Electrocatalytic activity of bimetallic PtPd on cerium oxide-modified carbon nanotube for oxidation of alcohol and formic acid

Abstract

This paper proposes an approach for the fabrication of an anode electrocatalyst for application as a fuel cell catalyst. It comprises three components, multiwall carbon nanotube (CNT), ceria oxide (CeO2), and metal (i.e., Pt and/or Pd), using the reduction method for preparation. The characterization of the prepared catalysts was determined by transmission electron microscopy (TEM), X-ray diffraction, and Raman spectroscopy. The electrocatalytic performance of the prepared catalysts was examined by electrochemical measurements, e.g., cyclic voltammetry, chronoamperometry and CO stripping voltammetry. Among the catalysts, the obtained 1Pt1Pd − CeO2/CNT electrocatalyst provides a high electrochemical surface area, as well as high oxidation activity and durability for the oxidation of methanol, ethanol, and formic acid. The enhancement of the catalytic activity is attributed to changes in the surface electronic structures of Pt, Pd, and CeO2 on the CNT surface that incrementally effect the active sites for oxidation. A required catalytic performance for these oxidations were observed with small-size and high-dispersion of the metal i.e.1Pt1Pd (3.34 nm) on the CeO2/CNT support nanocomposite. The results also show substantial improvement in the kinetics for oxidations and mass transfer efficiency owing to the catalyst structure. Therefore, the prepared catalysts have promising potential for application in low-temperature fuel cells.