Synthesis of Core-Shell Co@Pt/C Electrocatalyst and Effects of Stabilizer and pH on Its Performance

Abstract

Carbon-supported Co@Pt core shell catalysts have been synthesized by the two-step chemical reduction method. The effects of the catalyst preparation conditions including pH value of the initial solution and the stabilizers on the performance of the Co@Pt/C catalyst were investigated. Transmission Electron Microscope (TEM) and X-Ray Diffraction (XRD) techniques were used to characterize the nano-structured catalysts. The electrochemical performance of the as-prepared catalyst was characterized by cyclic voltammograms (CV) and liner sweep voltammogram (LSV) techniques. Additionally, the performance of the catalyst was evaluated by a test in single fuel cell. The results showed that the pH value and stabilizers not only significantly influenced the Co@Pt metal morphology property, but also the electrochemical and single cell performance. The proper pH value for preparation was 12, which might be due to that the pH condition would change the charge of the carbon black surface and higher pH value would be beneficial to the metal particles deposition on the surface of carbon support and form the highly dispersed catalyst. The different hydrophobic reaction, dimensional effect and particle interactions are caused by stabilizers. The evaluation of the fuel cell also proved that the optimization of the preparation was helpful to enhance the catalytic performance.