Is g-C3N4 more suitable for photocatalytic reduction or oxidation in environmental applications?

Graphitic carbon nitride (g-C₃N₄), as an efficient semiconductor photocatalyst with an excellent tunable bandgap, a high physicochemical stability and a proper optical performance, has shown its non-negligible potential in multifarious photocatalytic reactions, such as hydrogen (H₂) evolution, carbon dioxide (CO₂) reduction, hydrogen peroxide (H₂O₂) production, pollutants degradation and so on. However, considering the solar light transfer efficiency, the accurate reaction mechanisms as well as the limitations of various reactions, is g-C₃N₄ more suitable for reduction or oxidation reactions? In this perspective, we think g-C₃N₄ might be more suitable for photocatalytic reduction reactions since the performances of single oxidation reactions maybe not ideal and sometimes the electrons are still essential during such a process.