Glucose detection via photoelectrochemical sensitivity of 3D CuO-TiO2 heterojunction nanotubes/Ti combined with chemometric tools.

High sensitivity and low detection limit under visible light for glucose were obtained on CuO-TiO 2 NTs/Ti PEC photoelectrode due to the existence of CuO-TiO 2 heterojunction with 3D macroporous structure, 1D nanotubular structure of TiO 2 , and conductive substrate of titanium foil. Associated with chemometric tools, the accuracy of the sensor was further improved. [Display omitted] • 3D CuO-TiO 2 Heterojunction Nanotubes/Ti exhibit good PEC sensitivity for glucose. • PEC sensing mechanism of CuO-TiO 2 NTs/Ti for glucose was illuminated. • Combining with chemometric tools, sensitive and trustworthy PEC sensor was obtained. High sensitivity and low detection limit are important targets for biosensors. Using 3D hydrogen titanate nanotubes/Ti as precursor, CuO-TiO 2 heterojunction nanotubes/Ti (CuO-TiO 2 NTs/Ti) photoelectrode was prepared to fabricate photoelectrochemical (PEC) glucose sensor. The prominent Ti foil substrate, 3D mesoporous structure, and CuO-TiO 2 heterojunction of this PEC sensor can effectively improve the separation efficiency of charge carriers, facilitate electron transfer, and generate strong photoelectronic signals. Under visible light irradiation, the CuO-TiO 2 NTs/Ti electrode exhibited high sensitivity, low LOD, and good selectivity. Through density functional theory simulation, the enhanced electron-hole separation and improved PEC properties were illuminated in the CuO-TiO 2 heterojunction. Associated with chemometric tools, the accuracy of the sensitivity was significantly improved, which could enhance the practical application capability of PEC biosensors. [ABSTRACT FROM AUTHOR]