Pronounced effect of yttrium oxide on the activity of Pd/rGO electrocatalyst for formic acid oxidation reaction.

A highly efficient and stable electrocatalyst comprised of yttrium oxide (YO) and palladium nanoparticles has been synthesized a sodium borohydride reduction approach. The molar ratio of Pd and Y was varied to fabricate various electrocatalysts and the oxidation reaction of formic acid was checked. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD) are used to characterize the synthesized catalysts. Among the synthesized catalysts (PdY/rGO), the optimized catalyst , PdY/rGO exhibits the highest current density (106 mA cm) and lowest onset potential compared to Pd/rGO (28.1 mA cm) and benchmark Pd/C (21.7 mA cm). The addition of YO to the rGO surface results in electrochemically active sites due to the improved geometric structure and bifunctional components. The electrochemically active surface area 119.4 m g is calculated for PdY/rGO, which is ∼1.108, ∼1.24, ∼1.47 and 1.55 times larger than PdY/rGO, PdY/rGO, Pd/C and Pd/rGO, respectively. The redesigned Pd structures on YO-promoted rGO give exceptional stability and enhanced resistance to CO poisoning. The outstanding electrocatalytic performance of the PdY/rGO electrocatalyst is ascribed to uniform dispersion of small size palladium nanoparticles which is possibly due to the presence of yttrium oxide.