdS composite visible light catalyst of Fig. 3, comparative examples and embodiment 1 gained utilizes the active situation of visible light (wavelength is greater than 420nm) hydrogen production by water decomposition, curve a is the situation of the Pt/CdS composite visible light catalyst photocatalytic hydrogen production by water decomposition of the common metal platinum load cadmium sulfide gained that does not carry out pattern control of comparative examples, and curve b is that embodiment 1 has the just situation of the Pt/CdS composite visible light catalyst photocatalytic hydrogen production by water decomposition of the cadmium sulfide gained of the co-catalyst platinum load of cube shape of octahedron.
The specific embodiment
Also by reference to the accompanying drawings the present invention is further set forth below by specific embodiment, but do not limit the present invention.
Embodiment 1
A kind of Pt/CdS composite visible light catalyst, being about to have cube octahedral co-catalyst Pt nanoparticle just loads on the cadmium sulfide and forms, load capacity is by weight calculating, and namely have just cube octahedral co-catalyst Pt nanoparticle: cadmium sulfide is 0.5:100.
The preparation method of above-mentioned a kind of Pt/CdS composite visible light catalyst specifically comprises the steps:
(1), the just preparation of the Pt nanoparticle of cube shape of octahedron
Getting 0.01245g is 1mM K
2PtCl
4Solid is dissolved in the 10ml deionized water, obtains K
2PtCl
4Solution;
Getting 1.009g is the C of 100mM
14TABr is dissolved in the 10ml deionized water, and ultrasonic 10min obtains C
14TABr solution;
K with above-mentioned gained
2PtCl
4Solution and C
14After mixing, puts into TABr solution 50 ℃ water-bath after the solution clarification, adding 0.03405g is the 45mM sodium borohydride, reaction vessel is airtight, carries out catalytic reduction reaction 6h under 50 ℃ of water bath condition, namely gets to have the just co-catalyst Pt nanoparticle of cube shape of octahedron;
TEM, the HRTEM figure with co-catalyst Pt nanoparticle of cube shape of octahedron just of above-mentioned gained and power spectrum EDS figure are such as Fig. 1 a, Fig. 1 b, Fig. 1 c.Can find out from the TEM figure of Fig. 1 a, the co-catalyst Pt nanoparticle of preparation gained has just cube octahedral structure, can draw spacing of lattice from the HRTEM figure of Fig. 1 b is 2.28, table look-up to such an extent that this particle is grown along<111〉direction, the gained nano particle is positive cuboctahedron, just has from the power spectrum EDS of Fig. 1 c figure is prepared as can be known that a cube octahedral co-catalyst Pt nanoparticle is pure phase.
(2), the preparation of Pt/CdS composite visible light catalyst
Taking by weighing 1.09g is the cadmium sulfide solid, be dissolved in the 100ml deionized water, stir a moment, just have with what step (1) had prepared that a cube octahedral co-catalyst Pt nanoparticle joins in the cadmium sulfide solution, make and just have that the mass fraction of cube octahedral co-catalyst Pt nanoparticle is 0.5wt%, stir 2h, suspension is filtered, behind absolute ethanol washing, the control temperature is 60 ℃ dries, and obtains the Yellow nanometer particle and is (0.5wt%) Pt/CdS composite visible light catalyst.
TEM, the HRTEM figure of the Pt/CdS composite visible light catalyst nano particle of above-mentioned gained and power spectrum EDS figure are such as Fig. 2 a, Fig. 2 b, Fig. 2 c.Can find out from the TEM figure of Fig. 2 a, the success of co-catalyst Pt nanoparticle loaded to cadmium sulfide surface, and be evenly distributed, can find out that from Fig. 2 b the Pt nanoparticle that loads on the cadmium sulfide has kept original specifically cube shape of octahedron just, scheme to contain sulphur, cadmium and platinum element in the Pt/CdS composite catalyst as can be known from the EDS of Fig. 2 c.
Comparative examples 1
A kind of Pt/CdS composite visible light catalyst is about to metal platinum and loads on the cadmium sulfide and form, and load capacity is by weight calculating, i.e. metal platinum: cadmium sulfide is 0.5:100.
