Sonochemical reduction method for synthesis of TiO2[sbnd]Pd nanocomposites and investigation of anode and cathode catalyst for ethanol oxidation and oxygen reduction reaction in alkaline medium

Abstract

The development of the superior Pt-free electrocatalyst for enhancing electrocatalytic activity and stability towards the EOR (ethanol oxidation reaction) and ORR (oxygen reduction reaction) are very important for the commercialization of fuel cells. In this work, the palladium nanoparticles (Pd NPs) deposited on titanium dioxide nanospheres (PdTiO2) were successfully prepared by the sonochemical reduction method. Hence, the TiO2 nanospheres were directly used as the templates for nucleation and growth of Pd NPs over their surface using PdCl4− as the Pd precursor, PVP (Polyvinylpyrrolidone) as the stabilizer, ascorbic acid (AA) as the reducing agent, and water as the solvent. The size of Pd NPs is remarkably controlled using the sequential reduction steps by adding an excess of PdCl4−. The excellent electrocatalytic activity towards EOR and ORR is ascribed by the synergistic effect of the Pd nanoparticles and TiO2 nanospheres support. This unique nanocomposite should be of great benefit to the construction of commercial fuel cell systems.