The electrochemical detection of 4-chlorophenol at gold electrodes modified with different phthalocyanines

Because of their toxicity to humans and their tendency to bioaccumulate in the food chain, the detection of chlorophenols has been investigated intensively. This paper compares the oxidation of 4-chlorophenol on a bare gold electrode to its detection on gold electrodes electrochemically modified with either cobalt(II) tetrasulphonated phthalocyanine (CoTSPc) or 3,4′,4″,4‴-copper(II) tetrasulphonated phthalocyanine (CuTSPc). Results show that the electrochemical behaviour of 4-chlorophenol depends on the molecular structure of the phthalocyanine thin film layers on the gold surface. In addition, the influence of the coordinating properties of the phthalocyanines on the sensitivity of the measurement and the fouling of the electrode material is discussed.