Ultrathin BiOCl nanosheet modified TiO2 for the photoelectrochemical sensing of chlorpyrifos

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.