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 Cu2O/TiO2 heterojunction was successfully constructed for quantitative determination of glucose concentration. The Cu2O/TiO2 heterojunction was generated by first obtaining TiO2 nanofibers via electrostatic spinning and high-temperature calcination, and then synthesizing Cu2O nanoparticles via a one-step hydrothermal reaction. By introducing the narrow band gap semiconductor Cu2O, the defect that pure TiO2 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 14mM (R-2 = 0.9991) and a low detection limit of 14.4 mu M (S/N = 3), along with good selectivity, stability and reproducibility. This also provided more ideas and possibilities for preparing photoelectrode materials by constructing heterojunctions.