硫化镍/氮掺杂碳纳米管复合材料及其超级电容器性能

Preparation and supercapacitor performance of NiS-NCNTs composite

采用惰性气氛热处理方法,以氮掺杂碳纳米管(NCNTs)为载体,二乙基二硫代氨基甲酸镍(C_(10)H_(20)N_2NiS_4)为NiS前驱体,制备NiS-NCNTs复合材料。研究了热处理温度对复合材料微观形貌、组织结构及其作为超级电容器电极材料特性的影响。400℃下,C_(10)H_(20)N_2NiS_4热解反应生成α-NiS,导致NiS-NCNTs复合材料形成,但低温热解反应导致NiS颗粒大,且数量少。500℃下,形成的α-NiS粒径小且数量增多。当温度升至600℃时,α-NiS向β-NiS转变,且有新相Ni9S8形成。其中500℃制备的NiS-NCNT500具有最高的利于离子传输的2~5nm中小孔体积,及电荷堆积的高比表面积,其作为超级电容器电极材料,展现出较高的比电容量和良好的充放电循环稳定性。

The composite NiS-NCNTs was prepared by using the nitrogen doped carbon nanotubes （NCNTs） and the C10H20N2NiS4 as the support and the precursor of NiS, respectively, through the heat treatment method. The influence of treatment temperature on the morphology, structure, texture and supercapacitor performance of the composite materials was investigated. At 400 ℃, the pyrolysis of C10H20N2NiS4 results into the formation of α-NiS, and thus the composite of NiS-NCNTs was formed. However, the small amount of NiS with large particle size is produced at 400℃ since the low temperature. At 500 ℃, the size of NiS become smaller and its amount increases. At 600℃, the α-NiS transforms to β-NiS and the new phase of Ni9S8 formed. The NiS-NC- NT500 prepared at 500℃ owns the highest volume of mesopores with size of 2-5 nm, facilitating ion transport, and the largest specific surface area for charge accumulation. Therefore, as the electrode materials of supercapacitor, it exhibits a high specific capacitance and good durability of chare-discharge cycles.