Due to the ability of cocatalysts to form heterojunctions on the surface in contact with g?C₃N₄, promoting the migration of photo generated electrons and enhancing the photocatalytic performance of g?C₃N₄, the introduction of cocatalysts plays a significant role in improving the photocatalytic activity of g?C₃N₄. Common co?catalysts can be broadly categorized into three groups: transition metal?based cocatalysts (non?precious?metal co?catalysts), precious metal based co?catalysts, and non?metal cocatalysts. Among them, transition metal?based cocatalysts have attracted widespread attention due to their low cost and strong ability to capture electrons. This article focuses on the composite methods, mechanisms of action, and their effects on the photocatalytic performance of various transition metal based cocatalysts (such as metal oxides, sulfides, phosphides, etc.) with g?C₃N₄, aiming to provide comprehensive theoretical and practical guidance for the design and development of efficient g?C₃N₄ based photocatalysts.

Nanocarbon particles/carbon nitride composite was prepared through one step heat polymerization method. XRD, FTIR, TEM, UV?vis DRS, PL and other methods were used to systematically characterize nanocarbon particles/carbon nitride. Rhodamine B solution was degraded to measure its photocatalytic performance. The results show that the loading of nanocarbon particles can obviously improve visible light absorbed ability of the composite material and the separation efficiency of photogenerated electrons/holes. When the added mass of nanocarbon particles is 10 mg, the rhodamine B degradation rate of as?prepared nanocarbon particles/carbon nitride 2 is 96.5% in the 20 min, which is obviously better than bare carbon nitride. In addition, nanocarbon particles/carbon nitride composites show good stability.