Atomic heterojunction-induced accelerated charge transfer for boosted photocatalytic hydrogen evolution over 1D CdS nanorod/2D ZnIn2S4 nanosheet composites

Design of highly efficient heterojunctions for photocatalytic hydrogen evolution is of significant importance to address the energy shortage and environmental crisis. Nevertheless, the smart design of semiconductor-based heterojunctions at the atomic scale still remains a significant challenge hitherto. Herein, we report novel atomic CdS/ZnIn2S4 heterojunctions by in-situ epitaxially growing 2D ZnIn2S4 nanosheets onto the surface of 1D defective CdS nanorods. The strong electronic coupling between defective CdS and ZnIn2S4 is confirmed by transient photocurrent response measurements, •O2− and •OH radicals experiments, and PL results, leading to accelerated interfacial charge separation and transfer. Additionally, the elevated charge transfer and electronic coupling are further confirmed by theoretical calculations. Consequently, CdS/ZnIn2S4 hybrids exhibit superior photocatalytic hydrogen generation activity to pristine CdS. Our findings offer a new paradigm for designing atomic 1D/2D heterojunctions for efficient solar-driven energy conversion.