Advanced synthesis of highly stable and scalable porous Mo–BiVO4 thin film: A robust platform for non-enzymatic photoelectrochemical sensing of redox-active biomolecules

A scalable fabrication route via hot spin coating (HSC) was employed to prepare mesoporous Mo-doped BiVO 4 (Mo–BiVO 4 ) thin-film photoelectrodes for an enzyme-free PEC glucose sensor. Under optimized conditions (Tris buffer, pH 9, applied bias 0.15 V), the sensing device exhibited a broad linear response (0.1 to 200 μM) with a detection limit of 45 nM. High anti-interference ability was observed, while the sensor performance was successfully validated in human serum and urine matrices. Notably, the fabricated PEC sensor preserved ∼80% of the initial photoresponse upon 60 consecutive measurement cycles over 90 days period. Strong interfacial adhesion between Mo–BiVO 4 and indium tin oxide (ITO) substrate achieved by HSC is responsible for such exceptional durability reducing the costs associated with replacing diagnostic kits (around 75% reduction compared to the average price of benchmark disposable glucose test strips). The combination of high durability, facile and scalable fabrication, and enzyme-free operation highlights the potential of this PEC platform toward developing economical and sustainable sensing platforms for precise and frequent monitoring of redox-active biomolecule in clinical and research environments.