Intermetallic <scp>PdCd</scp> Core Promoting <scp>CO</scp> Tolerance of Pd Shell for Electrocatalytic Formic Acid Oxidation<sup>†</sup>
Ming‐Xi Chen, Yue Liu, Tian‐Wei Song, Ruilin Wei, Xiaodong Zhuang, Yao‐Yue Yang, Hai‐Wei Liang
Abstract
Comprehensive Summary Liquid fed fuel cells such as direct formic acid fuel cells (DFAFCs) are considered to be promising power sources for portable electronic devices. However, the poison of CO intermediates on the state‐of‐the‐art platinum and palladium‐based electrocatalysts for the formic acid oxidation reaction (FAOR) at the anode hampers the implementation of DFAFCs technologies. Here, we report a core/shell catalyst consisting of intermetallic PdCd core and Pd shell (i‐PdCd@Pd) with promoted CO anti‐poison ability and thus FAOR performance. The optimal i‐PdCd@Pd catalyst exhibits a high mass activity and specific activity at peak potential, which are 24 and 4 times greater than that of commercial Pd/C catalyst, respectively. We understand by in‐situ surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRA) and X‐ray photoelectron spectroscopy (XPS) that in i‐PdCd@Pd, the intermetallic PdCd under‐layers can induce the downshift of d‐band center of surface Pd atoms, which would improve the CO tolerance and thus promote the FAOR performance.