Synthesis of hollow Cu@Cu3−xP core-shell nanostructure as dual-functional catalyst with copper vacancy for enhancing chemical reduction and photocatalytic performance

As an important family of semiconductors, transition metal phosphides could act as effective catalysts in the treatment of organic pollutants. Herein, a novel hollow core–shell Cu@Cu 3−x P catalyst with copper vacancies, possessing excellent properties of photocatalytic and catalytic reduction for organic pollutants, was prepared by the vapor deposition method. 4-Nitrophenol (4NP) (50 μM, 3 mL) could be degraded within 2 min under the action of catalyst (0.06 mg), and the reduction rate was approached to 99.8%. Meanwhile, this catalyst displayed prominently increased Rhodamine B (RhB) photo-oxidation performance, about 1.7 and 16 times more than the bare Cu 3 P and Cu under optimal conditions (5% Cu@Cu 3−x P). Such superior catalytic performance can be ascribed to the mutual contribution of Cu vacancy (convert the band structure and supply active sites) and Cu nanowire (prevent agglomeration of Cu 3 P nanoparticles and promote the transfer of photoelectrons) and the unique hollow core–shell architecture(the rapid separation and low recombination of photoelectron-hole). The possible pathways of 4NP reduction and RhB photo-oxidation were proposed according to the results of degradation products obtained from HPLC, LC-Q-orbitrap/MS, GC-MS, and ATR-FTIR. This study can validate the extensive application of Cu@Cu 3−x P and provide a new insight for the synthesis of dual-functional catalysts containing metal defects.