Ultra-sensitive photoelectrochemical sensor for copper ion detection based on ITO/BiVO4 photoelectrode

In this work, a photoelectrochemical sensor for Cu2+ trace detection was prepared based on the excellent semiconductor material BiVO4 modified ITO electrode. It was found that Cu2+ formed a doping effect by adsorption on the surface of ITO/BiVO4 electrode, which inhibited the photogenerated electron complex and thus caused an increase in photocurrent. In addition, due to the complexation effect of EDTA on Cu2+, the Cu2+ 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 mu M and the detection limit was 0.063 pM. The PEC sensor exhibits the advantages of high sensitivity and reusability for Cu2+ detection. This provides a novel PEC detection platform for Cu2+ monitoring in environmental water samples.

Automated summary

In this study, a photoelectrochemical sensor for trace detection of Cu2+ was developed using an ITO electrode modified with BiVO4, a semiconductor material. The adsorption of Cu2+ on the surface of the ITO/BiVO4 electrode led to a doping effect, which inhibited the photogenerated electron complex and increased the photocurrent. Furthermore, the addition of EDTA to the system allowed for desorption of Cu2+ from the electrode surface, resulting in the photocurrent returning to its blank value and enabling electrode reuse.