Facile Preparation of Pt/Polyallylamine/Reduced Graphene Oxide Composites and Their Application in the Electrochemical Catalysis on Methanol Oxidation

摘要

In this article, a facile synthesis of Pt/polyallylamine/reduced graphene oxide (Pt/PAA/RGO)composites is put forward by using PAA as a linker and stabilizer, which is characterized by ultravioletvisible absorption, fourier transform infrared spectroscopy, thermogravimetric analysis, X-rayPhotoelectron Spectroscopy and transmission electron microscopy. In the presence of PAA, Ptnanoparticles with an average diameter of 1.4 nm are uniformly dispersed on RGO. In contrast, as toPt/RGO prepared without PAA, Pt nanoparticles averaged 4 nm are unevenly deposited andaggregated on RGO. Pt/PAA/RGO composites exhibit a higher conversion efficiency of methanol anda faster oxidation removal of adsorbed CO during the electrochemical catalysis process due to theirgreater electroactive surface area. The molecular pathway of methanol oxidation at the surface of Ptcatalysts is revealed in the impedance measurements. The impedance response of Pt/PAA/RGOcatalysts shows a capacitive, resistive, pseudoinductive or inductive behavior depending on the appliedpotential.