Interface-Engineered Fe₃O₄/MXene Heterostructures for Enhanced Lithium-Ion Storage

Abstract

Fe3O4 is a potential anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity (926 mAh g–1) and low cost, but its practical application is restricted by its low electrical conductivity and large volume changes during lithiation/delithiation. Herein, rationally designed Fe3O4/MXene hybrid heterostructures are constructed using an interfacial self-assembly approach that allows spontaneous deposition of Fe3O4 nanodots over Ti3C2T x MXene nanosheets. The van der Waals-facilitated self-assembly process results in an ideal interfacial arrangement where Fe3O4 and MXene are in a complementary configuration. Among the different mass ratio arrangements, the self-assembled composite with 70 wt % Fe3O4 (Fe3O4/MXene-7) exhibits a much enhanced capacity of 782.7 mAh g–1 at 0.1 A g–1 after 100 cycles, which retains 667.9 mAh g–1 at 1 A g–1 after 600 cycles without any capacity decay. The devised anode could further maintain a reversible capacity of 279.1 mAh g–1 when the current density reaches 5 A g–1. Moreover, the charge storage capability of Fe3O4/MXene-7 is concluded to follow a dual-mode charge storage (battery capacitive) mechanism, which anticipates the constructed heterostructures promising future for next-generation LIBs.

Hierarchical MXene/transition metal oxide heterostructures for rechargeable batteries, capacitors, and capacitive deionization

“…5a). 79 When the Fe 3 O 4 nanodots were anchored in the MXene sheets, the (002) peak of the Fe 3 O 4 / MXene heterostructure was significantly shifted to the left in angle compared with the MXene (Fig. 5b), indicating that the MXene interlayer spacing was increased.…”

“…Nevertheless, MXene electrodes suffer from the following issues: (1) low capacity or capacitance; (2) MXene sheets can be easily restacked during the preparation of the electrodes; (3) the electronic conductivity of MXene sheets decreases with the oxidation of the MXene; and (4) termination -F groups may influence the electrolyte infiltration into the electrodes. [57][58][59][60][61][62][63][64][65][66][67][68] To solve the above problems and enhance the electrochemical performance of MXenes, a lot of effort has been made to, for example, construct few-layer MXene sheets, 69 nanostructured MXene, 70,71 porous MXene, [72][73][74][75][76][77] MXene/transition metal oxides (TMOs), [78][79][80][81] and MXene/transition metal chalcogenides (TMCs). [82][83][84][85] In particular, constructing hierarchical MXene/ TMO heterostructures can remarkably improve the electrochemical performance of MXene-based electrodes in batteries, capacitors, and CDI.…”

“…5 (a) Schematic diagram of the preparation of Fe 3 O 4 /MXene heterostructures, (b) XRD pattern of MXene nanosheets, Fe 3 O 4 nanodots, and Fe 3 O 4 /MXene, (c) TEM image of Fe 3 O 4 /MXene, and (d) elemental mapping of Fe, O and Ti in Fe 3 O 4 /MXene. Reproduced with permission 79. Copyright 2021, American Chemical Society.…”

Alkali-Induced Porous MXene/Carbon Nanotube-Based Film Electrodes for Supercapacitors

“…MXenes, a new family of 2D materials, have sparked interest in a variety of disciplines, including energy storage, − catalysis, sensors, electromagnetic interference shielding, and so on, based on their intriguing physicochemical characteristics. MXenes are synthesized by extracting the “A” layer of the M n +1 AX n phase precursors, following the formula of M n +1 X n T x , where M stands for early transition metal elements (e.g., Ti, Zr, V, Nb, Cr, and Mo), X is carbon or/and nitrogen, n = 1–4, and T x is the surface terminations (e.g., −F, −OH, −O, and −Cl).…”

Architecture of ZnFe2O4@V2CTx MXene Hybrid Anodes via In Situ Chemical Co-precipitation for Optimized Lithium-Ion Battery

“…Since the discovery of Ti 3 C 2 MXene in 2011, MXenes opened up a new milestone in two-dimensional (2D) materials . The unique layered structures and high specific surface area give them rapid ion diffusion and extensive tunnels for ion insertion, which correspond to the requirements of energy storage materials. , When ZFO nanoparticles are combined with MXenes, MXenes can essentially lower their volume expansion and strengthen their capacity. For instance, Yu et al obtained ZFO/Ti 3 C 2 T x with a reversible capacity of 436 mAh g –1 after 100 cycles, and the value was higher than that of a Ti 3 C 2 T x nanosheet and pure ZFO nanoparticles .…”