Sandwich structure MoO2/MoS2/TiO2 photocatalyst for superb hydrogen evolution

TiO2 has gained increasing interest because of its outstanding properties and promising applications in various fields. In this study, we report a novel MoO2/MoS2/TiO2 sandwich heterostructure that was prepared by chemical vapor deposition (CVD) for highly efficient photocatalytic H-2 generation. The sandwich structure, consisting of a MoS2 nanoflake layer and a MoO2 nanoplate layer with large specific surface area, was grown on TiO2 nanotube array electrodes. The MoO2 acts as a fast hole transport layer that promotes efficient charge separation. Since the MoO2/MoS2/TiO2 heterostructure has a nearly fullsolar-spectrum absorption range, its photocatalytic activity for water splitting is enhanced, resulting in a H-2 production rate of 110 mu mol h(-1) cm(-2). This work provides a bottom-up strategy for preparing highly efficient sandwich-type photocatalysts. (C) 2020 Elsevier B.V. All rights reserved.