Ultra-sensitive photoelectrochemical sensor for copper ion detection based on ITO/BiVO photoelectrode.

In this work, a photoelectrochemical sensor for Cu trace detection was prepared based on the excellent semiconductor material BiVO modified ITO electrode. It was found that Cu formed a doping effect by adsorption on the surface of ITO/BiVO electrode, which inhibited the photogenerated electron complex and thus caused an increase in photocurrent. In addition, due to the complexation effect of EDTA on Cu, the Cu adsorbed on the electrode surface is desorbed and the photocurrent returns to the blank value, making it possible to reuse electrodes. Under optimal conditions, the linearity range was measured between 0.1 pM and 0.1 μM and the detection limit was 0.063 pM. The PEC sensor exhibits the advantages of high sensitivity and reusability for Cu detection. This provides a novel PEC detection platform for Cu monitoring in environmental water samples.