Tungsten Sulfide Enhancing Solar-Driven Hydrogen Production from Silicon Nanowires

Tungsten sulfides, including WS₂ (crystalline) and WS₃ (amorphous), were introduced to silicon nanowires, and both can promote the photoelectrochemical hydrogen production of silicon nanowires. In addition, more enhancement of energy conversion efficiency can be achieved by the loading of WS₃, in comparison with loading of WS₂. Polarization curves of WS₃ and WS₂ suggest that WS₃ has higher catalytic activity in the hydrogen evolution reaction than WS₂, affording higher energy conversion efficiency in silicon nanowires decorated with WS₃. The higher electrocatalytic activity of WS₃ correlates with the amorphous structure of WS₃ and larger surface area of WS₃, which result in more active sites in comparison with crystalline WS<sub>2