Non-enzymatic photoelectrochemical sensors based on rGO/TiO2/Cu-MOFs nanostructures for simultaneous detection of glucose and lactic acid

Abstract

This study reports the preparation of a high-performance rGO/TiO₂/Cu-MOFs sensitive electrode through a two-step hydrothermal method. This electrode exhibits low detection limits, high sensitivity, and a straightforward fabrication process. The nanomaterials are uniformly grown on a 1 × 1 cm² nickel foam substrate, with rGO first coated and then followed by the growth of rod-shaped TiO₂ and Cu-MOFs metal particles, forming a three-dimensional spatial structure. The micromorphology, chemical composition, and state of the electrode were characterized using TEM, SEM, and other techniques. Its electrochemical performance was tested using an electrochemical workstation. Experimental results indicate that the copper ions in this electrode, due to their different valence states, can achieve highly sensitive detection of glucose and lactic acid, with sensitivities reaching as high as 1195.13 μA mM⁻¹ cm⁻² and 1157.77 μA mM⁻¹ cm⁻², respectively. Additionally, it possesses excellent anti-interference ability, stability, and reproducibility, making it a promising dual-function photoelectrochemical sensor.