Hydrogen production using g-C3N4 based photocatalysts: A review

Photocatalytic H₂ production is a promising technique to produce green energy by using sunlight, and helpful to resolve the energy crisis and environmental issues. Graphitic carbon nitride (g-C₃N₄) is an emerging metal-free photocatalyst, easy to synthesize by earth-abundant materials and able to work in the visible light region. g-C₃N₄ exhibits multidimensional nanostructures and has been widely studied in recent years for H₂ production due to its unique electronic properties, large surface area, suitable bandgap, and exceptional physicochemical and optical properties. Different strategies have been used to enhance the H₂ yield, such as morphology modification, tuning bandgap, defect engineering, heterojunction construction, and making composites with materials. This review comprehensively elaborated the various synthesis techniques, properties of material, Z-Scheme heterostructures, and factors affecting on photocatalytic H₂ production. This review also summarizes the advancements in the g–C₃N₄–based composites and methodologies of photocatalytic water splitting. Conclusively, future recommendations on the challenges provide a new direction to design g–C₃N₄–based photocatalysts for energy and environmental applications.