Ionic liquid dynamics and electrical conductivity under confinement within micro and nanocellulose ionogels

Abstract

AbstractTo investigate the effect of cellulose matrix on the diffusion and conductivity properties of the ionogels formed with the BMIMCl ionic liquid (IL), two types of samples were made with micro (CMC) and nano (CNC) cellulose. The cellulose interactions with IL were studied by 1H and 13C NMR solid-state spectroscopy. The cation [BMIM]+ self-diffusion coefficient was calculated based on Fast Field Cycling 1H NMR relaxation measurements. The ionic conductivity was measured by the thermal scanning conductometry method. The NMR spectra at room temperature revealed that cation in the CNC-based ionogel interacts more strongly with the cellulose chain than in the CMC-based ionogel through the methyl group at the end of the alkyl chain. Despite this, the cellulose matrix's influence on the cations' dynamics and electrical conductivity are comparable in both ionogels. The diffusion coefficient is reduced by about two times and the conductivity by about 30% compared with bulk IL.