(1. 浙江大学 材料科学与工程系, 杭州 310027;
2. 哈尔滨工程大学 化学工程系, 哈尔滨 150001)
摘 要: 应用电化学交流阻抗法(EIS)研究了不同荷电状态下的αNi(OH)2 的质子扩散系数(使用Equivcrt软件拟合实验数据)。结果表明, 质子扩散系数是电极荷电状态的函数, 在荷电状态为20%左右时,质子扩散系数具有最大值, 并且在荷电状态大于10%时, 均大于 β Ni(OH)2 活性物质。 在电极荷电状态为0%时, 阻抗谱为半圆(在频率小于10 Hz时), 未显示固相有限扩散控制的特征。 从理论上讨论了此结果。
关键字: 电化学;交流阻抗谱;电极;氢氧化镍;电池
(1. Department of Materials Science and Engineering,Zhejiang University, Hangzhou 310027, P.R.China
2. Department of Chemistry, Harbin Engineering University,Harbin 150001, P.R.China)
Abstract:The electrochemical AC impedance spectrogram (EIS) was used for studying the proton diffusion coefficients (PDC) of α Ni (OH)2 with various charges. The results show that PDC is a function of chargeofstate. When the stateofcharge is about 20%, PDC has the biggest value, and at>10% of stateofcharge, the PDC for αNi (OH)2 is bigger than β Ni(OH)2. At 0% of stateofcharge a semicircle appears (<10 Hz), EIS does not display the solidphase limited diffusion characteristic. This result has beentheoretically discussed.
Key words: AC impedance spectrogram; electrode; Ni(OH)2; battery