A Freestanding Multifunctional Interlayer Based on Fe/Zn Single Atoms Implanted on a Carbon Nanofiber Membrane for High-Performance Li-S Batteries

• Published in: Batteries (Basel) Vol. 10; no. 1; p. 15
• Main Authors: Zhang, Mengdi, Kong, Shuoshuo, Chen, Bei, Wu, Mingbo
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2024
• Subjects: Adsorption; Carbon fibers; carbon nanofibers; Catalysis; Chemical reaction, Rate of; Composition; Current density; Design and construction; Efficiency; Electrolytes; Electrons; freestanding interlayer; Interlayers; Iron; Iron compounds; Lithium; Lithium cells; Lithium sulfur batteries; Materials; Membranes; metal single atoms; Nanofibers; Polysulfides; Reaction kinetics; shuttle effect; Spectrum analysis; Structural stability; Sulfur; Work stations; Zinc; China; Japan
• ISSN: 2313-0105; 2313-0105
• DOI: 10.3390/batteries10010015

By virtue of the high theoretical energy density and low cost, Lithium–sulfur (Li-S) batteries have drawn widespread attention. However, their electrochemical performances are seriously plagued by the shuttling of intermediate polysulfides and the slow reaction kinetics during practical implementation. Herein, we designed a freestanding flexible membrane composed of nitrogen-doped porous carbon nanofibers anchoring iron and zinc single atoms (FeZn-PCNF), to serve as the polysulfide barrier and the reaction promotor. The flexible porous networks formed by the interwoven carbon nanofibers not only offer fast channels for the transport of electrons/ions, but also guarantee the structural stability of the all-in-one multifunctional interlayer during cycling. Highly dispersed Fe and Zn atoms in the carbon scaffold synergistically immobilize sulfur species and expedite their reversible conversion. Therefore, employing FeZn-PCNF as the freestanding interlayer between the cathode and separator, the Li-S battery delivers a superior initial reversible discharge capacity of 1140 mA h g−1 at a current density of 0.5 C and retains a high capacity of 618 mA h g−1 after 600 cycles at a high current density of 1 C.