伏安法的谐波和相角研究及其分析应用

项目名称： 伏安法的谐波和相角研究及其分析应用

项目编号： No.21475046

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 王立世

作者单位： 华南理工大学

项目金额： 88万元

中文摘要： 伏安法是一种非常重要而且应用广泛的电化学表征、分析方法。传统的伏安法主要依据氧化还原电位分辨不同物质，然而对于电化学性质十分接近的物质，一直存在选择性差、分辨率低的问题；近来大量研究集中在修饰电极以解决这一问题，但是修饰电极存在制备过程繁琐，测试过程中不稳定的问题。本项目的研究拟利用大振幅正弦伏安法激发电化学体系，对响应电流进行傅里叶变换，采集基次及高次谐波的信号，利用指纹相角信号分辨电化学性质相近的物质。即，对于给定的电化学体系，首先采用傅里叶变换大振幅阶梯正弦伏安法寻找可以实现目标物质与干扰物质的最佳分辨的谐波与相位差，然后在给定的直流电位上叠加大振幅正弦波施加于电化学体系，通过傅里叶变换在最佳的谐波和相位下实验目标物质的高灵敏度检测。本项目拟通过研究构建一套谐波与相位的分析检测技术理论和应用方法，并将其应用于生物物质电化学传感器及液|液界面离子迁移转感器的研究。

中文关键词： “指纹”锁相；大振幅；谐波分析；正弦伏安法；傅立叶变换

英文摘要： Voltammetry is an important and widely used electrochemical characterization and analysis method. Traditionally, the selectivity of voltammetric analysis depends on the difference of redox potentials. However, for the substances with very close electrochemical properties, it hard to achieve selective detection with voltammetry. In order to enhancing the selectivety, previous researches placed much emphasis on modifying electrodes. However,the preparation of the modifyed electrodes is tedious, and during the testing process the working electrode are often instabile. Specifically, we attempt to perturbe the electrochemical system with large-amplitude sinusoidal and the responsive current is subsequently analysis in the fraquency domain by Fourier transform. The selective detection can be realized by quantifying the amplitude of certain harmonic element at the characteristic fingerprint phase angle. that is, for a given electrochemical system, Fourier transform large amplitude step sinusoidal voltammetry were first introduced in for realizing optimum resolution target substance from the interference by harmonic and the phase difference, and then the electrochemical system was perturbed with a large-amplitude sinusoidal potential signal and the responsive current signal was subsequently analyzed in the frequency domain by Fourier transformation . The selective detection can be realized by quantifying the amplitude of a certain harmonic element at the characteristic fingerprint phase angle of each redox couple; and their phase angle difference can be regulated to be close to 90 to eliminate interferences and optimize the selective detection.This project intends to build a harmonic and phase detection technique theory and application method, which will be applied to biological material electrochemical sensor and ionic liquid|liquid interface migration sensor research

英文关键词： Finger-print Phase angle lock-in;Large-amplitude;Harmonic Analysis;Sinusoidal Voltammetry;Fourier Transform