(Invited) Gold Nanoparticles for Key Reactions in Electrochemical Energy Conversion

Glucose oxidation (GOR) and oxygen reduction (ORR) are two intensively studied reactions for their concern in the development of sustainable energy sources. The oxidation of carbon monoxide (CO), considered as a poisoning reactant in organics conversion, is also a key reaction to be understood in electrocatalysis. Efficient catalysts should be designed for this purpose. Moreover, due to the surface reactions involved, the control of the catalysts' shape, size and structure is required to understand their activity and improve their stability. The outstanding properties exhibited by gold at nanoscale lead to various applications, including electrocatalysis which depends on the nanoparticles (NPs) surface structure and morphology [1]. Gold nanospheres (AuNSs) and pentatwinned gold nanorods (AuPTW NRs) were prepared by a revisited Turkevich synthesis and seed mediated methods respectively. Their surfaces were probed by the lead underpotential deposition (upd Pb ) and the reduction of 4-mercaptobenzoic acid to reveal, respectively, the low and high index facets. The (100) facets of AuNSs are considered to be the active sites for glucose and CO oxidation in alkaline medium, while a AuPTW NRs@Pd core-shell material markedly promotes the ORR activity. Figure 1