The enhancement of photocatalytic hydrogen production over Ag₂WO₄ modified g-C₃N₄ with Pt as cocatalyst

ABSTRACT

The construction of heterojunction photocatalyst is an effective mean to improve the photoexcited electron–hole pair separation. The Ag₂WO₄-doped graphitic carbon nitride (g-C₃N₄, C₃N₄ for short) composite photocatalysts were fabricated by a simple calcination and in-situ depositing strategy. The composites were characterized by different techniques. The effects of Ag₂WO₄ content, type of scavengers, pH value of reaction solution and dose of scavenger on photocatalytic hydrogen (H₂) generation were studied. It was found that the Ag₂WO₄ micro-nano particles were highly dispersed on the C₃N₄ surface. After doping Ag₂WO₄, the light absorption range of Ag₂WO₄-C₃N₄ material was broadened effectively from 440 nm to 448 nm, and the BET surface area of C₃N₄ was increased from 35.63 to 40.73 cm²·g⁻¹, indicating that Ag₂WO₄ loading could provide some new BET surface areas. The binding energy of all elements in Ag₂WO₄-4/C₃N₄ was clearly shifted due to the charge transfer from C₃N₄ to Ag₂WO₄, implying a strong interaction between C₃N₄ and Ag₂WO₄. The photocatalytic H₂ production rate of the optimized Ag₂WO₄-4/C₃N₄ was 6047.4 μmol·g⁻¹·h⁻¹, which was 2.04 and 171.8 times that of C₃N₄ and Ag₂WO₄, respectively. While Ag₂WO₄-4/C₃N₄ exhibited a poor H₂ production performance in the absence of Pt co-catalyst (309.3 μmol·g⁻¹·h⁻¹), indicating the formation of heterojunction among Ag₂WO₄, C₃N₄ and Pt.

KEYWORDS:

• Carbon nitride
• Ag₂WO₄
• heterojunction
• photocatalytic H₂ production
• Pt cocatalyst

Acknowledgements

The project was supported by the National Natural Science Foundation of China (51676064), the Program for Science & Technology Innovation Talents in Universities of Henan Province (19HASTIT045), and the Innovative Research Team of Henan Polytechnic University (T2020-3).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15567036.2024.2346161.

Additional information

Notes on contributors

Manman Jing

Manman Jing is a master student at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. Her research focuses on photocatalytic hydrogen production technology. [email protected].

Anchao Zhang

Anchao Zhang is a professor in the School of Mechanical and Power Engineering, Henan Polytechnic University, China. He received his B.S. degree from College of Energy and Environment, Zhongyuan Institute of Technology, China and received his M.S. and Ph.D. degree from School of Energy and Power Engineering, Huazhong University of Science and Technology, China. His areas of interest include clean and efficient utilization of coal, collaborative control technology of various pollutants, photocatalytic hydrogen production technology, and photocatalytic pollution treatment technology. [email protected]

Qianqian Zhang

Qianqian Zhang is awarded PhD in mechanical engineering from Henan Polytechnic University in 2024, and she is working as a lecturer at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. Her research focuses on the treatment of power plant flue gas pollutants, electrocatalytic and photocatalytic hydrogen production technology. [email protected].

Hua Wang

Hua Wang is a professor at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. She is doing research on solar thermal utilization, efficient utilization technology of biomass energy, and high-quality utilization technology of kitchen waste. [email protected].

Tao Lu

Tao Lu is a master student at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. His research focuses on photocatalytic hydrogen production technology. [email protected].

Feixiang Ni

Feixiang Ni is a master student at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. His research focuses on photocatalytic hydrogen production technology. [email protected].

Min Li

Min Li is a master student at the School of Mechanical and Power Engineering, Henan Polytechnic University from 2022. Her research focuses on photocatalytic hydrogen production technology. [email protected].

Haixing Du

Haixing Du studied as a master student at the School of Mechanical and Power Engineering, Henan Polytechnic University from 2022. His research focuses on photoelectrocatalysis and pollutant control technology. [email protected].

Xinmin Zhang

Xinmin Zhang is a professor at the School of Mechanical and Power Engineering, Henan Polytechnic University, China. He is doing research on micro/nano manufacturing, biomass heat utilization technology, and low-grade waste heat/energy utilization technology. [email protected].