镉离子选择电极交流阻抗谱研究——载流子传输活化能和响应机制

Study on the A.C.Impedance Spectra of Cadmium Selective Electrode——Transfer Activation Energy of Charge Carriers and Response Mechanism

六十年代末期以来,离子选择电极的研制和应用得到了迅速的发展,构成了化学传感器的一个重要和基本的类别.与此同时,各国学者对其响应机制进行了多方面探讨.应用交流阻抗测试技术所进行的理论研究也取得了相应的进展.

The A.C.impedance spectra of cadmium selective electrode based on pressedmembrane of crystalline CdS/Ag2S with different composition has been detected usingEG&G PAR 5204 amplifier at different temperatures.Nyquist plot has been done afterdata analysis based on curve fitting.Bulk impedance of membrane of 20℃,30℃,40℃was found from the Nyquist plots.Transfer activation energy Ea of membrane wascalculated based on the theory of solid electrolyte.Effect of membrane composition onEa was studied.Mechanism of charge carrier transport within electrode membrane was predicted.