文摘
Two-dimensional layered chalcogenide WS2, similar to graphene, is considered to be very interesting for materials scientists. However, to make it a useful material platform, it is necessary to develop sophisticated synthesis methods to control its morphology. In this paper, we present a simple approach to prepare various morphologies of WS2 nanostructures by direct thermal evaporation of WO3 and S powders onto Si substrates sputtered with W film without using any nanostructured W-contained precursors and highly toxic sulfide gases. This method can produce bulk quantities of pure hexagonal, horizontally grown WS2 nanoplates, vertically grown nanoplates, and nanoplate-formed flowers simply by tuning the distance between the substrate and source powders. The synthesis mechanism and morphology evolution model were proposed. Moreover, when employed as a thin-film anode material, the Li-ion battery with as-prepared, vertically grown WS2 nanoplates presented a rechargeable performance between 3 and 0.01 V with a discharge capacity of about 773 mAh/cm3 after recycling three times, much better than its already-reported counterparts with randomly distributed WS2 nanosheet electrodes, but the battery with horizontally grown WS2 nanoplates could not show any charge–discharge cycling property, which could be attributed to the different structures of WS2 anodes for Li+ ion intercalation or deintercalation.