From amorphous to crystalline: in situ growth Ni-Co chalcogenides hybrid nanostructure on carbon cloth for supercapacitor

In this work, Ni-Co chalcogenides with controllable amorphous structure were successfully grown on carbon cloth via a facile surfactant-assisted hydrothermal route. The interacted reaction between NiCo2(OH)(6) precursor and thioacetamide plays a critical role in altering the morphology and crystal structure of Ni-Co chalcogenides. The varying active sites in NiCo2(OH)(6) and the H2S gas decomposed from thioacetamide are found to be the key factors for the formation of amorphous Ni-Co chalcogenides. By benefiting from the amorphous structure and hybrid nanosheet morphology, the as-prepared Ni-Co chalcogenides delivers a specific capacitance of 2361.5Fg(-1) while retaining 75.8% of its highest capacitance over 2000 cycles at 20Ag(-1). The crystallized NiCo2S4 possesses excellent cycling stability but low specific capacitance. This work paves a promising and simple way for precise synthesis amorphous/crystal metal chalcogenides as active materials in aqueous supercapacitors and other high-performance energy storage devices.