Morphology-Dependent ZnO/MoS2 Heterostructures for Enhanced Photoelectrochemical Water Splitting

Abstract

This study reports the synthesis of ZnO nanosheets, nanorods, and nanotubes through electrodeposition, followed by the deposition of MoS₂ layers using RF magnetron sputtering to create ZnO/MoS₂ heterostructures. The morphological and structural properties of these materials were characterized using various techniques, including X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–visible spectroscopy. The photoelectrochemical (PEC) performance of synthesized ZnO and ZnO/MoS₂ heterostructures for water splitting was evaluated. Results indicate that the morphology of ZnO significantly influences the PEC activity of the ZnO/MoS₂ heterostructures. The ZnO/MoS₂ heterostructure with ZnO nanotubes exhibited the highest PEC performance, achieving a photocurrent density of ∼1.28 mA/cm² at 1.65 V versus reversible hydrogen electrode, which is 2.5 times greater than that of the pristine ZnO nanotube photoanode. This study suggests that ZnO/MoS₂ heterostructures can be promising photoanodes for efficient hydrogen production through PEC water oxidation.