A robust electrocatalytic activity and stability of Pd electrocatalyst derived from carbon coating.

Palladium (Pd) as an efficient anodic catalyst has been extensively investigated in direct formic acid fuel cells (DFAFCs); while, Pd catalyst is electrochemically unstable in acidic electrolyte resulting in low stability retarding the widespread application of DFAFCs. In this study, a new method is invented to prevent the Pd nanoparticles from rapid dissolution by carbon layer originated from the carbonization of glucose. Ascribing to the presence of carbon layer, Pd electrocatalyst demonstrates much higher stability in comparison with Pd electrocatalyst without carbon layer in the course of stability tests. Robust electrocatalytic activities toward formic acid and methanol/ethanol oxidation are observed for carbon-stabilized Pd electrocatalyst resulted from the higher content of metallic Pd atoms coming from the carbonization process, in which Pd (II) species are further reduced. Moreover, the fuel cell performance of carbon-stabilized Pd electrocatalyst reaches 90 mW cm Pd −2 measured with 1 M formic acid; while, power density of bare Pd electrocatalyst is only 74 mW cm Pd −2. This work highlights that carbon layer carbonized from glucose improves not only the stability of Pd electrocatalyst, but also the electrocatalytic activity. • Protective carbon layer is coated on Pd nanoparticles via carbonization of glucose. • High stability and catalytic activity are obtained after coating with carbon layer. • Carbon layer coated Pd catalyst exhibits a higher fuel cell output of 90 mW cm−2. [ABSTRACT FROM AUTHOR]