Drastic promotion of the photoreactivity of MOF ultrathin nanosheets towards hydrogen production by deposition with CdS nanorods

This work presents a direct Z-scheme hierarchical photocatalyst based on MOF ultrathin nanosheets and CdS nanorods for H2 evolution, and opens a new vision into constructing Z-scheme systems for solar-to-chemical energy conversion. [Display omitted] •Photo-corrosion of CdS nanorods is efficiently prevented after deposited on NMOF-Ni.•Hydrogen evolution rate of NMOF-Ni sharply increases 55.6 times after modifying with CdS.•Increased light absorption and stimulated charge separation are responsible for the enhanced photoreactivity.•Direct Z-scheme mechanism is proposed for enhanced photoreactivity of CdS-NRs/NMOF-Ni. In this paper, inorganic semiconductor CdS nanorods (CdS-NRs) with strong visible-light absorption was used to modify hierarchically structured Ni-based MOF NMOF-Ni assembled from ultrathin nanosheets. It was found that the HER under simulated sunlight irradiation sharply increases 55.6 times (from 81 to 4500 μmolg−1 h−1) after modification of NMOF-Ni with 10 wt.% CdS-NRs. This enhanced performance originating from the CdS-NRs greatly improves the light absorption, and the imitate contact between NMOF-Ni and CdS-NRs stimulates the charge separation and migration. In addition, CdS-NRs/NMOF-Ni hybridized photocatalyst exhibits excellent photo-stability in hydrogen production due to the protection of NMOF-Ni, which can efficiently prevent the photo-corrosion of CdS-NRs. A direct Z-scheme electron transfer mechanism is proposed for the enhanced simulated sunlight photoreactivity of CdS-NRs/NMOF-Ni hydized photocatalyst towards hydrogen production.