Promoted reactants activation and charge separation leading to efficient photocatalytic activity on phosphate/potassium co-functionalized carbon nitride

Abstract Photocatalytic technology has been widely adopted to address the issue of air pollution. The separation of photogenerated carriers and the activation of reactants on catalyst surface are the main factors that affect the photocatalytic efficiency. Here, the phosphate/potassium (PO 4 /K) co-functionalized carbon nitride (labeled as PO 4 -CN-K) was synthesized via a one-step in situ co-pyrolysis of thiourea and potassium phosphate. The unique electronic structure of PO 4 -CN-K could significantly improve the performance of photocatalytic NO purification. The enhanced activity of PO 4 -CN-K can be attributed to the promoted activation capacity for O 2 , NO and H 2 O on the catalyst surface, the decreased of carriers recombination, benefiting from the co-functionalization of phosphate groups on the surface of CN and the construction of K channels between CN layers. The photocatalytic NO conversion pathway is disclosed through time-dependent in situ FT-IR, indicating that PO 4 -CN-K can efficiently convert NO molecules into harmless nitrate via the NO→NO + →nitrate/nitrite routes. The research provides a novel strategy to impel the development of photocatalytic technology for efficient air purification.