Catalyst for photo-catalytically decomposing water to produce hydrogen and preparation method of catalyst

Abstract

The invention relates to a catalyst for photo-catalytically decomposing water to produce hydrogen and a preparation method of the catalyst. The catalyst CdS / UiO-66 or CdS / UiO-66(NH2) is formed by compounding UiO-66 or UiO-66(NH2) and CdS in the mass ratio of 100: (1-100). The invention further provides the preparation method of the catalyst. The invention further provides a method for photo-catalytically decomposing water to produce hydrogen by the catalyst. The photo-catalyst formed by compounding the CdS / UiO-66 and the CdS / UiO-66(NH2) in situ have a high hydrogen production rate; compared with that of pure CdS, the hydrogen production rate of the compound photo-catalyst is obviously improved.

Description

technical field

[0001] The invention relates to a catalyst for producing hydrogen by photocatalytically decomposing water and a preparation method thereof, and also relates to a method for producing hydrogen by photocatalytically decomposing water, belonging to the technical field of photocatalysis. Background technique

[0002] At present, fossil energy is gradually being exhausted, and the pollution generated during its utilization will bring serious environmental problems. Considering environmental issues from the perspective of energy, using clean and renewable solar photocatalytic water splitting to produce hydrogen energy that is easy to use is an ideal way to solve energy problems. The key to this method.

[0003] In recent years, the preparation of hydrogen based on semiconductor photocatalysts and semiconductor composite materials has attracted extensive attention. CdS is an n-type semiconductor with a bandwidth of 2.4eV, which has the properties of visible light ...

Examples

Embodiment 1

[0053] This example provides four photocatalytic water splitting catalysts CdS / UiO-66 for hydrogen production, which are prepared by the following steps:

[0054] Weigh 0.0032g, 0.0064g, 0.0128g, 0.0256g of activated UiO-66 respectively, add them to 24mL of dimethyl sulfoxide solvent, stir in a water bath at 25°C for 30 minutes, then weigh 0.064g Four parts of cadmium acetate were added to the above dimethyl sulfoxide solutions with different UiO-66 contents, and the stirring was continued for 3 hours, then transferred to a 30mL autoclave containing a polytetrafluoroethylene liner, and heated at 180 ℃ oven at constant temperature for 12 hours, naturally cooled to room temperature, washed several times with ethanol, and then put the product into a high-pressure reactor filled with 24mL ethanol at 80°C for 12 hours, and finally centrifuged the product at 100°C After drying for 12 hours, the mass ratios of precursor UiO-66 to cadmium acetate were 5:100, 10:100, 20:100 and 40:100,...

Embodiment 2

[0057] This example provides four kinds of catalysts CdS / UiO-66(NH 2 ), which was prepared by the following steps:

[0058] UiO-66 in embodiment 1 is changed into UiO-66 (NH 2 ), other conditions are the same as in Example 1, and the precursor UiO-66 (NH 2 ) to cadmium acetate with mass ratios of 5:100, 10:100, 20:100 and 40:100, respectively, the photocatalytic water splitting catalyst CdS / UiO-66(NH 2 ).

[0059] The XRD patterns of these four photocatalytic water splitting catalysts for hydrogen production are as follows: Figure 4 shown by Figure 4 It can be seen that UiO-66(NH 2 ) diffraction peaks, indicating that the above-mentioned photocatalytic water splitting catalyst for hydrogen production contains UiO-66(NH 2 ) phase, and the diffraction peak of CdS appeared at a high angle, indicating that CdS exists in the above-mentioned photocatalytic water splitting catalyst for hydrogen production.

