Fabrication of Pt-ZnO composite nanotube modified electrodes for the detection of H2O2

Pt-ZnO nano tubes were synthesized by one-pot electrospinning polyacrylonitrile (PAN) and polyvinyl pyrrolidone (PVP) bipolymer in the presence of zinc acetate and chloroplatinic acid, followed by the calcination of nanofibers. The tubular structure of Pt-ZnO composite and the homogeneous distribution of Pt nanoparticles were confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) characterization demonstrates that ZnO exhibits the hexagonal wurtzite structure, while Pt particles exist mainly in the form of cubic Pt. Zero valence Pt is confirmed by X-ray photo spectroscopy (XPS). Pt-ZnO drop-coated glassy carbon electrode (Pt-ZnO/GCE) was employed for the measurement of H2O2. The Pt/Zn molar ratio affects the catalytic activity to H2O2 reduction. Pt-ZnO/GCE with the Pt/Zn ratio of 1:3 displayed the best catalytic performance, and a corresponding linear relationship was obtained with H2O2 concentrations ranging from 2 x 10(-5)M to 5 x 10(-3) M (R-2 = 0.9969). The limit of detection is 1.5 x 10(-6)M (S/N >= 3). The electrospun-based Pt-ZnO nanotubes have a great potential for electrochemical sensing.