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采用快速冷冻沉淀法制备出了非晶态纳米氢氧化镍。对制得材料样品进行了XRD,SEM,TEM,DSC和比表面积与孔径分析,将其制成MH-Ni电池正极材料进行充放电性能测试。结果表明:材料粉体为非晶态,颗粒粒度为纳米级,类似球形。非晶纳米Ni(OH)2的热分解温度286.4℃低于常规球形Ni(OH)2的热分解温度333.8℃,同时具有较大得比表面积和孔径,分别为76.2089m2·g-1和37.7nm。与普通β-Ni(OH)2相比较,非晶态纳米氢氧化镍电极充电电压低,放电电压平台时间长,且高达1.258V,放电比容量为349.85mAh/g,具有较好的循环性能,20次循环后其容量衰减仅为1.28%。
Amorphous nano-nickel hydroxide was prepared by rapid freeze-precipitation method. The prepared samples were characterized by XRD, SEM, TEM, DSC and surface area and pore size analysis. The samples were made into MH-Ni battery cathode materials for charge-discharge test. The results show that the material powder is amorphous, the particle size is nanometer, similar to spherical shape. The thermal decomposition temperature of amorphous Ni (OH) 2 is 286.4 ℃ lower than the thermal decomposition temperature of conventional spherical Ni (OH) 2 333.8 ℃, and has a large specific surface area and pore size of 76.2089m2 · g-1 and 37.7 nm. Compared with common β-Ni (OH) 2, amorphous nickel hydroxide electrode has low charge voltage, long discharge voltage platform, up to 1.258V and discharge capacity of 349.85mAh / g, which has good cycle performance , Its capacity decay is only 1.28% after 20 cycles.