Facile synthesis and efficient photoelectrochemical reaction of WO3/WS2 core@shell nanorods utilizing WO3•0.33H2O phase

One-dimensional (1D) WO3/two-dimensional (2D) WS2 heterojunction nanostructures are of great interest in various photoelectrochemical (PEC) and electrochemical applications. In this study, we introduced a simple and effective route to synthesize 2D WS2 shell layer on WO3 nanorods by utilizing WO3 center dot 0.33H(2)O phase. The formation of WO3 center dot 0.33H(2)O nanorods was critically affected by hydrothermal reaction temperature. The WO3 center dot 0.33H(2)O phase was preferentially transformed into hexagonal WO3 and 2D WS2 through oxidation and sulfurization at 450 degrees C, respectively. The 2D WS2 shell layer was more favorably formed on WO3 nanorods, which were synthesized at 180 degrees C and possessed a significant amount of WO3 center dot 0.33H(2)O phase (referred to as W-180), than on WO3 nanorods with predominant monoclinic WO3 phase, which were synthesized at 200 degrees C (referred to as W-200). Thus, the WO3/WS2 core@shell nanorods from W-180 exhibited significantly enhanced PEC performance because of the improved charge transfer properties attributed to the advantageous heterojunction effect of 1D WO3/2D WS2. The new synthesis route from WO3 center dot 0.33H(2)O phase to 2D WS2 can be applied to synthesize various WO3/2D WS2 heterojunction nanostructures, such as thin films, nanoparticles, and nanorods. (C) 2021 Elsevier B.V. All rights reserved.