Selective-Epitaxial Hybrid of Tripartite Semiconducting Sulfides for Enhanced Solar-to-Hydrogen Conversion

The design and synthesis of advanced semiconductors is crucial for the full utilization of solar energy. Herein, colloidal selective-epitaxial hybrid of tripartite semiconducting sulfides CuInS2-Cd(In)S-MoS2 heteronanostructures (HNs) via lateral- and vertical-epitaxial growths, followed by cation exchange reactions, are reported. The lateral-epitaxial CuInS2 and Cd(In)S enable effective visible to near-infrared (NIR) solar spectrum absorption, and the vertical-epitaxial ultrathin MoS2 offer sufficient edge sulfur sites for the hydrogen evolution reaction (HER). Furthermore, the integrated structures exhibit unique epitaxial-staggered type II band alignments for continuous charge separation. They achieve the H-2 evolution rate up to 8 mmol h(-1) g(-1), which is approximate to 35 times higher than bare CdS and show no deactivation after long-term cycling, representing one of the most efficient and robust noble-metal-free photocatalysts. This design principle and transformation protocol open a new way for creating all-in-one multifunctional catalysts in a predictable manner.

Automated summary

This study reports a new type of semiconductor heteronanostructures, which are synthesized through lateral and vertical epitaxial growths and cation exchange reactions. These structures exhibit effective solar spectrum absorption and high hydrogen evolution reaction efficiency. The unique band alignment enables continuous charge separation, leading to efficient and stable photocatalytic performance. This design principle and transformation protocol provide a new approach for the creation of multifunctional catalysts in a predictable manner.