Fe₃SnC@CNF: A 3 D Antiperovskite Intermetallic Carbide System as a New Robust High‐Capacity Lithium‐Ion Battery Anode

Abstract

A 3 D intermetallic anti‐perovskite carbide, Fe3SnC, is reported as a Li‐ion battery anode. Single‐phase Fe3SnC showed a reversible Li‐ion capacity of 426 mAh g−1 that increased significantly (600 mAh g−1) upon its in situ synthesis by electrospinning and pyrolysis to render a conducting carbon nanofibre (CNF) based composite. Importantly, the Fe3SnC@CNF composite showed excellent stability in up to 1000 cycles with a remarkable 96 % retention of capacity. The rate performance was equally impressive with a high capacity of 500 mAh g−1 delivered at a high current density of 2 A g−1. An estimation of Li ion diffusion from the electrochemical impedance data showed a major enhancement of the rate by a factor of 2 in the case of Fe3SnC@CNF compared to the single‐phase Fe3SnC sample. Post‐cyclic characterisation revealed that the unit cell was retained despite a volume expansion upon the inclusion of four Li atoms per unit cell, as calculated from the capacity value. The cyclic voltammogram shows four distinctive peaks that could be identified as the sequential incorporation of up to four Li atoms. First‐principles DFT calculations were performed to elucidate the favourable sites for the inclusion of 1–4 Li atoms inside the Fe3SnC unit cell along with the associated strain.

Ultrafine Mix-Phase SnO-SnO2 Nanoparticles Anchored on Reduced Graphene Oxide Boost Reversible Li-Ion Storage Capacity beyond Theoretical Limit

“…Insertion-type anodes such as layered transition-metal dichalcogenides (TMDs) and two-dimensional (2D) layered carbides such as MXenes have some specific limitations in energy density, and these do undergo unstable electrochemical kinetics with fast charging issues. − Owing to the very high-volume change under an electrochemical cycling condition and thereby eventual cell failure, alloying systems are also out of consideration for use on their own . On the other hand, conversion systems, although challenged with several drawbacks like high voltage polarization and thereby low energy efficiency, are still being researched extensively due to high specific capacity, reasonably good rate performance, and fair cyclic stability. , …”

“…14 On the other hand, conversion systems, although challenged with several drawbacks like high voltage polarization and thereby low energy efficiency, are still being researched extensively due to high specific capacity, reasonably good rate performance, and fair cyclic stability. 15,16 Tin oxides (like SnO 2 and SnO)-based nanostructured materials have absolutely marked their presence in the Li-ion battery community as high-capacity negative electrodes. 17 These systems have a distinctive combination of an alloying and conversion reaction mechanism involved in the lithiation and delithiation process; lithium can be repeatedly released and stored and, thus, can offer a very high theoretical (1494 mA h g −1 ) capacity.…”

Interfacial Electron Delocalization in Engineering Nanosized Anti-Perovskite Nitride for Efficient CO2 Electroreduction

“…With a well-defined crystal structure and highly flexible composition, theoretically, such anti-perovskite materials are suitable for investigation of structure–activity relationship in chemistry; nevertheless, the synthesis of nanosized anti-perovskites or their application in chemistry has been much less reported. Among various anti-perovskites, transition metal nitrides have been explored in solid-state chemistry. ,, For instance, Cu 3 NPd nanocrystals were explored as electrocatalysts for oxygen reduction reaction; CuNCo 3– x V x and the Cu 1– x NNi 3– y /FeNiCu composites demonstrated excellent performance for oxygen evolution reaction. , Methods such as chemical vapor deposition, chemical solution deposition, spark-plasma sintering, and so forth − were developed to prepare these transition metal nitrides using N 2 or NH 3 as the most common nitrogen source. Nevertheless, synthesis of such transition metal nitrides usually requires high temperature; as a result, most of the existing anti-perovskite nitrides occur in the micrometer regime, which limits their application in heterogeneous catalysis.…”

Search for New Anode Materials for High Performance Li-Ion Batteries

“…In our work on carbide systems, we focused on a relatively less explored area of 3D carbides. Thus, Roy et al studied a unique 3D carbide intermetallic with antiperovskite geometry, namely Fe 3 SnC, for Li battery anode . This antiperovskite was specifically chosen because of its high mechanical robustness (bulk; B to sheer; G modulus ratio 2.5, high ductility; B/G > 1.75) and the presence of two redox active centers (Fe, Sn), which can allow the facile accommodation of Li-ions in the tetrahedral/octahedral sites in the 3D lattice of carbide despite the volume expansion.…”

“…(a) PXRD pattern of the as-synthesized single-phase Fe 3 SnC particles. Reprinted in part with permission from ref . Copyright 2020, John Wiley and Sons.…”