Electrooxidation of single-carbon molecules by nanostructured Pd-decorated spongy ceria

Solution combustion synthesis is proposed to fabricate spongy ceria by using two different fuels for combustion: glycine and urea. As-prepared samples are labeled as SCO(Gl)and SCO(Ur)The acid-base properties of the cavities and surfaces of specimens are determined by measuring the pH of zero charges. Both SCO(Gl)and SCO(Ur)powders are decorated by the nanostructured Pd (NSPd) by the wetness incorporation. The NSPd-SCO(Gl)and NSPd-SCO(Ur)represent the high mass current density than NSPd as non-supported palladium for the electrooxidation of single-carbon molecules: methanol, formaldehyde and formic acid. The results show that the NSPd-SCO(Gl)and NSPd-SCO(Ur)are exceptional heterogeneous catalysts. The SCO as the support with porous structural network has been affected considerably on the electrochemical surface area, dispersion, and durability of NSPd. On the other hand, it can be effective for removing the poisoning species of the electrooxidation of single-carbon molecules on NSPd through the lattice oxygen, and the activation of an oxidation-reduction cycle between the high and low chemical valences of cerium, leading to improve the electrocatalytic efficiency of NSPd. Finally, it is confirmed the conversion of methanol to formaldehyde, and then to formic acid during electrooxidation by using cyclic voltammetry studies.