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The distribution and dynamics of Li+ ions in β-CD-PEO/Li+ crystalline polymer electrolytes were investigated by 7Li-6Li REDOR NMR and variable-contact-time1H-6Li CP/MAS NMR. [Display omitted] • The distribution and dynamics of the Li+ ions in the crystalline polymer electrolytes (i.e., β-CD-PEO/Li+) were investigated by solid-state NMR. • 7Li-6Li TEDOR NMR was used to correlated the 6Li signals and the 7Li signals. • The 7Li-6Li dipolar couplings measured by 7Li-6Li REDOR provide a way to understand the Li+ spatial density in the samples. • The variable-contact-time cross 1H-6Li CP/MAS NMR was used to probe the dynamics of Li+ ions. • This work demonstrates possible future applications of solid-state NMR on the study of polymer electrolyte. In this work, the distribution and dynamics of Li+ ions in β-CD-PEO/Li+ (β-CD, β-cyclodextrin; PEO, polyethylene-oxides) crystalline polymer electrolytes were investigated by solid-state NMR to enlighten the ionic conduction mechanism. Specifically, 7Li-6Li REDOR NMR and variable-contact-time 1H-6Li CP/MAS NMR were adopted for the study. The results demonstrate that Li+ ions coordinated by polymer chains have relatively compact spatial density and fast dynamics, which facilitate the improvement of the electrochemical properties. Additionally, the variation of the distribution and dynamics of the Li+ ions and the ionic conduction mechanism were studied and discussed by altering the amount of the Li+ ions. This work deepens our understanding of the distribution and dynamics of Li+ ions in β-CD-PEO/Li+ crystals and demonstrates possible future applications of solid-state NMR on the study of the polymer electrolytes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A NMR method having the multiple-targeting signal selectivity was developed. • Optimal control was used to efficiently prepare singlet order of multiple-spin system. • Several targeted molecules and/or chemical groups were probed simultaneously. Selectively probing specific molecules in complex mixtures with nuclear magnetic resonance promises new insights into molecular structures or molecular interaction. Such a study often can be further facilitated when two or more objects in chemical moieties of interest can be precisely targeted. Herein, we proposed a novel method to implement the multiple-targeting signal selection by optimal control of the spin singlets of two or more targeted spin systems from one or more molecules. This method can endow the conventional nuclear magnetic resonance (NMR), magnetic resonance image (MRI) and magnetic resonance spectrum (MRS) with the multiple-targeting signal selectivity to selectively probe several targeted molecules and/or chemical groups simultaneously. [ABSTRACT FROM AUTHOR]