Carbonate mediated hole transfer boosting the photocatalytic degradation of organic pollutants over carbon nitride nanosheets

[Display omitted] •A conceptual carbonate mediated hole transfer photocatalytic system is proposed.•carbonates can capture and transfer the photoinduced hole into solution in form of ·CO3−•Efficient hole capture via carbonates oxidation boosts the charge separation.•The unique ·CO3−/CO32− shuttle boosting charge separation for enhanced ·OH generation.•Enhanced ·OH and ·CO3− generation enables efficient organic pollutants degradation. Inspired by the important role of the manganese enzyme in photo-induced hole transfer of natural photosynthesis, we have developed an innovative carbonate-mediated-hole-transfer strategy for boosting the photocatalytic degradation of organic pollutants. We found that the carbonate species can effectively extract the photo-generated hole in the valence band of carbon nitride to generate ·CO3− and leaves electron in the conduction band for oxygen reduction to generate ·OH. The generated ·CO3− can be returned to its pristine state of CO32− via the oxidation of organic pollutants. The unique ·CO3−/CO32− shuttle could largely improve the charge separation via the fast hole extraction that leads to enhanced ·OH generation for accelerating the photocatalytic degradation of organic pollutants. As expected, the as-prepared carbon nitride exhibits markedly enhanced photocatalytic performance toward formaldehyde, p-chlorophenol, and phenol degradation than the one without carbonate as additive. The conceptual study demonstrated here may offer new viewpoints in designing high-efficient photocatalytic systems for environmental applications.