Controlled synthesis of zinc cobalt sulfide nanostructures in oil phase and their potential applications in electrochemical energy storage

摘要

A unique controlled synthesis of zinc cobalt sulfide nanostructures is obtained by a facile oil phase approach. Nanoartichokes composed of self-assembled nanosheets and nanoparticles have been fabricated by using different sulfur sources. The application of such nanomaterials is demonstrated as electrodes for supercapacitors and lithium-ion batteries. Serving as lithium-ion battery electrodes, the ZnxCo1-xS nanoartichokes deliver a higher specific capacity of 750 mA h g(-1) during the 100th cycle as compared to only 220 mA h g(-1) for nanoparticles. In supercapacitor tests, the ZnxCo1-xS nanoartichokes possess an improved specific capacitance (486.2 F g(-1) at a current density of 2.0 A g(-1)) and excellent cycling stability (retaining 86.4% after 2000 cycles), both of which are much higher than those of nanoparticles (e.g. 406.7 F g(-1) and 73.3%). This effective nanostructure design of ternary transition metal sulfides could provide a promising method to construct high-performance materials for energy and environment applications.