Nano-silicon carbide supported catalysts for PEM fuel cells with high electrochemical stability and improved performance by addition of carbon

Nano-silicon carbide was applied as a novel catalyst support in proton exchange membrane (PEM) fuel cells to improve catalyst stability, due to its excellent resistance to electrochemical oxidation. Homogeneously dispersed Pt nanoparticles were deposited on β-SiC (Pt/SiC) using an ethylene glycol reduction method. Furthermore, carbon was introduced into this Pt/SiC catalyst, (Pt/SiC/C), to improve its electrocatalytic performance by increasing the electrical conductivity. The electrochemical stability of SiC was investigated and showed almost no changes in the redox region after oxidation for 48 h at 1.20 V. Based on accelerated durability tests (ADT) and high-resolution transmission electron microscopy (HRTEM), the electrochemical stability of Pt/SiC/C was remarkably enhanced compared with the Pt/C catalysts, which could be attributed to the excellent stability of the SiC support and the addition of high electrical conductivity carbon.

Figure optionsDownload as PowerPoint slideResearch highlights▶ Silicon carbide (SiC) as an important ceramic widely used in industry fields has an ability to function under extreme conditions and is expected to enable significant improvements to stability of fuel cell catalysts. ▶ The high quality Pt/SiC catalyst was successfully obtained, that in which Pt nanoparticles with an average size of 3 nm are homogeneously dispersed on surfaces of nano-β-SiC ceramics (50 nm in average). ▶ The catalytic activity of catalysts can be greatly enhanced by introducing high electronic conductivity carbon into the Pt/SiC catalyst which has a very high electrochemical stability.