Ultra-thin carbon coated amorphous N-doped CoP enhancing electron transfer for wide spectrum photocatalytic hydrogen evolution

Abstract

It is necessary that develop broad spectrum responsive and noble-metal-free photo-catalysts to produce hydrogen. Herein, a novel nitrogen doped amorphous CoP with carbon coating (N–CoP@C) photo-catalyst was prepared by phosphating the Co-alanine complex precursor for wide spectrum photocatalytic H2 production. Nitrogen doping can adjust the electronic structure, promote photogenerated carrier separation, and enhance electronic density. The improvement of photocatalytic hydrogen evolution activity is due to the porous structure and surface carbon layer of amorphous N–CoP@C. The porous and thin slice structure can increase the specific surface area, thus providing more active sites and separating surface charges. The carbon layer can be used as an electron acceptor to suppress charge recombination and improve photocatalytic performance. The amorphous N–CoP@C-4 exhibits the highest hydrogen evolution rate of 60.91 μmol h−1 under visible light irradiation with EY as a photosensitizer and TEOA as an electron donor, which is about 46.7 and 2.8 times higher than Co-alanine and CoP, respectively. In particular, a high photocatalytic reaction stability was achieved over N–CoP@C-4 catalyst. This work provides an effective strategy for construction N–CoP@C to improve the photocatalytic activity.