Nanoconfinement enabled non-covalently decorated MXene membranes for ion-sieving.

Covalent modification is commonly used to tune the channel size and functionality of 2D membranes. However, common synthesis strategies used to produce such modifications are known to disrupt the structure of the membranes. Herein, we report less intrusive yet equally effective non-covalent modifications on TiCT MXene membranes by a solvent treatment, where the channels are robustly decorated by protic solvents via hydrogen bond network.

High-Performance Magnesium Electrochemical Cycling with Hybrid Mg-Li Electrolytes.

Kinetics and coulombic efficiency of the electrochemical magnesium plating and stripping processes are to a significant extent defined by the composition of the electrolyte solution, optimization of which presents a pathway for improved performance. Adopting this strategy, we undertook a systematic investigation of the Mg process in different combinations of the Mg-Li-borohydride-bis(trifluoromethylsulfonyl)imide (TFSI) electrolytes in 1,2-dimethoxyethane (DME) solvent. Results indicate that the presence of BH is essential for high coulombic efficiency, which coordination to Mg was confirmed by Raman and NMR spectroscopic analysis.

High-Performance Cycling of Na Metal Anodes in Phosphonium and Pyrrolidinium Fluoro(sulfonyl)imide Based Ionic Liquid Electrolytes.

We have investigated the sodium electrochemistry and the evolution and chemistry of the solid-electrolyte interphase (SEI) upon cycling Na metal electrodes in two ionic liquid (IL) electrolytes. The effect of the IL cation chemistry was determined by examining the behavior of a phosphonium IL (PFSI) in comparison to its pyrrolidinium-based counterpart (CmpyrFSI) at near-saturated NaFSI salt concentrations (superconcentrated ILs) in their dry state and with water additive. The differences in their physical properties are reported, with the PFSI system having a lower viscosity, higher conductivity, and higher ionicity in comparison to the CmpyrFSI-based electrolyte, although the addition of 1000 ppm (0.