Coupling of Crumpled-Type Novel MoS2 with CeO2 Nanoparticles: A Noble-Metal-Free p-n Heterojunction Composite for Visible Light Photocatalytic H2 Production.

Abstract

In terms of solar hydrogen production, semiconductor-based photocatalysts via p–n heterojunctions play a key role in enhancing future hydrogen reservoir. The present work focuses on the successful synthesis and characterization of a novel p-MoS2/n-CeO2 heterojunction photocatalyst for excellent performance toward solar hydrogen production. The synthesis involves a simple in situ hydrothermal process by varying the wt % of MoS2. The various characterization techniques support the uniform distribution of CeO2 on the surface of crumpled MoS2 nanosheets, and the formation of p–n heterojunction is further confirmed by transmission electron microscopy and Mott–Schottky analysis. Throughout the experiment, it is demonstrated that 2 wt % MoS2 in the MoS2/CeO2 heterojunction photocatalyst exhibits the highest rate of hydrogen evolution with a photocurrent density of 721 μA cm–2. The enhanced photocatalytic activity is ascribed to the formation of the p–n heterojunction that provides an internal electric field to facilitate the photogenerated charge separation and transfer.