Tuning Band Alignments and Charge-Transport Properties through MoSe2 Bridging between MoS2 and Cadmium Sulfide for Enhanced Hydrogen Production

ACS Appl Mater Interfaces. 2018 Aug 8;10(31):26153-26161. doi: 10.1021/acsami.8b02093. Epub 2018 Jul 26.

Abstract

Transition-metal dichalcogenide materials play a major role in the state-of-the-art innovations for energy conversion because of potential applications resulting from their unique properties. These materials additionally show inordinate potential toward the progress of hygienic power sources to deal with increasing environmental disputes at the time of skyrocketing energy demands. Herein, we report earth-abundant, few-layered, MoSe2-bridged MoS2/cadmium sulfide (CdS) nanocomposites, which reduce photogenerated electron and hole recombination by effectively separating charge carriers to achieve a high photocatalytic efficiency. Accordingly, the MoSe2-bridged MoS2/CdS system produced effective hydrogen (193 μmol·h-1) as that of water using lactic acid as a hole scavenger with the irradiation of solar light. The presence of few-layered MoSe2 bridges in MoS2/CdS successfully separates photogenerated charge carriers, thereby enhancing the shuttling of electrons on the surface to active edge sites. To the best of our knowledge, this few-layered MoSe2-bridged MoS2/CdS system exhibits the most effective concert among altogether-reported MoS2-based CdS composites. Notably, these findings with ample prospective for the development of enormously real photocatalytic systems are due to their economically viable and extraordinary efficiency.

Keywords: MoS2, MoSe2; band gap tuning; exfoliation; nanocomposite; photocatalytic H2 production; transition-metal dichalcogenides.