Efficient Photocatalytic H2 O2 Production Ability of a Novel Graphitic Carbon Nitride/Carbon Composites under Visible Light

Huagen Liang; Anhu Wang; Ruolin Cheng; Xinlong Tian; Shengyu Jing; Panagiotis Tsiakaras

doi:10.1002/smll.202303813

Efficient Photocatalytic H₂ O₂ Production Ability of a Novel Graphitic Carbon Nitride/Carbon Composites under Visible Light

Small. 2023 Nov;19(48):e2303813. doi: 10.1002/smll.202303813. Epub 2023 Jul 28.

Authors

Huagen Liang^{1

2}, Anhu Wang^{1

2}, Ruolin Cheng¹, Xinlong Tian³, Shengyu Jing^{4

5}, Panagiotis Tsiakaras⁵

Affiliations

¹ Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, Carbon Neutrality Institute, China University of Mining and Technology, Xuzhou, 221008, China.
² School of Materials Science and Physics, China University of Mining and Technology, Xuzhou, 221008, China.
³ State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Lab of Fine Chemistry, School of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China.
⁴ School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221008, China.
⁵ Laboratory of Alternative Energy Conversion Systems, Department of Mechanical Engineering, School of Engineering, University of Thessaly, 1 Sekeri Str., Pedion Areos, 38334, Greece.

PMID: 37507829
DOI: 10.1002/smll.202303813

Abstract

In the present work, using one-step calcination of a mixture made of potassium hydroxide (KOH), melamine, and microplastics, this work prepares a novel graphitic carbon nitride/carbon (g-C₃ N₄ /C) composite, which can be employed to photo-catalytically produce hydrogen peroxide (H₂ O₂ ) at a high rate up to 6.146 mmol g^-1 h^-1 under visible light irradiation. By analyzing the energy band structure of the catalyst, the production of H₂ O₂ in this system consists of two single-electron reactions. The modification of KOH makes abundant N-vacancies caused by cyano-groups in g-C₃ N₄ , enhancing the electron absorption ability. Moreover, the introduction of graphitic carbon increases its specific surface area and porosity and improves the adsorption ability of O₂ . Simultaneously, their synergism reduces the g-C₃ N₄ band gap, making both the conduction-band and valence-band positions more negative, showing enhanced reduction ability, lowering the energy barrier for oxygen reduction, and greatly improving the photogeneration performance of H₂ O₂ .

Keywords: H2O2 production; graphitic carbon nitride; microplastics; photocatalysis; potassium hydroxide (KOH)-doping; stepwise single-electron reactions.

Abstract

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