Ag/Co3O4 as an effective catalyst for glycerol electro-oxidation in alkaline medium

Abstract

Herein, we report two different modes of combustion synthesis to prepare Ag/Co3O4 for glycerol electro-oxidation reaction. The synthesis technique allows us to deposit and disperse cobalt on the surface of silver and understand the effect of silver-cobalt interactions on the electrocatalytic performance. The bimetallic AgCo catalyst was synthesized via conventional solution combustion (AgCo-SCS); in addition, a novel second wave solution combustion synthesis (AgCo-SWC) was also used to synthesize a sample with a higher degree of surface alloying between the elements. XRD results of AgCo-SWC show peak shifts in 2? to indicate the formation of a solid solution alloy that could improve the structural and electronic characteristic of the material. In AgCo-SCS, smaller Ag particles are found to be more on the surface, while in AgCo-SWC, Ag particles were largely covered with cobalt particles. The electro-oxidation results indicate that AgCo-SWC has improved electrochemical properties in terms of higher oxidation current and lower onset potential, which makes it an ideal candidate for glycerol oxidation reaction.