Data from: Enhanced cycle stability of a NiCo2S4 nanostructured electrode for supercapacitors fabricated by the alternate-dip-coating method

Nanostructured nickel cobalt sulfide (NiCo2S4) electrodes are successfully fabricated using a simple alternate-dip-coating method. The process involves dipping a TiO2 nanoparticles-covered substrate in a nickel/cobalt precursor solution and sulfur precursor solution alternately at room temperature. The fabricated bimetallic sulfide electrode exhibits a synergetic improvement compensating for the disadvantages of the two single metal sulfide electrodes, i.e. the poor cycle stability of the nickel sulfide electrode and the low specific capacitance (C) of the cobalt sulfide electrode. The two capacitive properties are optimized by adjusting the ratio of nickel and cobalt concentrations in the metal precursor solution, reaching a C of 516 F/g at a current density of 1 mA/cm2 and its retention of 99.9 % even after 2000 galvanostatic charge-discharge cycles.本研究采用简易交替浸涂法成功制备了纳米结构镍钴硫化物（NiCo₂S₄）电极。该制备工艺为：在室温条件下，将负载二氧化钛（TiO₂）纳米颗粒的基底交替浸入镍/钴前驱体溶液与硫前驱体溶液中。所制备的双金属硫化物电极可实现协同增效，弥补两种单金属硫化物电极的固有缺陷——即硫化镍电极循环稳定性差、硫化钴电极比电容（C）较低的问题。通过调控金属前驱体溶液中镍与钴的浓度配比，可优化其两项电容性能：在1 mA/cm²的电流密度下，该电极的比电容可达516 F/g，且即便经过2000次恒流充放电循环后，其电容保持率仍高达99.9%。