MS2 (M = Co and Ni) Hollow Spheres with Tunable Interiors for High‐Performance Supercapacitors and Photovoltaics

We demonstrate in this paper facile synthesis of CoS₂ and NiS₂ hollow spheres with various interiors through a solution‐based route. The obtained CoS₂ microspheres constructed by nanosheets display a three‐dimensional architecture with solid, yolk‐shell, double‐shell, and hollow interiors respectively, with continuous changes in specific surface areas and pore‐size distributions. Especially, the CoS₂ hollow spheres demonstrate excellent supercapacitive performance including high specific capacitance, good charge/discharge stability and long‐term cycling life, owing to the greatly improved faradaic redox reaction and mass transfer. Furthermore, CoS₂ hollow spheres exhibit superior electrocatalytic activity for disulfide/thiolate (T₂/T^?) redox electrolyte in dye‐sensitized solar cells (DSCs). Therefore, this work provides a promising approach for the design and synthesis of structure tunable materials with largely enhanced supercapacitor behavior, which can be potentially applied in energy storage devices.