Sulfur‐Doped Carbon‐Wrapped Heterogeneous Fe₃O₄/Fe₇S₈/C Nanoplates as Stable Anode for Lithium‐Ion Batteries

Abstract

High‐capacity electrode materials have attracted tremendous attention in energy storage systems. However, the large volume expansion always causes breakdown of electrode materials and capacity fading. In this work, we report the preparation of heterogeneous Fe3O4/Fe7S8/C nanoplates with a high lithium diffusion coefficient and excellent lithium storage performance. The heterogeneous nanoplates can be derived from Fe‐MOF octahedra during the sulfidation process. As an anode for lithium‐ion batteries, the Fe3O4/Fe7S8/C composite exhibits higher specific capacity and better rate capability than Fe3O4/C and Fe7S8/C counterparts. The Fe3O4/Fe7S8/C nanoplates deliver a reversible capacity of 859 mA h g−1 after 100 cycles at 0.1 A g−1. Even at 2 A g−1, a capacity of 549 mA h g−1 can still be remained. The good performances are attributed to the small nanocrystallites, high surface area, and the heterogeneous phase boundaries. The strategy can be potentially applied to other metal oxide/metal sulfide composite phases or even bimetallic sulfides and bimetal oxides for high performance lithium‐ion batteries.

Embedding Heterostructured α‐MnS/MnO Nanoparticles in S‐Doped Carbonaceous Porous Framework as High‐Performance Anode for Lithium‐Ion Batteries

“…Both EIS profiles recorded in Figure S10 display a semicircle in the high frequency followed by a single line in the low frequency region. Note that the semicircle recorded for α‐MnS/MnO is much larger than that for α‐MnS/MnO/SCPF, indicating a lower impedance of the latter and further confirming the substantially enhanced Li‐ion and electron transport within the as‐fabricated composite material (i. e., α‐MnS/MnO/SCPF) [13,16] …”

“…Herein, we report the facile sulfidation process to fabricate micro‐rod composites consisting of heterostructured α‐MnS/MnO NPs and an S‐doped carbon‐based porous framework (denoted as α‐MnS/MnO/SCPF), starting from a Mn‐based metal‐organic framework (Mn–MOF) as the only precursor. Despite some progress in MOF‐derived, heterostructured metal composites, the synthesis of such Mn‐based composites by using MOF‐driven approach is, to the best of our knowledge, reported here for the first time [16] . Herein, we systematically studied the physicochemical features and the Li‐ion storage performance of the as‐obtained composite.…”

Recent Advances in Heterostructured Anode Materials with Multiple Anions for Advanced Alkali‐Ion Batteries

“…[89] Reproduced with permission. [125] 5b,c). It has been reported that multi-anion electrodes experience multi-step electrochemical reactions and some additional reactions, which results in the enhancement of reversible capacities.…”

“…Pan's group experimentally obtained the GITT curves of Fe 3 O 4 /Fe 7 S 8 /C electrodes with heterointerfaces, Fe 3 O 4 /C, and Fe 7 S 8 /C electrodes to verify the effect of the heterostructure. [ 125 ] The GITT curves of the three electrodes were used to calculate the Li + ion diffusion coefficients using the above equation, and the log D values versus lithiation/delithiation states are shown in Figure 5 a. [ 125 ] Fe 3 O 4 /Fe 7 S 8 /C composite electrode materials exhibited higher D values during the charge and discharge processes compared to electrodes with single anions.…”

“…Figure 5. a) GITT curves and Li + ion diffusion coefficients for the 1st and the 2nd cycles. Reproduced with permission [125]. Copyright 2020, Wiley-VCH.…”