Vertically Aligned MXene Nanosheet Arrays for High‐Rate Lithium Metal Anodes

Abstract

Lithium (Li) metal is considered as one of the best anode materials due to its high theoretical capacity and low reduction potential. However, its practical application is restricted by uneven Li metal dendrite growth. Herein, vertically aligned Ti3C2Tx MXene nanosheet arrays synthesized by a facile ice template assisted blade coating method are adopted to regulate Li metal nucleation and guide Li metal deposition. This kind of vertical structure exhibits low tortuosity that can achieve homogeneous and fast Li transport. In addition, the rich F and O groups on the Ti3C2Tx surface are conducive to the formation of a uniform solid–electrolyte interphase layer, which plays an important role in regulating the nucleation and growth of Li metal. Consequently, the vertically aligned Ti3C2Tx electrodes achieve high Coulombic efficiencies (98.8%) for more than 450 cycles at a fixed areal capacity of 1.0 mAh cm−2 with a current density of 1.0 mA cm−2. Moreover, it can maintain stable lithium plating/striping behaviors even at an ultrahigh current density of 5.0 mA cm−2 and high areal capacity of 5.0 mAh cm−2. Furthermore, full batteries (LiFePO4 as cathode) paired with these vertically aligned Ti3C2Tx electrodes show superior stability and rate performance than the horizontally aligned Ti3C2Tx electrodes.

V2O3 Nanoparticles Anchored on an Interconnected Carbon Nanosheet Network Toward High-Performance Sodium-Ion Batteries

“…In addition, COMSOL simulation was performed to investigate the effect of the in situ carbon layer on the Na + flux distribution on the surface of the V 2 O 3 /C electrode. − The poor conductivity and agminated nanoparticles of V 2 O 3 make Na + transport difficult (Figure a). The V 2 O 3 /C nanocomposite benefits from the uniform dispersion of V 2 O 3 nanoparticles on the surface of carbon nanosheets, which makes the distribution of electrochemical reaction more uniform.…”

Applications and Challenges of 2D Materials in Lithium Metal Batteries

“…Copyright 2021, American Chemical Society. (d) Schematic illustrations of Li deposition and surface structure on Li metal anodes with GFNs-PVDF@PP separator and Electrochemical performances of symmetric Li|Li cells with a capacity 3 mAh cm −2 at a current density of 20 mA cm −2 [28] . Copyright 2020, American Chemical Society.…”

“…For example, 2D materials can react with Li during the activate process to form an in-situ protecting layer upon Li metal anode. Xiao et al report a graphite fluoride nanosheets and poly(vinylidene difluoride) modified separator (GFNs-PVDF@PP) to in-situ construct a protective layer for Li metal anodes [28] . In addition, 2D nanomaterials could further improve the mechanical strength of the polymer based artificial SEI layer because of grain refinement effect.…”

Spatially Confined Li Growth on Honeycomb-like Lithiophilic Layered Double Hydroxide Nanosheet Arrays toward a Stable Li Metal Anode

“…Rechargeable metal batteries are of primary concern in the development of next-generation batteries because they can break the bottlenecks of the high-energy-density requirement of portable electronics and electric vehicles. − Especially, the lithium metal anode (LMA) that possesses high specific capacity (3860 mAh g –1 ) and low reduction potential (−3.04 V vs standard hydrogen electrode) is an attractive anode for alkaline metal batteries. − Unfortunately, the practical application of LMA is severely hindered by the uneven Li metal plating/stripping originating from uncontrollable dendrite growth and huge volume expansion. − Moreover, the LMA readily react with electrolyte to form the fragile and inhomogeneous solid electrolyte interphase (SEI) due to its high electrochemical reactivity, thereby exacerbating the nonuniform Li deposition and the growth of dendrites. , As a consequence, lithium metal batteries (LMBs) always suffer from low Coulombic efficiency (CE), rapid cycling capacity decay, and short lifespan. ,, …”