Study on Photoelectrochemical Glucose Sensor Based on Bismuth Vanadate Semiconductor

Determination of glucose is critical in the fields of food industry, pharmaceutical industry and environmental monitoring. Thus it holds great promise to develop a glucose sensor with high sensitivity, good selectivity and low cost. The intrinsic property of separated excitation and detection system of photoelectrochemical method leads the photoelectrochemical sensor to have the potential for the glucose detection with high sensitivity. The BiVO₄ films were prepared on the fluorine-doped SnO₂ (FTO) substrate by a two-step procedure involving an electro-deposition and annealing treatment. X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) were employed to evaluate the structure and the morphology of BiVO₄ films. The results indicated that the obtained BiVO₄ electrode can be assigned to monoclinic phase, with the morphology of aggregated nanoparticles. Furthermore, the BiVO₄ based photoelectrochemical glucose sensor was constructed. The oxidation photocurrent of the sensor displayed a good linear relationship with the glucose concentration in the range of 5~35 mmol/L, and the detection sensitivity was estimated to be 17.38 μA/cm²/(mmol/L). The study provided a novel, simple and cost-effective strategy for the glucose detection.