Preparation of Au nanoparticles modified TiO2/C core/shell nanowire array and its catalytic performance for NaBH4 oxidation

•A novel 3D Au nanoparticles electrode with good electron conductivity and high surface area is successfully fabricated.•Au nanoparticles are uniformly distributed on the surface of C@TiO2 nanowire array.•The electrode exhibits high performance and good stability for NaBH4 oxidation.

In this work, Au nanoparticles directly grown on the surface of TiO2 core-C shell (Au/C@TiO2) has prepared by a simple electrodeposition method for the first time. The morphology is characterized by scanning electron microscope, and its structure is investigated by X-ray diffraction. Au nanoparticles are uniformly distributed on the surface of C@TiO2 nanowire array. Its catalytic performance for NaBH4 oxidation is evaluated by cyclic voltammetry and chronoamperometry measurement. The results indicate that Au/C@TiO2 shows a good and stable catalytic performance. In 2 mol cm−3 NaOH and 0.2 mol cm−3 NaBH4 the oxidation current density for the electrooxidation of BH4− can reach 475 mA cm−2 at 0 V. The electrons transfer number released by BH4− electrooxidation on Au/C@TiO2 electrode has been found to be a 6-electron process. The high performance is mainly attributed to its 3D structure which can promote the mass transport of NaBH4, electronic conductivity and Au utilization.