High-Efficiency g-C₃N₄ Based Photocatalysts for CO₂ Reduction: Modification Methods

Abstract

Photocatalysis is an effective means to solve the greenhouse effect caused by the large amount of carbon dioxide (CO₂) emissions from fossil fuel consumption. Graphitic carbon nitride (g-C₃N₄) has the advantages of suitable band gap, easy preparation, low price, and good stability, making it a promising semiconductor photocatalyst. However, bulk g-C₃N₄ also has disadvantages such as low gas adsorption, low photocatalytic efficiency, narrow spectral response, and easy recombination of electron–hole pairs. The modification method based on g-C₃N₄ photocatalyst helps to improve the above-mentioned problems. This review summarizes the research progress in recent years from four aspects: morphology adjustment, co-catalysts, heterostructures and doping. Each aspect includes the pros and cons of different improvement methods, the comparison of theoretical calculations and experimental results, the application of different characterization methods, and the detailed listing of product yield and selectivity. Prior to this, there was an explanation of the basic theory of semiconductor photocatalytic CO₂ reduction. Finally, the future challenges and development prospects are also briefly prospected.

Funding

Key Program for International S&T Cooperation Program of China(2017YFE0113000); National Natural Science Foundation of China(52072241); Shanghai Science and Technology Committee(18ZR1420900); National Key Research and Development Program(YS2017YFGH000385)