Intermetallic Nanoarchitectures for Efficient Electrocatalysis

Abstract

Intermetallic structures whose regular atomic arrays of constituent elements present unique catalytic properties have attracted considerable attention as efficient electrocatalysts for energy conversion reactions. Further performance enhancement in intermetallic catalysts hinges on constructing catalytic surfaces possessing high activity, durability, and selectivity. In this Perspective, we introduce recent endeavors to boost the performance of intermetallic catalysts by generating nanoarchitectures, which have well-defined size, shape, and dimension. We discuss the beneficial effects of nanoarchitectures compared with simple nanoparticles in catalysis. We highlight that the nanoarchitectures have high intrinsic activity owing to their inherent structural factors, including controlled facets, surface defects, strained surfaces, nanoscale confinement effects, and a high density of active sites. We next present notable examples of intermetallic nanoarchitectures, namely, facet-controlled intermetallic nanocrystals and multidimensional nanomaterials. Finally, we suggest the future research directions of intermetallic nanoarchitectures.

Intermetallic Nanocrystals for Fuel-Cells-Based Electrocatalysis

“…However, the construction of 1D intermetallic nanostructure is not a trivial job. This is because the exertion of external driving force will coarsen nanowires to reduce the high surface energy . For instance, the thermal instability of nanowires makes it impossible to directly transform fcc -phase Pt-based alloy nanowires into fct phase at high temperature, which is because that nanowires will be broken into nanoparticles or shorter nanowires, even be aggregated to form larger agglomerates .…”

Design Strategies of Active and Stable Oxygen Evolution Catalysts for Proton Exchange Membrane Water Electrolysis

“…Various types of nanostructures with different dimensionality have been used to improve electrocatalytic properties. 87,88 One-dimensional (1D) and two-dimensional (2D) nanostructures, including nanoneedles, 89 nanowires, 90−93 and nanosheets, 23,60,94−97 have demonstrated promising activity for the acidic OER. As a notable 3.3.…”

“…Various types of nanostructures with different dimensionality have been used to improve electrocatalytic properties. , One-dimensional (1D) and two-dimensional (2D) nanostructures, including nanoneedles, nanowires, − and nanosheets, ,,− have demonstrated promising activity for the acidic OER. As a notable example of 1D nanostructured catalysts, Lim et al prepared IrO 2 nanoneedles, which exhibited significantly enhanced OER activity compared to that of conventional IrO 2 nanoparticles (Figure a–c) .…”

Design principles for the synthesis of platinum–cobalt intermetallic nanoparticles for electrocatalytic applications

“…The incorporation of early transition metals (i.e., Fe, 14,15 Co, 16,17 and Ni, 18,19 ) and the nano-engineering of Pt-based electrocatalysts are the key technological solutions. 16,[19][20][21][22][23] Platinum-based bimetallic nanoparticles (NPs) often exhibit higher ORR activity than pure Pt electrocatalysts, partly because of the strain and ligand effects. 24,25 Alloying with a 3d transition metal shifts the d-band of Pt downward, 26 decreases the adsorption energy of oxygen species on the surfaces, 27 lowers the activation energy barrier, and, as a consequence, enhances the ORR performance.…”

“…Recent examples on how to control composition, size, and shape and their applications in electrocatalysis will then be presented. It should be noted that there are reviews on Pt-based alloy and intermetallic nanoparticles published previously, 8,20,[41][42][43][44][45][46][47][48][49][50][51][52] and this feature article is focused on Pt-Co intermetallic NPs. Papers on Pt-Co alloys are largely not included in this feature article.…”