Rational heterojunction design of 1D WO 3 nanorods decorated with vertical 2D MoS 2 nanosheets for enhanced photoelectrochemical performance

The development of the heterostructures of one-dimensional (1D) and two-dimensional (2D) semiconductors is a prospective strategy to design an efficient photoanode for photoelectrochemical (PEC) water splitting. In this study, we report the controllable growth and beneficial heterojunction effects of vertically-aligned 2D MoS 2 nanosheets (NSs) on 1D WO 3 nanorods (NRs) for efficient PEC water-splitting reactivity. MoS 2 NSs were decorated on WO 3 NRs by metal–organic chemical vapor deposition. In comparison with pristine WO 3 NRs, vertical MoS 2 NSs-decorated WO 3 NRs possessed an enlarged surface area, improved light absorption performance, and appropriately organized the staggered heterojunction of MoS 2 /WO 3 for promoting the PEC reaction. PEC performance was considerably affected by the size of vertical MoS 2 NSs. MoS 2 /WO 3 structure with appropriate MoS 2 NS size showed a 72% enhancement in PEC performance compared with pristine WO 3. These results provide a valuable strategy for constructing staggered heterojunctions and introducing morphology control for beneficial PEC applications.