Synergistically interactive P–Co–N bonding states in cobalt phosphide-decorated covalent organic frameworks for enhanced photocatalytic hydrogen evolution

Abstract

Non-noble materials with high efficiency and stability are essential for renewable energy applications. Herein, cobalt phosphide nanoparticles-decorated covalent organic frameworks (CTF-CoP) are synthesized via an in situ self-assembly method combined with the calcination process. In such a configuration, an intimate interaction between CoP and CTF matrix is gained through the Co–N chemical bonds, which not only significantly enhance the recyclability of CoP nanoparticles but also significantly improve the charge separation efficiency. Besides, the synergistically interactive P^δ−–Co^δ+–N^δ− states induced by the polarization effect of N-anchoring sites benefit for the adsorption and dissociation of water molecules in CTF-CoP. Consequently, CTF-CoP exhibits a higher photocatalytic hydrogen evolution rate (261.7 μmol g⁻¹ h⁻¹) and better durability as compared with the physically fixed CTF/CoP composite (64.8 μmol g⁻¹ h⁻¹) and even the noble metal-based CTF-Pt (191.3 μmol g⁻¹ h⁻¹). This work provides an avenue to construct highly stable non-noble photocatalyst for energy conversion and also emphasizes the potential of CTFs in constructing efficient heterojunctions.