Prussian blue/ superactivated carbon composite-modified electrode for detection of p-phenylenediamine

Abstract

A novel approach for the selective determination of p-phenylenediamine in aqueous solution using Prussian blue (PB)/ superactivated carbon (SAC) composite-modified glassy carbon electrodes is reported. The chemical constitution and microstructure of PB/SAC composites are studied by SEM, BET and IR data. Due to its unique structure and properties originating from Prussian blue in the superactivated carbon frame, PB/SAC composites show high electrocatalytic activity towards the oxidation of p-phenylenediamine. A special chemical reaction and electron transfer process on the surface of PB/SAC composite-modified GC electrode is proposed and evaluated by cyclic voltammetry and AC impedance in the presence of p-phenylenediamine. The current value of differential pulse voltammetry increases linearly with the p-phenylenediamine concentration in the range 2×10^-7−1×10^-3 M with a detection limit of 6.47×10^-8 M (S/N = 3). The relative standard deviation of the waste water samples is < 6% and the recovery rate is 97−104%. These results suggest that the modified electrode has high selection for p-phenylenediamine, good repeatability, and operational stability. The modified electrode has been successfully used to analyze the amount of p-phenylenediamine in water samples.