Highly sensitive photoelectrochemical sensor based on MOF (CAU-17)-derived WO3 nanoleaves/BiVO4 nanoparticles heterojunctions for the detection of amoxicillin

The rational construction of semiconductor heterojunctions with abundant active specific area and matched energy band alignment is vital to boosting photocurrent response in highly sensitive photoelectrochemical (PEC) sensors. Here, a molecularly imprinted PEC sensor is proposed based on a WO3/BiVO4 heterojunction using CAU17, a Bi-based metal-organic framework (MOF), as a structural control agent. Unlike the conventional embedding structure, in which WO3 is covered by BiVO4 or vice versa, this MOF-derived WO3/BiVO4 hybrid comprises WO3 nanoleaves and uniformly distributed BiVO4 nanoparticles. This structure offers a comparatively large surface area, enhancing light adsorption and enhancing solid-solid and solid-liquid interfacial contact, thereby promoting photogenerated electron-hole separation, rapid charge transfer, and interfacial reaction. With the aid of molecular imprinting technology, the WO3/BiVO4-based PEC sensor is capable of quantitatively detecting amoxicillin, a frequently prescribed antibiotic in both human and veterinary medicine. This sensor exhibits broad linear range of 10- 3-103 mu mol L- 1, low detection limit of 2.4 x 10-4 mu mol L- 1, high specificity, reproducibility, and stability. Furthermore, it has significant practical potential for environmental pollution monitoring.