Synthesis of 3D Flower-Like Ni0.6Zn0.4O Microspheres for Electrocatalytic Oxidation of Methanol

The 3D flower-like Ni0.6Zn0.4O microspheres were prepared by calcination treatment of Ni-Zn LDHs (layered double hydroxides) that were obtained through a hydrothermal method. The yielded Ni0.6Zn0.4O microspheres were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET). The results showed that the calcinated microspheres of Ni0.6Zn0.4O still well maintained the flower-like architecture of Ni-Zn LDHs. The surface area, total pore volume, and average pore diameter of the Ni0.6Zn0.4O microspheres were obtained with the values of 36.106 m(2) g(-1), 0.111 cm(3) g(-1), and 5.676 nm, respectively. As modified anode active materials, the Ni0.6Zn0.4O microspheres exhibited excellent electrocatalytic performance and fast electrochemical kinetics for methanol oxidation in strong alkaline electrolyte where the high surface area of flower-like Ni0.6Zn0.4O microspheres provides the high contact probability between catalysts and reactants. The presence of Zn also improves the electron transfer within catalysts inside. Also, the Ni0.6Zn0.4O modified electrode maintained good electrocatalytic performance during the term of 36,000 s.