Carbon-Supported Platinum Molybdenum Electro-Catalysts and Their Electro-Activity Toward Ethanol Oxidation

Abstract

We synthesized and studied a series of carbon-supported PtMo catalysts with a 20% metal loading as active phase. The analysis was made with three atomic ratios in the active phase, Pt-Mo: 1-1, 7-3 and 3-1. Samples were prepared by reducing metal precursor salts with formic acid. The materials were electrochemically characterized by cyclic voltammetry, current–sampled voltammetry, CO stripping voltammetry and electrochemical impedance spectroscopy. Physical characterizations were carried out by means of SEM-EDX and DRX. EDX analysis show that the atomic proportion between Pt and Mo is similar to the nominally proposed. DRX analysis allowed the identification of metallic Pt and different Mo oxides. The calculated average crystallite size was 4.7 nm. Electrochemical analysis revealed that the sample Pt-Mo 7:3 improves the catalytic activity of the anodic ethanol oxidation reaction, increasing the current density with low Pt loading and reducing the exchange charge resistance.