Boosting Dual‐Directional Polysulfide Electrocatalysis via Bimetallic Alloying for Printable Li–S Batteries. (13th October 2020)

• Record Type: Journal Article
• Authors: Shi, Zixiong; Sun, Zhongti; Cai, Jingsheng; Fan, Zhaodi; Jin, Jia; Wang, Menglei; Sun, Jingyu
• Is Part Of: Advanced functional materials. Volume 31:Number 4(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-13
• Subjects: 3D printing -- CoFe alloys -- dual‐directional electrocatalytic effect -- electrocatalysts -- Li–S batteries; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202006798
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: The rational design of electrocatalyst has readily stimulated a burgeoning interest in expediting polysulfide conversion and hence essentially restricting the "shuttle effect" in Li–S systems. Nevertheless, seldom efforts have been devoted to probing the dual‐directional polysulfide electrocatalysis to date. Herein, a CoFe alloy decorated mesoporous carbon sphere (CoFe‐MCS) serving as a promising mediator for Li–S batteries is reported. Such bimetallic alloying boosts dual‐directional electrocatalytic activity toward effective polysulfide conversion throughout detailed electroanalytic characterization, theoretical calculation, and operando instrumental probing. Accordingly, the S@CoFe‐MCS cathode harvests a stable cycling with a low capacity decay rate of 0.062% per cycle over 500 cycles at 2.0 C. More encouragingly, benefiting from the optimized redox kinetics and delicate grid architecture, printable S@CoFe‐MCS cathode achieves an excellent rate performance at a sulfur loading of 4.0 mg cm −2 and advanced areal capacity of 6.0 mAh cm −2 at 7.7 mg cm −2 . This work explores non‐precious metal alloy electrocatalysts in printable cathodes toward dual‐directional polysulfide conversion, holding great potential in the pursuit of Li–S commercialization. Abstract : A CoFe alloy electrocatalyst supported on mesoporous carbon synthesized via a bimetallic organic framework pyrolysis strategy exhibits robust dual‐directional electrocatalysis toward polysulfide conversion, thus enabling excellent areal capacity and cycling stability for 3D‐printed sulfur cathodes with high sulfur loadings.