Pt electrodeposited on CeZrO<inf>4</inf>/MCNT as a new alternative catalyst for enhancement of ethanol oxidation

Abstract

Electrocatalytic preparation of Pt-based nanocomposites has been investigated for improvement of direct ethanol fuel cells (DEFCs). In this study, new alternative catalysts of Pt-decorated cerium zirconium oxide-modified multiwalled carbon nanotubes (Pt/CeZrO4/MCNT) were successively prepared to improve the activity of the ethanol oxidation reaction (EOR). The prepared CeZrO4 with a face-centered cubic (fcc) structure compatibly dispersed onto MCNT provides abundant active Pt sites for highly active catalysts. The fcc-structured Pt was also satisfactorily decorated onto CeZrO4/MCNT, resulting in highly active Pt. The Ce4+/Ce3+ redox property can promote oxygen vacancies to improve the electrochemical activity for oxidation of carbonaceous species. An increase in roughness and a stabilized catalyst structure can also be produced by inserting Zr4+ into the ceria metal oxide. The prepared Pt/20%CeZrO4/MCNT catalysts present excellent electrochemical active surface area, mass activity, CO tolerance and high electron kinetic transfer with low resistance and high stability over commercial PtRu/C toward EOR. This promising catalyst material could be introduced to enhance the anodic oxidation reaction in DEFCs.