Graphitic carbon nitride (g-CN)-based photocatalysts for solar hydrogen generation: recent advances and future development directions

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2017, Vol.5 (45), p.2346-23433
• Main Authors: Naseri, Amene, Samadi, Morasae, Pourjavadi, Ali, Moshfegh, Alireza Z, Ramakrishna, Seeram
• Format: Article
• Language: English
• Subjects: Carbon nitride; Commercialization; Electronic structure; Fabrication; Hydrogen; Hydrogen production; Metal sheets; Nanocomposites; Nanomaterials; Nanotechnology; Photocatalysis; Photocatalysts; Photochemicals; Water splitting
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c7ta05131j

Graphitic carbon nitride (g-C 3 N 4 ) is a metal-free conjugated polymer constructed from two-dimensional sheets with a bandgap energy of 2.7 eV, which makes it an applicable and efficient visible-active photocatalyst for H 2 production. In the present study, the basic concepts and principles of photocatalytic water splitting have been discussed, and a guide for the selection of appropriate photocatalysts, focusing on the g-C 3 N 4 nanomaterials, has been proposed. Our approach is mainly concentrated on evaluating two factors, namely the solar-to-hydrogen (STH) conversion and apparent quantum yield (AQY) for different photocatalysts, to provide an in-depth analysis and a framework for solar H 2 production for future research directions. We compared hydrogen production from an economic viewpoint and performance of g-C 3 N 4 nanomaterials through photochemical (PC) and photoelectrochemical (PEC) methods. Various approaches for efficient solar H 2 generation over a modified g-C 3 N 4 surface with the possibility for commercialization have been introduced. The promising approaches for the effective utilization of g-C 3 N 4 are categorized into three proposed methods: electronic structure tuning, hybrid and nanocomposite fabrication, and finally geometric structure manipulation. Finally, we compared the recent findings and key achievements for g-C 3 N 4 -based photocatalysts modified based on the abovementioned three approaches to propose two possible scenarios for their use in the future development of efficient solar H 2 generation. Analyzing the commercialization potential of g-C 3 N 4 photocatalysts for solar H 2 generation from an economic viewpoint and for large-scale production.