Rapid synthesis of vertically-aligned zinc oxide nanorods on stainless steel for non-enzymatic glucose and H2O2 photoelectrochemical sensor

A simple and rapid microwave-assisted hydrothermal method is reported to grow vertically-aligned zinc oxide nanorods on stainless steel foil (ZnO@SS NRs) by common household microwave oven in this work. The morphology, microstructure and property of ZnO@SS NRs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy and electrochemical measurement. While the repeated heating times and concentration increased, the ZnO nanorods were formed with higher density. During hydrothermal growth of the ZnO materials, ZnCr2O4 and ZnFe2O4 were found in the ZnO nanorods which showed extended absorption in the visible light region. According to photocurrent measurements, the ZnO@SS NRs photoelectrodes prepared by the concentration of 0.05 M with repeated 8 times shows highest current density, which could be used as a photoelectrochemical (PEC) sensor. The ZnO@SS NRs was applied as a PEC sensor to detect glucose and H2O2 under visible light irradiation. This PEC sensor shows high photosensity to glucose and H2O2 with wide linear range(2–100 μM and 0.1–100 μM, respectively) and low detection limit (3.14 and 0.27 μM, respectively), while the PEC sensor doesn't response to the change of glucose and H2O2 concentration without light irradiation.