Tailoring the Void Size of Iron Oxide@Carbon Yolk–Shell Structure for Optimized Lithium Storage

Abstract

High‐capacity lithium‐ion battery anode materials, such as transition metal oxides, Sn and Si, suffer from large volume expansion during lithiation, which causes capacity decay. Introducing sufficient void space to accommodate the volume change is essential to achieve prolonged cycling stability. However, excessive void space may significantly compromise the volumetric energy density. Herein, a method to control the void size in iron oxide@carbon (FeOx@C) yolk–shell structures is developed and the relationship between the void space and electrochemical performance is demonstrated. With an optimized void size, the FeOx@C yolk–shell structure exhibits the best cycling performance. A high reversible capacity of ≈810 mA h g−1 is obtained at 0.2 C, maintaining 790 mA h g−1 after 100 cycles. This contrasts with FeOx@C materials having either smaller or larger void sizes, in which significant capacity fading is observed during cycling. This contribution provides an effective approach to alleviate the volume expansion problem, which can be generally applied to other anode materials to improve their performance in LIBs.

Graphene-like carbon sheet/Fe3O4 nanocomposites derived from soda papermaking black liquor for high performance lithium ion batteries

“…Most notably, the GCS/FO-NC-D electrode also has excellent cycle stability and good Coulombic efficiency even at a high current density of 1000 mA g -1 (Fig 7a). Its initial discharge sepcific capacity is up to 1385.2 mAh g -1 , which is almost 4 times the capacity of a commercial graphite anode (372 mAh/g), and is the highest rate capability compared with those reported in the literature [27][28][29][30][31][50][51][52][53]. And it still exhibits a high reversible capacity (750 mAh g -1 ) after 1400 discharge/charge cycles.…”

Tailoring Iron Oxide Nanostructures for High-Capacity Lithium Storage

“…Figure 10 TEM image of Fe3O4@C yolk@shell spheres (a); [162] TEM image of Fe3O4@C yolk-shell microboxes (b); [165] TEM image of yolk@shell structures with Fe3O4@Fe3C yolks and carbon nanospindle shells (c); [164] TEM image (d) and cycling performance (e) of FeOx@C yolk-shell structures with an optimized void size. [163] Fe3O4-based hierarchical structures also demonstrate high lithium storage performances. Long, Ling, and co-workers reported the preparation of Fe3O4-C micro-flowers constructed by nanoflakes (Figures 11a and 11b).…”

“…To study the effects of void size on the electrochemical performances, Yu, Zhou, and co-workers prepared a series of FeOx@C yolk@shell structures (Fe3O4 as the dominant phase) with tailored void space ( Figure 10d). [163] Only with an optimized void size, the FeOx@C yolk@shell structures demonstrated the best cycling performance (Figure 10e). Figure 10 TEM image of Fe3O4@C yolk@shell spheres (a); [162] TEM image of Fe3O4@C yolk-shell microboxes (b); [165] TEM image of yolk@shell structures with Fe3O4@Fe3C yolks and carbon nanospindle shells (c); [164] TEM image (d) and cycling performance (e) of FeOx@C yolk-shell structures with an optimized void size.…”

“…[160] With desirable free spaces for volume change accommodation, yolk@shell structures have also been fabricated to boost the electrochemical performances of Fe3O4. [162][163][164][165][166] Guan et al constructed…”

A facile solution combustion synthesis of nanosized amorphous iron oxide incorporated in a carbon matrix for use as a high-performance lithium ion battery anode material

“…18,20 Many reports have been engaged with the production and application of iron oxide-carbon nano-composites for the anode of LIBs. [29][30][31][32] TG analysis (Fig. 3-(1)) was used to determine the reaction behavior of the various samples.…”