对位叠式循环方波伏安法 Ⅰ.简单可逆电极体系

Checking Potential Additive Cyclic Square Wave Voltammetry I . Simple Reversible Electrode System

本文提出叠式循环方波伏安法和对位叠式循环方波伏安法,对简单可逆电极体系的理论作了推导和验证.经对各种电流的比较,发现对位叠式循环方波伏安法有较多的优点;较之其它方波伏安法灵敏.

This paper presents the additive cyclic square wave voltammetry and checking potential additive cyclic square wave voltammetry (CPACSWV). They can further eliminate the charging current existing in additive square wave voltammetry, and improve the shape of current-potential curve to enhance sensitivity of determination. The theoretical current equations in simple reversible electrode process of these techniques have been derived by the authors, and Ti( Ⅳ )-H2C2O4 system was used to verify the theory. When square wave amplitude (E) is smaller than 20 mV, the voltammogram of unchecking potential additive cyclic square wave voltammetry shows a curve with negative and positive double peaks, but E5≥50 mV, the qurrent curve of it shows an inflection point. In CPACSWV, for a large or a small square wave amplitude, the current response is still a smooth curve with negative and positive double peaks, its peak-to-peak height is higher than that of square wave voltammetry, itsderivative curve shows symmetric peak, and the peak potential of its frist derivative curve is equal to half-wave potential. The sensitivity and resolution in these techniques have shown some improvement. Experimental results consist with the theoretical conclusions.