The preparation method of above-mentioned a kind of Pt/CdS composite visible light catalyst specifically comprises the steps:
Taking by weighing 1.09g is the cadmium sulfide solid, be dissolved in the 100ml deionized water, stir a moment, metal platinum is joined in the cadmium sulfide solution, the mass fraction that makes platinum is 0.5wt%, stir 2h, control temperature behind the suspension filtration washing is 60 ℃ dries, obtain yellow (0.5wt%) Pt/CdS composite visible light catalyst.
Use
Embodiment
The application of Pt/CdS composite visible light catalyst in hydrogen production by water decomposition with embodiment 1 and comparative examples gained
Take by weighing 2 parts of 16.77g (NH
4)
2SO
3, be dissolved in respectively in the 100mL deionized water, treat (NH
4)
2SO
3H
2After O dissolves fully, the a 0.05g(0.5wt% that adds embodiment 1 gained) Pt/CdS composite visible light catalyst, the a 0.05g(0.5wt% that adds the comparative examples gained) Pt/CdS composite visible light catalyst, stir respectively 5min, reactor is connected with the photolysis water hydrogen reaction system, intrasystem air is pumped.Light source utilizes 300W Xe lamp, and (420nm<λ<800nm) utilizes the high water layer of 10cm to filter infrared ray in the light source, prevents that reacting liquid temperature from raising, and makes the light degradation reaction temperature be stabilized in room temperature state as visible light to use optical filter to make incident light.In the atmosphere of nitrogen, survey its photocatalysis performance with gas chromatograph (GC7890 II, Shanghai Techcomp Instrument Ltd.) every certain hour.
The active situation of above-mentioned photocatalytic hydrogen production by water decomposition as shown in Figure 3, curve a represents in the comparative examples that photoreduction met hod routinely loads on platinum the Pt/CdS composite visible light catalyst photocatalytic hydrogen production by water decomposition of the upper preparation of CdS among Fig. 3; Curve b represents the active situation that cube Pt nanoparticle of octahedral pattern loads to the Pt/CdS composite visible light catalyst photocatalytic hydrogen production by water decomposition of gained on the cadmium sulfide that has of embodiment 1 gained, as can be seen from Figure 3, the catalytic activity of co-catalyst platinum being carried out the Pt/CdS composite visible light catalyst of the rear gained of pattern control is significantly improved, and shows that the synthetic Pt/CdS composite visible light catalyst of pattern control has efficient visible light photocatalysis performance.
Foregoing only is the basic explanation of the present invention under conceiving, and according to any equivalent transformation that technical scheme of the present invention is done, all should belong to protection scope of the present invention.
Claims (5)
1. a Pt/CdS composite visible light catalyst is characterized in that described Pt/CdS composite visible light catalyst, is about to the co-catalyst Pt nanoparticle and loads on the cadmium sulfide and form.
2. a kind of Pt/CdS composite visible light catalyst as claimed in claim 1, it is characterized in that described Pt/CdS composite visible light catalyst, by weight calculating, i.e. co-catalyst Pt nanoparticle: cadmium sulfide is that the ratio of 0.5:100 loads to the co-catalyst Pt nanoparticle and forms on the cadmium sulfide.
3. a kind of Pt/CdS composite visible light catalyst as claimed in claim 2, the pattern that it is characterized in that described co-catalyst Pt nanoparticle is positive cuboctahedron.
4. such as the preparation method of claim 1,2 or 3 described a kind of Pt/CdS composite visible light catalysts, it is characterized in that specifically comprising the steps:
(1), the preparation of co-catalyst Pt nanoparticle;
With K
2PtCl
4Solid is dissolved in the deionized water, obtains K
2PtCl
4Solution;
With C
14TABr puts into deionized water, and ultrasonic dissolution obtains C
14TABr solution;
K with above-mentioned gained
2PtCl
4Solution and C
14Put into 50 ℃ water-bath after both mixing of TABr solution after the solution clarification, adding sodium borohydride continuation control temperature is 50 ℃ and carries out reduction reaction 6h, obtains the co-catalyst Pt nanoparticle;
(2), the co-catalyst Pt nanoparticle of step (1) gained stirred 2h by infusion process load on the cadmium sulfide, with the suspension that obtains filter, washing, oven dry, finally obtain the Pt/CdS composite visible light catalyst.
