Abstract

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 CAU-17, 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 μmol L^?1, low detection limit of 2.4×10^?4 μmol L^?1, high specificity, reproducibility, and stability. Furthermore, it has significant practical potential for environmental pollution monitoring.