BiVO ₄ @Ce–BDC–NH ₂ nanocomposite based on VO ₄ vacancy and heterostructures for electrochemical detection of metol

Abstract We develop a highly active electrocatalyst composite based on BiVO ₄ @Ce–BDC–NH ₂ (B(VO) _1−δ @CeBN) nanocomposite including VO ₄ vacancies ((VO) _{1− δ} ) and heterojunction comprising bismuth vanadate (BiVO ₄ ) and a cerium-based metal–organic framework (Ce–BDC–NH ₂ ) for the ultrasensitive electrochemical detection of organic pollutant metol. The structural and compositional characteristics of B(VO) _{1− δ} @CeBN nanocomposite are analyzed by various microscopic and spectroscopic techniques, and confirmed that forming of the (VO) _{1− δ} defect and heterojunction structures. Furthermore, the B(VO) _{1− δ} @CeBN nanocomposite modified screen printed carbon electrode (B(VO) _{1− δ} @CeBN/SPCE) with exhibited enhanced electrochemical response toward metol including limit of detection of 1.15 nM in a broad linear range of 0.01–1000 µ M as well as a remarkable sensitivity of 0.2692 μ A · μ M ⁻¹ · cm ⁻² . This excellent detection sensitivity arises from the synergistic effect of heterojunction structures constructed between B(VO) _{1− δ} and Ce–BDC–NH ₂ , while VO ₄ vacancies defect enhances charge carrier concentration and conductivity. Additionally, B(VO) _{1− δ} @CeBN/SPCE sensor displays remarkable repeatability, reproducibility, stability, and selectivity toward metol detection. Finally, this work investigated the real-time practicability of metol over the B(VO) _{1− δ} @CeBN/SPCE electrode to detect spiked tape water, with good recovery ranges of 97.7%–98.6% achieved. These results highlight the potential of B(VO) _{1− δ} @CeBN/SPCE as a promising nanoplatform for trace-level detection of organic pollutants in environmental water bodies.