Graphene oxide coupled high-index facets CdZnS with rich sulfur vacancies for synergistic boosting visible-light-catalytic hydrogen evolution in natural seawater: Experimental and DFT study

Abstract

Constructing photocatalysts with high activity and anti-photocorrosion is a key to harvesting hydrogen energy from seawater efficiently. Herein, graphene oxide closely coupled high-index facets CdZnS with rich sulfur vacancies (Vs-CZS@GO) has been successfully synthesized via one-pot sulfidation accompanied pyrolysis. DFT calculation confirmed the delicate surface/interface/defect engineering endowed high-index facets Vs-CZS@GO with a lower ΔGH* value and significant charge transfer behavior for efficient H2-generation. The synergistic effect of sulfur vacancy, high-index facets, and tightly coupling interface not only enhanced intrinsic active sites and carrier separation efficiencies, but also greatly promoted H2 evolution rate and stability. Consequently, Vs-CZS@GO displayed a significantly high H2-generation rate of 23.2 mmol∙g−1∙h−1 in natural seawater under visible-light irradiation, which is up to 82% of that in pure water. This work provides deeply insight into the synergistic regulation of electronic structure for exposed high-index facets photocatalysts via defect engineering and interface engineering for synergistic boosting visible-light-to-H2 evolution.