(中南大学 冶金科学与工程学院, 长沙 410083)
摘 要: 结合恒电流阶跃和信号处理技术， 用统计直方图和快速傅里叶变换（FFT）对电解槽中电解气泡产生时电极电位的波动信号进行了统计和频谱分析。 采用MatLab语言及其提供的信号处理工具箱构造算法， 获得电位波动在频域上的波形信号， 通过计算功率谱密度PSD随频率的变化， 分析了电解气泡行为特性， 获得平均气泡脱离速率、 气泡脱离的平均直径以及平均气泡体积等特性参数。 研究结果表明：用电位波动的直方图和FFT频谱分析可以获得有关电极表面气泡释放行为的信息， 如气泡脱离时电位波动的平均幅值、平均气泡脱离速率、 气泡脱离的平均直径以及电解气泡平均体积等特性参数， 以用于分析研究电解过程电极界面的气泡行为。
关键字: 电解气泡； 电位波动； 频谱分析； FFT； MatLab
（College of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China）
Abstract:The potential fluctuations observed under current control during gas evolution were analyzed by statistic histogram and FFT spectral analysis. Potential fluctuation signals were processed by means of program coded with MatLab and its signal processing toolbox. Calculated power spectral densities (PSDs) were used to analyze bubble behaviors occurring at a platinum disk microelectrode of 100um and 1 mm in diameter during galvanostatic polarization. Some characteristic parameters of the gas evolution, such as the average number of detached bubbles per time unit, the average radius of detached bubble and the mean volume of bubble, were derived from measured PSD of potential fluctuation. The results show that useful information related to bubble behaviors on interface of electrode/electrolyte can be obtained by histogram and FFT spectral analysis, which can be applied to investigate the electrolytic bubble occurring within electrochemical reactor.
Key words: electrolytic bubble; potential fluctuation; spectral analysis; FFT; MatLab
