Pd doped three-dimensional porous Ni film supported on Ni foam and its high performance toward NaBH4 electrooxidation

Abstract

A novel three-dimensional electrode consisting of Pd doped porous Ni film supported on Ni foam (Pd-porous Ni/Ni) is successfully prepared. The porous Ni film is synthesized by electrodeposition of Ni nanoparticles using hydrogen bubbles as a dynamic template. Pd doping is carried out via a chemical replacement reaction between Ni film and Na2PdCl4 solution. The obtained electrode exhibits a three-dimensional (3D) porous structure allowing the full utilization of catalyst surface active sites. The morphology of the electrode and the distribution of Pd on Ni particle surfaces are characterized by scanning electron microscope and energy dispersive X-ray spectrometer. The structure is analyzed using an X-ray diffractometer. The catalytic performance of the porous 3D electrode is evaluated by voltammetry and chronoamperometry. Results show that the electrode displays high catalytic activity and good stability for NaBH4 electrooxidation. The oxidation current density of NaBH4 on the Pd-porous Ni/Ni in 3.0 mol L−1 NaOH containing 0.1 mol L−1 NaBH4 at −0.6 V reaches 2.2 A mg−1, which is about 22 times of that on Pd/C (0.1 A mg−1) reported previously.