5. the preparation method of a kind of Pt/CdS composite visible light catalyst as claimed in claim 4 is characterized in that used K in the reduction reaction described in the step (1)
2PtCl
4Solution, C
14The amount of TABr solution and sodium borohydride, calculating in molar ratio is K
2PtCl
4: C
14TABr: sodium borohydride is 1:1:45.
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103316693A (en) * | 2013-07-03 | 2013-09-25 | 西北师范大学 | Photocatalyst Cd/CdS containing catalyst promoter Cd as well as preparation method and application of photocatalyst Cd/CdS in photocatalysis hydrogen production reaction |
CN103331174A (en) * | 2013-07-02 | 2013-10-02 | 上海电力学院 | Palladium-loaded cadmium sulfide visible-light-induced photocatalyst and preparation method thereof |
CN104923264A (en) * | 2015-05-28 | 2015-09-23 | 淮北师范大学 | Preparation method and application of precious metal-modified CdS nanorod photocatalyst |
CN104998663A (en) * | 2015-08-10 | 2015-10-28 | 福州大学 | Compound photocatalyst CdS-Pt@CeO2 and preparing method and application thereof |
CN107126964A (en) * | 2017-04-24 | 2017-09-05 | 湖南大学 | A kind of preparation method of regular octahedron cadmium sulfide and application |
CN109331843A (en) * | 2018-10-24 | 2019-02-15 | 温州大学 | Graininess multicomponent sulfide-platinum heterojunction photocatalysis composite material and preparation method thereof and its production hydrogen application |
CN113368874A (en) * | 2021-05-26 | 2021-09-10 | 福建技术师范学院 | Up-conversion photocatalyst and preparation method and application thereof |
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CN102189267A (en) * | 2011-04-26 | 2011-09-21 | 浙江理工大学 | Method for preparing highly-dispersed regular octahedral platinum nano particles |
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Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103331174A (en) * | 2013-07-02 | 2013-10-02 | 上海电力学院 | Palladium-loaded cadmium sulfide visible-light-induced photocatalyst and preparation method thereof |
CN103316693A (en) * | 2013-07-03 | 2013-09-25 | 西北师范大学 | Photocatalyst Cd/CdS containing catalyst promoter Cd as well as preparation method and application of photocatalyst Cd/CdS in photocatalysis hydrogen production reaction |
CN104923264A (en) * | 2015-05-28 | 2015-09-23 | 淮北师范大学 | Preparation method and application of precious metal-modified CdS nanorod photocatalyst |
CN104923264B (en) * | 2015-05-28 | 2017-05-10 | 淮北师范大学 | Preparation method and application of precious metal-modified CdS nanorod photocatalyst |
CN104998663A (en) * | 2015-08-10 | 2015-10-28 | 福州大学 | Compound photocatalyst CdS-Pt@CeO2 and preparing method and application thereof |
CN104998663B (en) * | 2015-08-10 | 2017-06-06 | 福州大学 | A kind of composite photo-catalyst CdS Pt@CeO2And its preparation method and application |
CN107126964A (en) * | 2017-04-24 | 2017-09-05 | 湖南大学 | A kind of preparation method of regular octahedron cadmium sulfide and application |
CN107126964B (en) * | 2017-04-24 | 2019-11-08 | 湖南大学 | A kind of preparation method and application of regular octahedron cadmium sulfide |
CN109331843A (en) * | 2018-10-24 | 2019-02-15 | 温州大学 | Graininess multicomponent sulfide-platinum heterojunction photocatalysis composite material and preparation method thereof and its production hydrogen application |
CN113368874A (en) * | 2021-05-26 | 2021-09-10 | 福建技术师范学院 | Up-conversion photocatalyst and preparation method and application thereof |
CN113368874B (en) * | 2021-05-26 | 2023-02-10 | 福建技术师范学院 | Up-conversion photocatalyst and preparation method and application thereof |
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Application publication date: 20130424 |