Embodiment 3

[0060] Example 3 Photocatalytic water splitting activity evaluation

[0061] Using the Labsolar-II instrument of Profil Company to carry out the evaluation experiment of photocatalytic decomposition of water and Mars on the catalyst, the evaluation experiment is carried out in the following way:

[0062] Weigh 0.01g of catalyst and dissolve it in a beaker containing 100mL of distilled water, then weigh 4.50g of sodium sulfide and 2.50g of sodium sulfite as sacrificial reagents and dissolve in it, then place the beaker on a magnetic stirrer to stir for dispersion, and finally put it into an ultrasonic instrument , sonicate for 20 minutes under the condition of 90Hz;

[0063] After the ultrasonic treatment is completed, the reactants in the beaker are transferred to the quartz reactor of the photocatalytic device, and the entire photocatalytic device is vacuumed before the reaction starts, which needs to reach minus one atmospheric pressure;

[0064] The xenon light source is u...

technical field

[0001] The invention relates to a catalyst for producing hydrogen by photocatalytically decomposing water and a preparation method thereof, and also relates to a method for producing hydrogen by photocatalytically decomposing water, belonging to the technical field of photocatalysis. Background technique

[0002] At present, fossil energy is gradually being exhausted, and the pollution generated during its utilization will bring serious environmental problems. Considering environmental issues from the perspective of energy, using clean and renewable solar photocatalytic water splitting to produce hydrogen energy that is easy to use is an ideal way to solve energy problems. The key to this method.

[0003] In recent years, the preparation of hydrogen based on semiconductor photocatalysts and semiconductor composite materials has attracted extensive attention. CdS is an n-type semiconductor with a bandwidth of 2.4eV, which has the properties of visible light ...

Examples

Embodiment 1

[0053] This example provides four photocatalytic water splitting catalysts CdS / UiO-66 for hydrogen production, which are prepared by the following steps:

[0054] Weigh 0.0032g, 0.0064g, 0.0128g, 0.0256g of activated UiO-66 respectively, add them to 24mL of dimethyl sulfoxide solvent, stir in a water bath at 25°C for 30 minutes, then weigh 0.064g Four parts of cadmium acetate were added to the above dimethyl sulfoxide solutions with different UiO-66 contents, and the stirring was continued for 3 hours, then transferred to a 30mL autoclave containing a polytetrafluoroethylene liner, and heated at 180 ℃ oven at constant temperature for 12 hours, naturally cooled to room temperature, washed several times with ethanol, and then put the product into a high-pressure reactor filled with 24mL ethanol at 80°C for 12 hours, and finally centrifuged the product at 100°C After drying for 12 hours, the mass ratios of precursor UiO-66 to cadmium acetate were 5:100, 10:100, 20:100 and 40:100,...

Embodiment 2

[0057] This example provides four kinds of catalysts CdS / UiO-66(NH 2 ), which was prepared by the following steps:

[0058] UiO-66 in embodiment 1 is changed into UiO-66 (NH 2 ), other conditions are the same as in Example 1, and the precursor UiO-66 (NH 2 ) to cadmium acetate with mass ratios of 5:100, 10:100, 20:100 and 40:100, respectively, the photocatalytic water splitting catalyst CdS / UiO-66(NH 2 ).

[0059] The XRD patterns of these four photocatalytic water splitting catalysts for hydrogen production are as follows: Figure 4 shown by Figure 4 It can be seen that UiO-66(NH 2 ) diffraction peaks, indicating that the above-mentioned photocatalytic water splitting catalyst for hydrogen production contains UiO-66(NH 2 ) phase, and the diffraction peak of CdS appeared at a high angle, indicating that CdS exists in the above-mentioned photocatalytic water splitting catalyst for hydrogen production.

Embodiment 3

[0060] Example 3 Photocatalytic water splitting activity evaluation

[0061] Using the Labsolar-II instrument of Profil Company to carry out the evaluation experiment of photocatalytic decomposition of water and Mars on the catalyst, the evaluation experiment is carried out in the following way:

[0062] Weigh 0.01g of catalyst and dissolve it in a beaker containing 100mL of distilled water, then weigh 4.50g of sodium sulfide and 2.50g of sodium sulfite as sacrificial reagents and dissolve in it, then place the beaker on a magnetic stirrer to stir for dispersion, and finally put it into an ultrasonic instrument , sonicate for 20 minutes under the condition of 90Hz;

[0063] After the ultrasonic treatment is completed, the reactants in the beaker are transferred to the quartz reactor of the photocatalytic device, and the entire photocatalytic device is vacuumed before the reaction starts, which needs to reach minus one atmospheric pressure;

[0064] The xenon light source is u...

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