Remote Synergy between Heterogeneous Single Atoms and Clusters for Enhanced Oxygen Evolution

Abstract

Integrating single atoms and clusters into one system is a novel strategy to achieve desired catalytic performances. Compared with homogeneous single-atom cluster catalysts, heterogeneous ones combine the merits of different species and therefore show greater potential. However, it is still challenging to construct single-atom cluster systems of heterogeneous species, and the underlying mechanism for activity improvement remains unclear. In this work, we developed a heterogeneous single-atom cluster catalyst (Co n Ir 1 /N−C) for efficient oxygen evolution. The Ir single atoms worked in synergy with the Co clusters at a distance of about 8 Å, which optimized the configuration of the key intermediates. Consequently, the oxygen evolution activity was significantly improved on Co n Ir 1 /N−C relative to the Co cluster catalyst (Co n /N−C), exhibiting an overpotential lower by 107 mV than that of Co n /N−C at 10 mA cm −2 and a turnover frequency 50.9 times as much as that of Co n /N−C at an overpotential of 300 mV.

Mechanism of Particle-Mediated Inhibition of Demetalation for Single-Atom Catalytic Sites in Acidic Electrochemical Environments

“…At a particle size of 0.7 nm (equivalent to 19 Pt atoms), the farthest interaction distance observed was 0.8 nm, while at a larger particle size of 0.9 nm (27 Pt atoms), the distance increased to 1.5 nm (Figure S9). This long-range interaction has been proposed by several research groups. − …”

Single-atom sites combined with metal nano-aggregates for efficient electrocatalysis

“…11d). 100 The OER overpotential for Co n Ir 1 /N−C at 10 mA cm −2 was only 262 mV, and there was no significant degradation of OER activity during 25 h. The calculated MA and TOF (turnover frequency) of Co n Ir 1 /N−C both exceeded Co n /N−C approximately 50 times under the overpotential of 300 mV (Fig. 11e).…”

Review of Emerging Atomically Precise Composite Site‐Based Electrocatalysts

“…[ 96 ] Copyright 2023, American Chemical Society. [ 71 ] Copyright 2023, American Chemical Society. [ 97 ] Copyright 2023, American Chemical Society.…”

“…Ding et al proposed a remote synergistic effect between different metal species toward the OER in a heterogeneous single atom‐atomic cluster composite site‐based catalysts. [ 71 ] The Ir SA sites cooperated with Co AC sites at a distance of ≈8 Å, optimizing the configuration of critical intermediates. Moreover, hydrogen bonding formed between the adsorbed oxygenated groups, which enhanced the adsorption of *OOH.…”