Synthesis, Characterization And Electrocatalytic Performance Of Graphene Supported Pt-based Anode Catalysts For Direct Methanol Fuel Cells

The catalytic activity and stability of catalyst seriously restricts the performance of direct methanol fuel cells (DMFCs). DMFC is one of the proton exchange membrane fuel cell, because its many advantages are widely studied in recent years. So far, Pt nanocomposites have been widely used as anode catalyst for DMFC. To Prepare the high catalytic stability and catalytic activity of the anode catalyst materials is the hotspot research of DMFC recently. A variety of new types of graphene loading the Pt anode catalyst for DMFC have been produced in this paper and research their electrochemical properties and stability in detail. The research content includes the following three aspects:1. Pt/TMPyP/graphene catalyst have been prepared using the TMPyP functionalized graphene oxide as supported materials via a sodium borohydride reduction process. The obtained Pt/TMPyP/graphene catalyst were characterized by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray Photoclectron Spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Electrochemical results revealed that the Pt/TMPyP/graphene catalyst showed excellent electrocatalytic activity and stability toward methanol oxidation reaction.2. A conducting polymer polyaniline (PANI) is used to form a uniform coating layer over graphene oxide (GO) by liquid-liquid (L/L) interface polymerization method. Thermal annealing of the polyaniline-modified graphene oxide (PANI/GO) nanocomposites in an inert environment leads to removal of oxygenated groups from GO and simultaneous nitrogen doping in the final product, forming NG. Subsequently, loading of Pt NPs on NGs is performed by a chemical reduction method using the doped nitrogen as anchoring sites. Electrochemical results revealed that the Pt/NGs nanocomposites showed excellent electrocatalytic activity and stability toward methanol oxidation and oxygen reduction reaction.3. A simple and facile method is developed to fabricate PtMn bimetallic nanoflower on the surface of PDDA functionalized graphene via NaBH4reduction process. The obtained PtMn/PDDA/graphene nanoflower were characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectrometer (EDX). Electrochemical results revealed that the PtMn/graphene nanoflower catalyst showed excellent electrocatalytic activity and electrocatalytic stability toward methanol oxidation reaction.