Interface-confined precise processing of Ag nanowire into AgPd-nanoparticle-sealed AgAu nanotroughs for boosting ethanol electrooxidation

Abstract

The functions of nanomaterials are closely linked with their fine structures and compositions. Precisely processing nanoparticles into morphology- and composition-varied nanostructures can a cutting-edge technology for producing complex nanostructures. Herein, we develop an interface-confined precise processing strategy towards toluene/water-interfacial Ag nanowires. Interfacial Ag nanowires are transformed into AgPd-nanoparticle-sealed AgAu nanotroughs with abundant AgPd/AgAu hetero-junctions (i.e., AgPdAu hetero-junction nanostructures). By adjusting the reaction conditions, composition-varied AgPdAu hetero-junction nanostructures can be obtained. The formation of AgPdAu hetero-junction nanostructures can be attributed to interface-confined precise etching towards Ag nanowires separately from the two subphases of the water and the toluene. Composition-optimized Ag13Pd67Au20 hetero-junction nanostructure shows satisfactory catalytic performance towards ethanol electrooxidation: ∼4 and 2 times in electrochemical-activity-surface-area-normalized activities; ∼6 and 5 times in mass-normalized activities higher than commercial Pd/C and Pt/C, respectively. The outstanding catalytic capability of Ag13Pd67Au20 may be attributed to optimized composition, porous nanostructures as well as abundant AgPd/AgAu hetero-junctions. This work demonstrates the feasibility of precisely processing interfacial nanoparticles, opening the way for creating morphology-well-defined composition-varied complex nanostructures.