Non-Enzymatic Photoelectrochemical Sensor Based on rGO/NiCo2O4/ZnO for Glucose Detection

In this article, a photoelectrochemical glucose sensor with a low detection limit, high sensitivity, and easy fabrication was constructed. Nickel cobalt oxide (NiCo ₂ O ₄ ) nanorods and zinc oxide (ZnO) nanorods were grown on foam nickel (NF) by a simple hydrothermal method, and reduced graphene oxide (rGO) was attached. The composite nanomaterials grown on the electrodes were observed by SEM and TEM characterization. The electrode was found to have a good linear range and detection limit of $0.5~\mu \text{M}$ ( ${S}/{N}$ = 3) with low response time (< 3 s) for glucose under the irradiation of a UV lamp at 365 nm by electrochemical workstation with amperometry. The experimental results showed that the sensitivity of the designed sensor electrode for glucose was $5456.99~\mu \text{A}~\cdot $ mM $^{-{1}}\,\,\cdot $ cm $^{-{1}}$ in the range of 0.5– $483.2~\mu \text{M}$ with the correlation coefficient ${R}^{{2}}$ = 0.99628, and $4538.2~\mu \text{A}~\cdot $ mM $^{-{1}}\,\,\cdot $ cm $^{-{1}}$ in the range of $483.2~\mu \text{M}$ –6.9425 mM with the correlation coefficient ${R}^{{2}} = 0.99026$ . In addition to this, the sensor has good resistance to interference, stability, and repeatability, indicating great application value for photoelectrochemical non-enzymatic detecting of glucose.