Construction of Cu2O/TiO2 heterojunction photoelectrodes for photoelectrochemical determination of glucose

Photoelectrodes constructed with photoactive materials are of great significance for the performance of photoelectrochemical (PEC) sensors. In this study, a facile and efficacious non-enzymatic glucose sensor based on the Cu 2 O/TiO 2 heterojunction was successfully constructed for quantitative determination of glucose concentration. The Cu 2 O/TiO 2 heterojunction was generated by first obtaining TiO 2 nanofibers via electrostatic spinning and high-temperature calcination, and then synthesizing Cu 2 O nanoparticles via a one-step hydrothermal reaction. By introducing the narrow band gap semiconductor Cu 2 O, the defect that pure TiO 2 could not absorb visible light was improved, resulting in the improved photoelectrochemical performance of the composite material compared to the single component semiconductor. The sensor exhibited favorable PEC non-enzymatic glucose sensing performance under simulated sunlight irradiation with a wide linear response range from 1 mM to 14 mM (R 2  = 0.9991) and a low detection limit of 14.4 μM (S/N = 3), along with good selectivity, stability and reproducibility. This also provided more ideas and possibilities for preparing photoelectrode materials by constructing heterojunctions.