Lu Min, Compton Richard G
Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QZ, UK.
Analyst. 2014 May 21;139(10):2397-403. doi: 10.1039/c4an00147h.
A simple sensor for pH determination is reported using unmodified edge plane pyrolytic graphite (EPPG) electrodes. The analysis is based on the electro-reduction of surface quinone groups on the EPPG which was characterised using cyclic voltammetry (CV) and optimised with square-wave voltammetry (SWV). Under optimised conditions, a linear response is observed between the peak potential and pH with a gradient of ∼59 mV per pH (at 25 °C), which corresponds well with Nernstian behaviour based on a 2 proton, 2 electron system over the aqueous pH range 1.0 to 13.0. As such, an EPPG is suggested as a reagent free and robust pH sensing material.
报道了一种使用未修饰的边缘平面热解石墨（EPPG）电极测定pH的简单传感器。该分析基于EPPG表面醌基团的电还原，通过循环伏安法（CV）对其进行表征，并采用方波伏安法（SWV）进行优化。在优化条件下，观察到峰电位与pH之间呈线性响应，梯度约为每pH 59 mV（25°C时），这与基于2个质子、2个电子系统在1.0至13.0的水溶液pH范围内的能斯特行为非常吻合。因此，EPPG被认为是一种无需试剂且坚固耐用的pH传感材料。
