Sacrificial Template Method to Synthesize Atomically Dispersed Mn Atoms on S, N-Codoped Carbon as a Separator Modifier for Advanced Li-S Batteries.
ACS APPLIED MATERIALS & INTERFACES 2022;
14:42123-42133. [PMID:
36075102 DOI:
10.1021/acsami.2c12114]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Efficient and durable electrocatalysts are important for polysulfide conversion in high-performance Li-S batteries. Herein, we report a sacrificial template strategy to synthesize a sulfur/nitrogen-codoped carbon-supported manganese (Mn) single-atom catalyst (Mn/SNC). The synthesis is enabled by fabricating a novel precursor, i.e., cadmium sulfide (CdS) wrapped with Mn ion-impregnated polyporrole (CdS@Mn-PPy), and subsequent pyrolysis. During pyrolysis, the CdS template is decomposed into Cd and S, PPy-derived carbon is doped with N and S, and Mn ions are reduced to Mn atoms, forming Mn-N active sites. The evaporation of Cd atoms/clusters creates abundant pores in the carbon substrate to expose the active sites and facilitate ion transport, and S atoms can form edge C-S-C bonds to improve the activity of Mn-N sites. Benefiting from the above advantages, the Mn/SNC catalyst markedly enhances the performance of Li-S batteries, delivering an initial capacity of 1563.7 mAh g-1 at 0.1C, a capacity decay of only 0.037% per cycle after 1600 cycles at 2C; a capacity of 1045.1 mAh g-1 at a high sulfur loading of 7.44 mg cm-2 at 0.2C, and a capacity retention of 73.1% after 180 cycles. This work provides a strategy that may benefit further the rational design and development of single-atom catalysts for application in renewable energy.
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