Silica template as a morphology-controlling agent for deposition of platinum nanostructure on 3D-Ni-foam and its superio

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Silica template as a morphology‑controlling agent for deposition of platinum nanostructure on 3D‑Ni‑foam and its superior electrocatalytic performance towards methanol oxidation Mohammad Ali Kamyabi1 · Kajal Ebrahimi‑Qaratapeh1 · Mohsen Moharramnezhad1 Accepted: 20 October 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract In this work, a novel sponge-like platinum nanostructures are fabricated on a nickel foam and utilized for electro-oxidation of methanol. The fabrication method consisted of three steps: the electrodeposition of mesoporous silica film onto the Nifoam as a template, the galvanic replacement of Pt nanostructures into the silica-templates/Ni-foam, and finally removing the silica templates. The silica templates were used as a morphology regulating agent to modify the electrode with sponge-like platinum nanostructures. Physical characterization of the modified electrodes was performed by electrochemical impedance spectroscopy, field emission scanning electron microscopy, energy dispersive X-Ray, and X-Ray diffraction analysis. The electrochemical experiments present high electron transfer kinetics, high CO tolerance ability, and superior stability for sponge-like Pt/Ni-foam towards methanol electro-oxidation in the acidic medium. The easy and low-cost construction process and robust electrochemical performance of the proposed catalyst opens a new pathway as the new shape of the platinum nanomaterials for the anode of the direct methanol fuel cell. Keywords  Sponge-like pt nanostructures · Galvanic replacement · Nickel foam · Silica template · Methanol electrooxidation

1 Introduction One of the major issues that mankind has faced from the outset as the main challenge is the energy crisis, the completion of fossil fuels, and environmental pollution. Therefore, it is essential to pursue innovative and efficient methods to convert fuel energy into usable energy. In direct alcohol fuel cells (DAFCs), chemical energy is converted into electrical energy [1]. Methanol has been raised as one of the best fuel for DAFCs due to its liquidity at ambient temperature, facile storage, its easy preparation from natural gas, and low operation temperature. However, the electron transfer rate Electronic supplementary material  The online version of this article (https​://doi.org/10.1007/s1093​4-020-01001​-z) contains supplementary material, which is available to authorized users. * Mohammad Ali Kamyabi [email protected] 1



Electroanalytical Chemistry Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, 45371‑38791 Zanjan, Iran

of methanol oxidation reaction (MOR) is slow, owing to the anode poisoning phenomenon. In this aspect, some intermediates such as CO and OH species are adsorbed on the catalyst surface and obstruct the active sites for methanol oxidation [2, 3]. Hence, modification of anodes in methanol fuel cells with high durability toward poisoning species has possessed the attention of many researchers in the last decades [4–7]. Due to the high c