CuO/CuS microstructure regulation towards high efficiency photocatalytic hydrogen production and its theoretical mechanism analysis

Cu 2 O with a cubic structure was prepared by a water bath method, and then a Cu 2 O/Cu 2 S core-shell material was obtained by the redox reaction of Cu 2 O and Na 2 S with the prepared cubic Cu 2 O as a template and Na 2 S·9H 2 O solution as the reaction solution. At the same time, the effect of sulfidization time on the Cu 2 O/Cu 2 S structure and photohydrogen production performance was studied. The structure of the samples was further confirmed and characterized through SEM, HRTEM, XRD and XPS. The photohydrogen production properties of the Cu 2 O/Cu 2 S composites with different morphologies were tested. The flower-shaped hollow structure of Cu 2 O/Cu 2 S can be obtained by proper sulfidization, and the hydrogen production can reach 1076.95 μmol g −1 after 5 h of illumination. Then, through photocurrent response and impedance spectrum tests and DFT calculations, it is proved that the Cu 2 O/Cu 2 S heterostructure can effectively improve the photoresponse ability and carrier transport properties. It was confirmed that the interfacial charge transfer in Cu 2 O/Cu 2 S helped increase the photocatalytic hydrogen production performance. Compared with cubic Cu 2 O, the Cu 2 O/Cu 2 S composite exhibits better photocatalytic hydrogen production. The catalytic hydrogen production of the Cu 2 O/Cu 2 S heterostructure reached 1076.95 μmol g −1 after 5 h of illumination.