稀土Y掺杂非晶态纳米Ni(OH)2的结构及其电化学性能研究

Preparation and Performance of Y-Doped Amorphous Nano-Sized Ni(OH)2

摘要:

以Tween-80/n-C4H9OH/c-C6H12/NiSO4水溶液体系，采用微乳液快速冷冻沉淀法制备出稀土Y掺杂非晶态纳米级氢氧化镍粉体材料。采用XRD、SAED、SEM、TEM、EDS、Raman、IR，粒度分析和比表面等测试方法对所制备的粉体进行了结构形态表征，并对其充放电性能和交流阻抗谱进行测试。结果发现，适量稀土元素Y的掺入使非晶态纳米氢氧化镍的结构缺陷增多、无序性增强，平均粒度减小、比表面积增大，有利于降低其溶液电阻、电荷转移电阻和Warburg阻抗，从而提高其放电比容量。样品作为MH-Ni电池正极材料以0.2 C充放电，终止电压为1.0 V，当掺杂Y的质量分数为4%时，放电比容量达到333.3 mAh/g

Abstract:

In this paper, rare earth Y-doped amorphous nano-sized nickel hydroxide powder was prepared through the method of micro emulsion deep freeze deposition with the system of Tween-80/n-C4H9OH/c-C6H12/NiSO4 solution. XRD, SAED, SEM, TEM, EDS, Raman, IR, and particle size distribution and specific surface area measurements were used to analyze the structure and morphology of the material samples. Their charge-discharge performance and electrochemical impedance spectroscopy were also studied. The results showed that the disorder intensity of amorphous nickel hydroxide is increased, the average particle size is decreased and the specific surface area is also increased by adding rare earth Y, to the benefit of decreasing solution resistance, charge transfer resistance and Warburg impedance for the sample electrodes due to the increase of discharge specific capacity. The discharge specific capacity is 333.3 mAh·g-1 when adding 4% Y (mass fraction) at a charge-discharge system of 0.2 C and a cut-off voltage of 1 V if used for the anode materials of MH-Ni battery