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Lithium metal as an anode has been widely accepted due to its higher negative electrochemical potential and theoretical capacity. Nevertheless, the existing safety and cyclability issues limit lithium metal anodes from practical use in high-energy density batteries. Repeated Li deposition and dissolution processes upon cycling lead to the formation of dendrites at the interface which results in reduced Li availability for electrochemical reactions, disruption in Li transport through the interface and increased safety concerns due to short circuiting. Here, we demonstrate a novel strategy using Ionic Liquid Crystals (ILCs) as the electrolyte cum pseudo-separator to suppress dendrite growth with their anisotropic properties controlling Li-ion mass transport. A thermotropic ILC with two-dimensional Li-ion conducting pathways was synthesized and characterized. Microscopic and spectroscopic analyses elucidate that the ILC formed with a smectic A phase, which can be utilized for wide temperature window operation. The results of electrochemical studies corroborate the efficacy of ILC electrolytes in mitigating dendrite formation even after 850 hours and it is further substantiated by numerical simulation and the mechanism involved in dendritic suppression was deduced. 

We report a simple ambient pressure annealing technique for the synthesis of ultrathin niobium disulfide (NbS 2 ) nanoflakes. The structure, morphology and composition of the as-synthesized NbS 2 flakes are well characterized using various microscopic and spectroscopic techniques. The synthesized two-dimensional layered NbS 2 is in stoichiometric proportion, and has a single crystal 3R-NbS 2 polymorph structure with semiconducting behavior and has abundant catalytic defect sites. In this paper, the hydrogen evolution reaction (HER) activity of the NbS 2 nanoflakes/rGO composite having dense exposed basal planes with improved conductivity is explored, and it is found to be a good HER catalyst in terms of low onset potential, low Tafel slope and high exchange current density.