Studying the effect of pH optimization on the performance of copper oxide electrodes for glucose sensor applications

This study aims to enhance the performance of non-enzymatic glucose sensors by optimizing the pH during the fabrication of copper oxide (CuO) electrodes. The electrodes were synthesized using the chemical bath deposition technique at two different pH values (10 and 12), and their structural and electrochemical properties were analyzed using XRD, SEM, AFM, FTIR, and PL techniques. The results showed that the electrode fabricated at pH 10 exhibited a high sensitivity of 21.488 mA mM⁻1 cm⁻2 and a low detection limit of 1.1 mM, compared to the pH 12 electrode, which had a lower sensitivity of 2.8771 mA mM⁻1 cm⁻2 and a higher detection limit of 14.2 mM. SEM analysis revealed that the pH 10 electrode had particle sizes ranging from 34.34 to 59.53 nm, whereas the pH 12 electrode had slightly smaller particles ranging from 31.66 to 53.31 nm, with a more uniform distribution. AFM analysis showed that the surface roughness was 41.47 nm for the pH 10 electrode and 209.5 nm for the pH 12 electrode, indicating significant differences in surface morphology. These findings demonstrate that controlling the fabrication pH is an effective strategy to improve the performance of non-enzymatic sensors, making them a promising alternative to conventional enzymatic sensors in terms of efficiency, stability, and cost-effectiveness. Graphical abstract