Synthesis, characterization and electrochemical performance of ZnxNi1-x(OH)2 nanostructured layered double hydroxide active material for supercapacitors

In this research, ZnxNi1-x(OH)2 nanostructured layered double hydroxide active materials were successfully synthesized by a chemical co-precipitation route using polyethylene glycol as the structure-directing reagent. Structural characterizations were performed using X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), and morphology of materials was obtained by Field Emission Scanning Electron Microscopy (FESEM). The results show that the as-prepared materials have a porous structure with nanoscale walls and their crystal structure was mainly ?-phase. Electrochemical experiments using cyclic voltammetry, galvanostatic charge-discharge and cyclability show that Zn0.33Ni0.67(OH)2 active material has the highest initial specific capacitance of 926 F g-1 at a current density of 1 A g-1 and a capacity retention of about 98% after 100 charge-discharge cycles.