One-step preparation of novel K+ and cyano-group co-doped crystalline polymeric carbon nitride with highly efficient H2 evolution

Abstract

Polymeric carbon nitride (PCN) is a helpful photocatalyst in photocatalysis field, but low carrier separation efficiency and poor crystallinity resulted its ability unsatisfactory. Herein, we developed one step thermopolymerization method to introduce crystallinity and doped engineering into PCN system. In detail, K+ and cyano-group co-doped crystalline PCN (KC-CCN) was successfully prepared through one-step thermopolymerization method with the precursor of thiourea and potassium thiocyanate, and showed a highly crystal structure, stronger light harvesting and significantly electron-hole separation rate. When it was used for photocatalysis hydrogen production in presence of Pt as co-catalyst, the H2 production rate of KC-CCN presented 16.8 times more than amorphous one. Furthermore, steady photocatalytic performance and chemical structure also maintained after several recycling experiments. Evidently, this paper affords a valid and simple method for the preparation of doped engineering modified crystalline PCN.