Accelerated Multi-step Sulfur Redox Reactions in Lithium-Sulfur Batteries Enabled by Dual Defects in Metal-Organic Framework-based Catalysts.
Angew Chem Int Ed Engl
; 62(42): e202306901, 2023 Oct 16.
Article
em En
| MEDLINE
| ID: mdl-37302981
The sluggish sulfur redox kinetics and shuttle effect of lithium polysulfides (LiPSs) are recognized as the main obstacles to the practical applications of the lithium-sulfur (Li-S) batteries. Accelerated conversion by catalysis can mitigate these issues, leading to enhanced Li-S performance. However, a catalyst with single active site cannot simultaneously accelerate multiple LiPSs conversion. Herein, we developed a novel dual-defect (missing linker and missing cluster defects) metal-organic framework (MOF) as a new type of catalyst to achieve synergistic catalysis for the multi-step conversion reaction of LiPSs. Electrochemical tests and first-principle density functional theory (DFT) calculations revealed that different defects can realize targeted acceleration of stepwise reaction kinetics for LiPSs. Specifically, the missing linker defects can selectively accelerate the conversion of S8 âLi2 S4 , while the missing cluster defects can catalyze the reaction of Li2 S4 âLi2 S, so as to effectively inhibit the shuttle effect. Hence, the Li-S battery with an electrolyte to sulfur (E/S) ratio of 8.9â
mL g-1 delivers a capacity of 1087â
mAh g-1 at 0.2â
C after 100â
cycles. Even at high sulfur loading of 12.9â
mg cm-2 and E/S=3.9â
mL g-1 , an areal capacity of 10.4â
mAh cm-2 for 45â
cycles can still be obtained.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
China
País de publicação:
Alemanha