Single-Atom Catalysts: From Design to Application

Abstract

Single-atom catalysis is a powerful and attractive technique with exceptional performance, drastic cost reduction and notable catalytic activity and selectivity. In single-atom catalysis, supported single-atom catalysts contain isolated individual atoms dispersed on, and/or coordinated with, surface atoms of appropriate supports, which not only maximize the atomic efficiency of metals, but also provide an alternative strategy to tune the activity and selectivity of catalytic reactions. This review will highlight the attributes of single-atom catalysis and summarize the most recent advancements in single-atom catalysts with a focus on the design of highly active and stable single atoms. In addition, new research directions and future trends will also be discussed.

Heterogeneous Single Atom Electrocatalysis, Where “Singles” Are “Married”

“…Second, advanced structural characterization techniques are desperately needed to fully understand the local bonding and coordination of each and every single atom. Currently, atomic resolution TEM/STEM, XAS, and Fourier transform infrared spectroscopy are the most frequently employed techniques for structural analyses of SACs . Both the morphology and overall coordination environment of some single atom sites can be identified.…”

“…Currently, atomic resolution TEM/STEM, XAS, and Fourier transform infrared spectroscopy are the most frequently employed techniques for structural analyses of SACs. [125,126] Both the morphology and overall coordination environment of some single atom sites can be identified. However, it is still of considerable challenge to investigate the distribution of local coordination and the how they are to respond to the environmental conditions by these known techniques.…”

Establishing reactivity descriptors for platinum group metal (PGM)-free Fe–N–C catalysts for PEM fuel cells

“…[4][5][6][12][13][14][15][16][17][18][19][20][21][22] The most prominent example of PGM-free ORR electrocatalysts for acidic medium is the family of iron-(or cobalt-) and nitrogen-doped high surface area carbon matrix, typically referred as ''Fe-N-C'' catalysts, with atomically-dispersed Fe cations coordinated with nitrogen atoms as the recognized most active sites. 5,[23][24][25][26][27][28][29][30][31][32] Unlike PGM-based single atom catalysts, where the atoms exist in a carbon matrix as a sole atoms 33,34 or dimeric compounds, 35 iron generally has to be coordinated with hetero atoms. Several general approaches have been established in order to control the carbon micro and/or meso-porosity in M-N-C catalysts, a key for high performance: functionalisation of microporous carbon blacks with metal and N precursors, 4 hard-templating of C and N precursors with e.g.…”

On the Real Nature of Rh Single‐Atom Catalysts Dispersed on the ZrO2 Surface

“…Despite the apparent success of SAC in promoting various catalytic reactions, [12,13,14] some problems remain. For instance, isolated metal atoms on a support tend to diffuse and aggregate forming larger clusters during the synthetic process or in the course of the catalytic reactions due to the low diffusion barriers.…”