A Ti-coated nano-SiC supported platinum electrocatalyst for improved activity and durability in direct methanol fuel cells

Abstract

Nano-silicon carbide (nano-SiC) particles modified with a titanium (Ti) coating were used as a novel support for the platinum (Pt) electrocatalyst in direct methanol fuel cells. Ti-coated nano-SiC (Ti/SiC) powder was prepared by a one-pot deposition method under vacuum and a coating was formed on the nano-SiC surface. The Ti coating was strongly bonded with nano-SiC with the help of TiC and Ti₅Si₃. The Ti/SiC supported Pt electrocatalyst (Pt–Ti/SiC) was fabricated using a microwave-assisted reduction method. The electrocatalytic performances of the Pt–Ti/SiC for the methanol oxidation and oxygen reduction reactions were much higher than the Pt supported on the pristine nano-SiC. The electrochemical stability of the Pt–Ti/SiC was more outstanding compared with the Pt supported on Vulcan XC-72 carbon black. The superior electrocatalytic performance of the Pt–Ti/SiC can be ascribed to the anchoring effect of the Ti coating on Pt nanoparticles and the high stability of the nano-SiC support.