Effect of platinum-nanodendrite modification on the glucose-sensing properties of a zinc-oxide-nanorod electrode

Highlights: • Effect of PtNDs on ZnONRs/ITO glucose sensor was studied. • Well-defined PtNDs synthesis using 20 mM K₂PtCl₄ produced good dispersion between nanodendrites with uniform particle size. • Nafion coating significantly improved the catalytic oxidation of glucose sensor. • Nafion/GO_x/PtNDs/ZnONRs/ITO demonstrated better properties compared with Nafion/GO_x/PtNDs/ITO and Nafion/GO_x/ZnONRs/ITO electrodes. - Abstract: The properties of ZnO nanorods (ZnONRs) decorated with platinum nanodendrites (PtNDs) were studied. Various sizes of PtNDs were synthesized and spin coated onto ZnONRs, which were grown on indium–titanium–oxide (ITO) substrates through a low-temperature hydrothermal method. Scanning electron microscopy and X-ray diffraction analyses were conducted to analyze the morphology and structural properties of the electrodes. The effects of PtND size, glucose concentration, and Nafion amount on glucose-sensing properties were investigated. The glucose-sensing properties of electrodes with immobilized glucose oxidase (GO_x) were measured using cyclic voltammetry. The bio-electrochemical properties of Nafion/GO_x/42 nm PtNDs/ZnONRs/ITO glucose sensor was observed with linear range within 1–18 mM, with a sensitivity value of 5.85 μA/mM and a limit of detection of 1.56 mM. The results of this study indicate that PtNDs/ZnONRs/ITO has potential in glucose sensor applications.