The Role of High‐Gradient Diffusion Nuclear Magnetic Resonance in Exploring Peculiarity of Water in Ionic Liquids Doped with Alkali Metals

Ternary mixtures based on ionic liquids (IL), water, and alkali halides (MX) are emerging as greener alternatives to lithium‐ion electrolytes. Consequently, a question arises about the possible influence of M + cations on the structural heterogeneities in the IL solvent network, formed in the presence of water. This study employs nuclear magnetic resonance methodologies, such as high‐gradient diffusion measurements, to provide an in‐depth understanding of the nearest environment of Na + in the EMIM‐BF 4 ‐H 2 O‐NaCl pilot solution. The results reveal a strong dependence between the number of water molecules in the first solvation shell of sodium and the formation of the polar nanodomains in the IL. The EMIM‐BF 4 :H 2 O molecular ratio, previously reported as the most significant parameter governing the structural arrangement of binary IL‐water systems, becomes of lower importance in the presence of small concentrations of sodium halides. Thus, even minor changes in the IL solutions may lead to significant modifications in their behavior, potentially expanding the range of applications.