Recent Advances in Non‐nucleophilic Mg Electrolytes

High-performance electrolyte is still a roadblock for the development of rechargeable magnesium (Mg) batteries. Grignard-type electrolytes were once the only choice in the early stage of rechargeable Mg batteries research. However, due to their nucleophilic nature and high reactivity, Grignard-type electrolytes have inherent safety issues and low oxidation stability, which restrict the development of rechargeable Mg batteries in terms of practical application. Recently, emerging novel Mg battery systems such as Mg-S, Mg-O2/air batteries also require non‐nucleophilic electrolytes with high oxidation stability. This short review summarizes recent advances in non‐nucleophilic Mg electrolytes and aims to provide insights into electrochemical properties and active Mg ion structure of such electrolytes.

Influence of ion structure on thermal runaway behaviour of aprotic and protic ionic liquids

Accelerated rate calorimetry has been employed to study the exothermic and thermal runaway behaviour of some aprotic and protic ionic liquids. The aprotic [FSI]− salts are found to be more vulnerable to exothermic decomposition.

Efficient modelling of ion structure and dynamics in inorganic metal halide perovskites

Inorganic metal halide perovskites are nowadays one of the most studied semiconductors. Using quantum calculations as reference data, we have employed a genetic algorithm to develop a force field to study ion migrations and lattice dynamics.

Crystal Polymorphism of 1-Butyl-3-methylimidazolium Hexafluorophosphate: Phase Diagram, Structure, and Dynamics

The ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim]PF6), is one of the most representative ILs. Despite its relatively simple ion structure and popularity, [C4mim]PF6 shows complex and confusing thermal phase behaviours, which stem from crystal polymorphism associated with cation conformational change and large thermal hysteresis. To the best of our knowledge, [C4mim]PF6 is the most investigated IL in terms of phase diagram, whereas full understanding has not yet been achieved due to its complexity. Here we review the current status of understanding of the phase diagram and structure/dynamics of each crystalline phase. Presently, depending on temperature and pressure, five structurally different polymorphic crystals have been reported as α, β, γ, δ, and δ’ in addition to some unspecified phases implied by calorimetric studies. Particularly for the α, β and γ phases, the structure and dynamics are well investigated by Raman, NMR, and X-ray scattering techniques.