| Abstract |
Single-atom catalysts (SACs) based on noble metals play irreplaceable roles in the field of catalysis but unfortunately suffer from spatial constraints ranging from either lattice substitution, atomic dilution, or in-layer immobilization. Herein, this work was designed to overcome the limitation by locating discrete dangling coordinatively unsaturated [IrO5] motif atop γ-phase cobalt oxyhydroxide (γ-CoOOH) nanosheets to create a spatially novel catalyst (Ir1/CoOOHsur). For comparison, the lattice-doped catalyst (Ir1/CoOOHlat) was also synthesized via substituting Co in γ-CoOOH by Ir single atoms. The distinct location arrangements of Ir single atoms generated two different active sites that both weakened the adsorption of oxygenated intermediates relative to γ-CoOOH due to the upshifted O 2p-band center. Moreover, Ir1/CoOOHsur displayed a much weaker adsorption capability (closer to an ideal catalyst) than Ir1/CoOOHlat. Therefore, the spatial and electronic effects of discrete dangling [IrO5] motifs atop Ir1/CoOOHsur synergistically optimized the adsorption of oxygenated intermediates and thus gained the lowest energy barrier of the rate-determining step for oxygen evolution reaction. When used as the cathode catalyst in rechargeable zinc-air batteries, Ir1/CoOOHsur exhibited higher power density (101 mW cm−2) and cycling durability (800 h) than IrO2 (94 mW cm−2, 50 h). This study broadens noble metal-based SACs analogues and offers appealing opportunity to design target catalysts with the synergism of spatial and electronic effects for diverse catalytic applications. |
| Authors |
Bo Yang  , Meiqian Li , Zhirong Zhang , Shaoqing Chen , Miaomiao Wang , Sheng Li , Libo Deng , Rui Si , Maohong Fan  , Huihuang Chen
|
| Journal Info |
Elsevier BV | Applied catalysis. B, Environmental , vol: 340
, pages: 123227 - 123227
|
| Publication Date |
1/1/2024 |
| ISSN |
0926-3373 |
Type |
article |
| Open Access |
bronze
|
| DOI |
https://doi.org/10.1016/j.apcatb.2023.123227 |
| Keywords |
Catalysts (Score: 0.502887) , Electrolyte Design (Score: 0.500049)
|
