Facile synthesis of Pt–Pd@Silicon nanostructure as an advanced electrocatalyst for direct methanol fuel cells

Abstract

In this work, platinum–palladium (Pt–Pd) is assembled in-situ on the surface of porous silicon flour (PSiF) through chemical reduction of PtCl62−/PdCl42− and oxidation of the precursor solution SiF64−. The components and the morphological properties of the Pt–Pd on PSiF is investigated by means of transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction techniques. In the next stage, screen printed graphene electrode (SPGE) is prepared by electro-reduction of exfoliated graphene oxide at the surface of a screen printed carbon electrode (SPCE), which is subsequently characterized by FT–IR, Raman spectroscopy, FE-SEM, and electrochemical methods. Finally, a combination of Pt–Pd@PSi nanostructure and SPGE is used for the electro-oxidation of methanol in direct methanol fuel cell. The electrochemical results demonstrate that the Pt–Pd@PSiF–SPGE exhibits an excellent electrocatalytic activity for methanol oxidation. In addition, the electron transfer kinetic of methanol oxidation on Pt–Pd@PSiF–SPGE is investigated by electrochemical impedance spectroscopy. The results showed that the surface of Pt–Pd@PSiF–SPGE is not affected (poisoned) by intermediate products such as CO.