Modulating electronic structure of lattice O-modified orange polymeric carbon nitrogen to promote photocatalytic CO2 conversion

Adsorption and activation of CO2, and high carriers transform efficiency are of great significance for improving the CO2 photoreduction performance. However, electronic structure regulation plays an important role in the dynamical behavior of carriers. In this study, O atoms were successfully introduced into polymeric carbon nitrogen to synthesize an orange O-modified polymeric carbon nitrogen and achieve the rearrangement of electron density distribution, which promotes the adsorption and activation of CO2 and efficient separation and migration of carriers. DFT calculation demonstrates that the O atoms perform as the dominant active sites and reduce the free energy of determining step. Moreover, the introduction of O atoms broadens the light absorption range by changing the electronic layer structure of polymeric carbon nitrogen. Therefore, the fabricated O-modified polymeric carbon nitrogen exhibits significant performance. Under visible light irradiation, the CO generation efficiency achieved a 10-fold boost. We synthesize theory and experiment to highlight the important role of modulating electronic structure in designing photocatalysts. [Display omitted] •Under visible light irradiation, the CO generation efficiency achieved a 10-fold boost by using O-PCN.•The modulating of electronic structure is critical to the adsorption and activation of CO2 molecules.•O-doping provides additional advantageous active sites and promotes the activity of surrounding N sites.•The O-PCN exhibits changing the rate-determining step and reducing the reaction energy barrier compared with PCN.