虚拟恒电位仪的研制及其在腐蚀电化学测量中的应用

恒电位仪是腐蚀电化学测量最重要的基本设备.虚拟恒电位仪用图形程序软件取代复杂硬件来实现恒电位功能.它的结构和参数灵活,构建简单,能满足多方面腐蚀电化学测试方法的需求,虚拟恒电位仪的实现是发展虚拟腐蚀电化学仪器的重要步骤.本文采用LabVIEW 2010编程系统和比例-积分-微分(PID)控制技术,研制了虚拟恒电位仪,并组建了VEC11-A腐蚀电化学测试系统,该系统能满足不同阻抗体系的腐蚀电化学测试需求.其腐蚀电位、稳态极化曲线、线性极化曲线、循环伏安、动电位扫描、恒电位阶跃等常规腐蚀电化学测量结果与2263电化学测试系统相近,能够满足常规腐蚀电化学测试要求,具有很大的发展空间.     

电化学测试中溶液电阻的自动测量与补偿

由16位DAC器件作为分压器,设计了恒电位仪以及正反馈补偿电路,实现了对溶液电阻的自动测量和补偿,同时采用高阻抗体系对其溶液电阻测量的准确性和补偿效果进行了验证.结果表明,溶液电阻最高补偿值可达1.0×10(8)Ω,在可补偿电阻范围内,自动电阻测量误差最大不超过1.5%,平均误差小于0.5%.本实验设计的电路可以较精确...     

A novel experimental method for potential controlled electrochemical impedance spectroscopy

Abstract  In many cases, impedance spectroscopy on electrochemical systems is performed in combination with a potentiostat. The common way of combining a potentiostat and a frequency response analyzer has a number of restrictions. Bandwidth limitations and artifacts from the setup distort the impedance data in sometimes unpredictable manners, and special care has to be taken in physical interpretation of such data. Therefore, potential controlled measurement of artifact-free impedance spectra in a wide range of frequencies is desirable. In this work, a novel experimental method is presented in which the more reliable two-probe impedance spectroscopy is combined with a potential control by a potentiostat without interfering each other. Results obtained on passive zinc by two-probe EIS, the classical potentiostat—EIS combination and the new setup are compared with each other. For an application of the proposed method in measurements of solid state systems, the specific problems are discussed. Graphical abstract        

Elektrochrome Fenster mit leitenden Polymeren

The construction of a low‐cost potentiostat and an electrochemical cell are described. Both have been used for the potentiostatic deposition of conducting polymers on FTO‐coated glass. According to a reported procedure from literature an electrochromic window has been prepared and tested. Furthermore a novel window containing an additional electrodeposited polymer layer that shows a more pronounced electrochromism than the literature example is described for the first time. The required chemicals are inexpensive as well as the entire electrochemical equipment.