覆镍硅微通道板用于三维超级电容器的研究

Three-dimensional nickel-coated silicon microchannel plates for supercapacitors

采用无电镀方法在硅微通道板上制备镍,然后进一步通过化学液相沉积法,在其上面制备了氢氧化镍纳米晶体,获得了一种具有独特三维结构的Si-MCP/Ni/Ni(OH)_2超级电容器.研究发现,制得的氧氧化镍晶体由许多纳米薄片组成,XRD图谱显示其具备α和β两种晶型.通过循环伏安和计时电位法对该超级电容器进行了性能测试.在放电电流为10 mA时,样品获得最大放电比容量,为2 150 F/g.在多次循环测试中,样品的稳定性良好.随着退火温度的升高,样品的容量下降.研究发现氢氧化镍的表面积减小是导致容量衰减的主要原因.由于该电容器有着巨大的比容量和良好的稳定性,该三维结构有望应用于二次电源和相关器件中.

A unique three-dimensional Si-MCP/Ni/Ni（OH）2 structure for supercapacitor was produced. Chemical liquid deposition was carried out to grow nano-sized Ni（OH）2. The as-pre- pared Ni（OH）2 film consists of many intertwined nano-flakes with both the a- and ~t-Ni（OH）2 phases. The formation mechanism of Ni（OH）2 was introduced. The as-prepared and annealed materials were evaluated electrochemically by cyclic voltammetry and chronopotentiometry. The cyclic voltammetry results reveals a typical redox characteristic of the sample. A specific capaci- tance of 2 150 F/g was observed at a discharge current of 10 mA, and the structure has high sta- bility in prolonged charging and discharging experiments. The capacitance of the annealed sample decreases as the annealing temperature increases. Surface morphology of the samples after 2 000 cycles and annealed samples were observed. Decrease of the surface area of Ni（OH）2 is consi- dered as the main reason of the capacitive loss. Owing to the large specific capacitance and goodstability, the unique structure is suitable for electrochemical super-capacitors used in secondary power sources and devices.