Facile Synthesis of ZIFs-derived Hollow Bimetal (Zn, Co) S Nanocrystals for Supercapacitors

A simple two-step method was introduced to synthesize uniform and hollow (Zn, Co) S nanostructures. Firstly, the bimetal compound ZIF-Zn, Co (ZIF = zeolitic imidazolate frameworks) with metal ions (Zn2+ and Co2+) and ligand(2-methylimidazole) was obtained using deionized water as solvent, hexadecyltrimethylammonium bromide(CTAB) as capping agent under stirring at room temperature. Secondy, hollow (Zn,Co)S nanostructures were synthesized by selecting ZIF-Zn, Co as self-sacrificial template and adding thioacetamide (TAA) as sulfate source under the microwave-assisted heating condition. The electrochemical measurements show that the specific capacitance of the as-made hollow (Zn, Co) S nanostructures was 423.3 F/g at current density of 3 mA/cm(2) and 57% capacitance remains after 2000 cycles at a current density of 10 mA/cm2. With the advantages of unique properties, such as high surface area and good electrochemical performance, the as-made hollow (Zn, Co) S nanostructures have great potential as electrode material for supercapacitors.