Morphology‐ and composition‐controlled silver‐containing rhodium nanoparticles for the oxygen reduction reaction

Abstract

Rh nanoparticles (RhNPs) have attracted significant attention due to their superior electrocatalytic activity in several energy conversion reactions. However, studies relating their morphology and performance are rare. In this study, three types of RhNPs, i.e., nanoshells, nanoframes, and porous nanoplates, were synthesized via inverse‐directional galvanic replacement. The relationship between the performance of the RhNPs at catalyzing the oxygen reduction reaction (ORR) and their morphology was investigated using cyclic voltammetry, linear sweep voltammetry, the Tafel slope, and electrochemical impedance spectroscopy. X‐ray photoelectron spectroscopy and X‐ray diffraction data revealed that the RhNPs contained different Rh/Ag ratios. All the RhNPs exhibited long‐term stability under acidic conditions. In particular, nanoshell‐structured RhNPs exhibited superior ORR activity as determined from the slope of the Tafel plot, the number of electrons, and the onset potential compared to a commercial Rh electrocatalyst and other RhNPs. Evidently, controlling the morphology and composition of RhNPs greatly facilitates efficient electrocatalysis.

Study of Oxygen Reduction Reaction on Polycrystalline Rhodium in Acidic and Alkaline Media

“…The same or similar ORR kinetics apply to electrocatalysts based on supported rhodium nanoparticles (Rh NPs), which have attracted significant attention due to their excellent electrocatalytic performance. Kinetic studies of the oxygen reduction reaction involved different supported rhodium catalysts in various solutions [22][23][24].…”

Investigation of electrocatalytic activity of palladium nanoparticle for ammonia borane oxidation via single‐entity electrochemistry

“…10,15 Nanoparticles (NPs) have found widespread application as catalysts in the field of energy due to their exceptional catalytic prowess, which stems from their substantial surface-to-volume ratio. [16][17][18] The electrocatalytic performance of NPs is influenced by factors such as size, shape, capping agent, and surface lattice structure. [19][20][21] However, traditional electroanalytical techniques used to investigate NPs have limitations when it comes to discerning the properties of individual NPs, as they rely on the ensemble behavior of NPs rather than examining single NPs individually.…”

“…Nanoparticles (NPs) have found widespread application as catalysts in the field of energy due to their exceptional catalytic prowess, which stems from their substantial surface‐to‐volume ratio 16–18 . The electrocatalytic performance of NPs is influenced by factors such as size, shape, capping agent, and surface lattice structure 19–21 .…”

One pot production of Co core/carbon shell materials and their electrocatalytic properties

“…2 The oxygen reduction reaction (ORR) is a slow process due to its requirement of transferring four electrons. 3,4 While Pt/C demonstrates exceptional electrocatalytic ORR performance, its high cost and low oxidation stability present significant challenges. 5 In this regard, there has been significant research into alternatives such as Pt-based alloys with reduced Pt content, carbon-based materials without metal components, single-atom-based catalysts, and non-Pt materials incorporating cost-effective metal elements.…”

“…These systems rely on efficient electrocatalysts to facilitate the reduction of oxygen molecules to water at a cathode 2 . The oxygen reduction reaction (ORR) is a slow process due to its requirement of transferring four electrons 3,4 . While Pt/C demonstrates exceptional electrocatalytic ORR performance, its high cost and low oxidation stability present significant challenges 5 .…”