Silicon carbide (SiC)-loaded graphene photocatalyst for hydrogen production under visible light irradiation and preparation thereof

Patent metadata

Field	Value
Publication number	US-11969716-B2
Application number	US-202318339190-A
Country	US
Kind code	B2
Filing date	Jun 21, 2023
Priority date	Jun 23, 2022
Publication date	Apr 30, 2024
Grant date	Apr 30, 2024

Abstract

This application discloses a silicon carbide (SiC)-loaded graphene photocatalyst for hydrogen production under visible light irradiation and a preparation method thereof. Pure SiC and pure black carbon are respectively prepared and mixed to obtain a mixture with a resistance less than 100Ω. Then the mixture was vacuumized and processed with a current pulse with an increasing voltage until a breakdown occurs, and subjected to ultrasonic stirring, centrifugal washing and vacuum drying in turn to obtain the SiC-loaded graphene photocatalyst. By means of the current pulse, a heterojunction is formed between SiC and graphene to improve the catalytic activity of the photocatalyst; and the photocatalytic hydrogen production rate of SiC nanoparticles can be enhanced after loaded on the graphene.

First claim

What is claimed is:

1. A method for preparing a silicon carbide (SiC)-loaded graphene photocatalyst for hydrogen production under visible light irradiation, comprising:
step (A) preparing a pure SiC;
step (B) preparing a pure black carbon;
step (C) mixing the pure SiC and the pure black carbon to obtain a mixture, wherein the mixture has a resistance less than 100 Ω;
step (D) feeding the mixture to a current pulse processing equipment; and vacuumizing the current pulse processing equipment, and processing the mixture with a current pulse with an increasing voltage until a breakdown of the mixture occurs, wherein the current pulse has a capacitance of 70-80 mF and a voltage of 120-180 V; and
step (E) subjecting the mixture to ultrasonic stirring, centrifugal washing and vacuum drying in turn to obtain the SiC-loaded graphene photocatalyst.

2. The method of claim 1 , wherein step (A) comprises:
step (A1) calcining SiC powder followed by natural cooling to room temperature;
step (A2) immersing the SiC powder obtained in step (A1) with a HF (Hydrogen Fluoride) solution under a sealed and light-proof condition; and
step (A3) filtering an immersion system obtained in step (A2) to collect a filter residue; and subjecting the filter residue to washing with deionized water and vacuum drying to obtain the pure SiC.

3. The method of claim 2 , wherein in step (A1), the SiC powder is calcined at 600-900° C. for 3-4 h;
in step (A2), the HF solution has a HF content of 1-5% by weight; and
in step (A3), the vacuum drying is performed at 50-90° C. for 3-4 h.

4. The method of claim 1 , wherein step (B) comprises:
calcining black carbon powder followed by natural cooling to room temperature to obtain the pure black carbon.

5. The method of claim 4 , wherein the black carbon powder is calcined at 200-300° C. for 3-4 h.

6. The method of claim 1 , wherein in step (E), the ultrasonic stirring is performed at 40-60° C. for 20-60 min.

7. The method of claim 1 , wherein in step (E), the centrifugal washing is performed at 500-800 r/min for 30-40 min.

8. The method of claim 1 , wherein in step (E), the vacuum drying is performed at 60-80° C. for 3-4 h.

9. A SiC-loaded graphene photocatalyst prepared by the method of claim 1 for hydrogen production under visible light irradiation.

Assignees

• Univ Guangdong Technology

Inventors

• Chen Yun
• Lai Shengbao
• Li Biao
• Liu Zuohui
• Wen Guanhai
• Hou Maoxiang
• Chen Xin

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J27/224 Primary

  Silicon carbide · CPC title

• B01J6/001

  Calcining · CPC title

• B01J21/18

  Carbon · CPC title