Reduced graphene oxide (RGO)-supported Pd–CeO2 nanocomposites as highly active electrocatalysts for facile formic acid oxidation†
Abstract
Stable and efficient electrocatalysts capable of oxidizing a formic acid molecule are highly required to realize direct formic acid fuel cells (DFAFCs) as promising energy conversion sources. Herein, the electrocatalytic activity of Pd–CeO2 nanocomposites with an average particle size of 5.32 nm dispersed on a reduced graphene oxide (RGO) support, i.e. Pd–CeO2/RGO, towards the formic acid oxidation reaction (FAOR) was studied. The microstructural and morphological details of the as prepared electrocatalysts were studied by X-ray diffraction, electron microscopy and cyclic voltammetry (CV) techniques. The electrocatalytic activity of the nanoparticles for the FAOR was recorded in a mixed solution of N2-saturated 0.5 M sulfuric acid and 0.5 M formic acid at room temperature (RT). The Pd–CeO2/RGO catalyst possesses superior FAOR activity and more stability compared with the prepared Pd/RGO and commercial Pd/C catalysts. The facile fabrication route presented here is capable of being extended to synthesize multifunctional nanocomposites for electrocatalytic applications.