Progress on g-C3N4 based heterojunction photocatalyst for H2 production via Photocatalytic water splitting

• Published in: Journal of alloys and compounds Vol. 1002; p. 175062
• Main Authors: Shuaibu, Abubakar Saidu, Hafeez, Hafeez Yusuf, Mohammed, J., Dankawu, U.M., Ndikilar, Chifu E., Suleiman, Abdussalam Balarabe
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2024
• Subjects: Graphitic carbon nitride; Hydrogen generation; Photocatalyst; Solar fuel; Water splitting; Water splitting; Hydrogen generation; Photocatalyst; Solar fuel; Graphitic carbon nitride
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2024.175062

The semiconductor polymeric photocatalyst known as g-C3N4 possesses an acceptable energy band gap (∼2.7 eV), excellent structure, low toxicity, chemical stability, high thermal resistance, cost-effectiveness, easy synthesis, and the ability to absorb light. This makes it a viable choice for utilization as a photocatalyst in the visible light spectrum. However, despite all these excellent properties, g-C3N4 has some alarming drawbacks that limit its performance for photocatalytic H2 generation via photocatalytic water splitting, these drawbacks include massive recombination of charge carriers, limited visible light absorption, and low surface area. Herein, this review focuses on recent progress made on g-C3N4-based heterojunction photocatalyst for H2 production via PC water splitting. The review also goes further to discuss the recent synthesis method, the origin of g-C3N4, the importance of H2 as a fuel, properties and ways of modifying g-C3N4 such as elemental doping (metal and non-metal) and heterojunction engineering (type I, type II, Z-scheme, and S-scheme). Various challenges connected with g-C3N4 and hindering its overall performance were also identified and extensively discussed. Additionally, the fabrication approach for g-C3N4 and the properties of g-C3N4 were reviewed. Most importantly, the solar H2 production achieved in the study of the g-C3N4 material as the main photocatalyst have been exclusively reviewed and discussed. Based on the findings of this review article, g-C3N4/Bi4Ti3O12/Bi4O5I2 is the photocatalyst with the highest hydrogen evolution rate of 56,600 μmolh−1g−1. The photocatalyst was synthesized using hydrothermal method of fabrication with triethanolamine (TEOA) as the sacrificial agent. Hence, this review will inspire future researchers to expand the utilization of g-C3N4-based materials for PC water splitting. [Display omitted] •Origin of g-C3N4 was review and explained.•Synthesis method of g-C3N4 based material was reviewed and discussed.•Challenges associated with g-C3N4, hindering its overall performance are also identified.•Properties of g-C3N4 were discussed in details.•Synthesis method of g-C3N4 and modification strategies were explained and discussed in details.