Visible Light-Driven Highly Selective CO Reduction to CH Using Potassium-Doped g-CN.

Establishment of an efficient and robust artificial photocatalytic system to convert solar energy into chemical fuels through CO conversion is a cherished goal in the fields of clean energy and environmental protection. In this work, we have explored an emergent low- nitrogen-rich carbon nitride material g-CN (analogue of g-CN) for CO conversion under visible light illumination. A significant enhancement of the CH production rate was detected for g-CN in comparison to that of g-CN. Notably, g-CN also showed a very impressive selectivity of 100% toward CH as compared to 21% for g-CN. The photocatalytic CO conversion was performed without using sacrificial reagents. We found that 1% K doping in g-CN enhanced its performance even further without compromising the selectivity. Moreover, 1% K-doped g-CN also exhibited better photostability than undoped g-CN We have also employed density functional theory calculation-based analyses to understand and elucidate the possible reasons for the better photocatalytic performance of K-doped g-CN.