g-C₃N₄-Based Photocatalytic Materials for Converting CO₂ Into Energy: A Review

Environmental pollution management and renewable energy development are humanity's biggest issues in the 21st century. The rise in atmospheric CO₂, which has surpassed 400 parts per million, has stimulated research on CO₂ reduction and conversion methods. Presently, photocatalytic conversion of CO₂ to valuable hydrocarbons enables the transformation of solar energy into chemical energy and offers a novel avenue for energy conversion while regulating the greenhouse effect. This is an ideal strategy for simultaneously addressing environmental issues and the energy crisis. Photocatalysts are essential to photocatalytic processes. Photocatalyst is the core of photocatalytic technology, and graphite carbon nitride (g-C₃N₄) has attracted much attention because of its nonmetallic characteristics, and it has the characteristics of low cost, tunable electronic structure, easy manufacture and strong reducibility. However, its activity is not only affected by external reaction conditions, but also by the band gap structure, physical and chemical stability, surface morphology and specific surface area of the photocatalyst it. In this paper, the application progress of g-C₃N₄-based photocatalytic materials in CO₂ reduction is reviewed, and the modification strategies of g-C₃N₄-based catalysts to obtain better catalytic efficiency and selectivity in CO₂ photocatalytic reduction are summarized, and the future development of this material is prospected.