Facial synthesis of highly efficient non-enzymatic glucose sensor based on vertically aligned Au-ZnO NRs

Abstract

Scheme 1. Schematic illustration of the preparation and fabrication of ZnO NRs on the FTO electrode, followed by Au nanoparticle’s deposition for glucose sensing. Scheme 2. The schematic illustration of conversion of glucose into gluconolactone by using fabricated Au-ZnO NRs electrode. The preparation and fabrication of sensitive non-enzymatic electrochemical sensor based on ZnO NRs grown on the electrode surface by hydrothermal method while maintain the surface morphology of the nanorods was a challenge with high surface area and good sensing capacity. Herein we prepare vertically aligned ZnO NRs on FTO surface and decorated with Au nanoparticles for efficient non-enzymatic glucose sensor. The Au-ZnO NRs were characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Energy Dispersive X-Ray (EDX), and electrochemical methods. The unique hexagonal Au-ZnO NRs possessed high surface area with enhanced electrochemical features for glucose oxidation. The Au-ZnO NRs have excellent linear range up to 15 mM, low detection limit (LOD) of 0.12 μM and high sensitivity of 4416 μA mM −1 cm −2 . The Au-ZnO NRs also possessed good stability, repeatability, selectivity, and reproducibility with practical application for glucose sensing in real samples. The excellent potential of Au nanoparticles decorated on ZnO NRs towards glucose detection provides new platform for fabrication of glucose detecting devices.