A visible-light-driven photoelectrochemical sensing platform based on the BiVO4/FeOOH photoanode for dopamine detection

Photoelectrochemical (PEC) analysis technique provides a unique route for sensitive biomolecular detection. In this paper, a novel visible-light-driven PEC sensor for detection of dopamine (DA) was fabricated based on ultrathin FeOOH cocatalyst modified nanoporous BiVO 4 photoanode. Scanning electrochemical microscopy (SECM) technique was employed to characterize the photocatalytic activities of the as-prepared photoanodes surfaces, and the first-order heterogenous electron transfer rate constants ( K eff ) were evaluated, which further revealed the photocatalytic performance of the modified photoanodes in water oxidation and the PEC sensing mechanism. A remarkable water oxidation photocurrent on the ITO/BiVO 4 /FeOOH photoanode could be achieved and served as anodic photocurrent of blank sample for PEC sensing dopamine (DA), which showed linearly range of 0.2–40 μM and 40–1400 μM with a detection limit of 0.09 μM. This method showed simplicity, high sensitivity and selectivity, high stability and wide linearity range, which provided a promising platform for the development of PEC sensor and offered an insight into the exploitation of BiVO 4 -based photolysis water materials for PEC bioanalytical purposes.