Ultrathin BiOCl nanosheet modified TiO2 for the photoelectrochemical sensing of chlorpyrifos

Abstract

A convenient photoelectrochemical sensor was constructed based on the synergistic contributions of an ultrathin BiOCl nanosheet and anchored TiO₂ nanoparticles to detect the organophosphorus pesticide chlorpyrifos. As expected, the fabricated heterostructure showed a distinct improvement in photocurrent intensity compared with pristine BiOCl and TiO₂. This remarkable enhancement may be attributed to the separation and transfer of photogenerated charge carries, which benefit from intimate interfacial interactions between the ultrathin BiOCl nanosheets and TiO₂ nanoparticles. Based on the robust photocurrent signal, a novel PEC sensor was established for the sensitive and selective detection of chlorpyrifos. The as-fabricated PEC sensor demonstrates many advantages such as a wide linear range of 1–12 μM, a low detection limit of 0.11 μM, S/N = 3, and remarkable convenience, which provides a general format for chlorpyrifos detection in green vegetable analysis.