Self-diffusion of phosphonium Bis(Salicylato)Borate ionic liquid in pores of Vycor porous glass
2016 (English)In: Microporous and Mesoporous Materials, ISSN 1387-1811, E-ISSN 1873-3093, Vol. 230, 128-134 p.Article in journal (Refereed) PublishedText
H-1 NMR pulsed field gradient was used to study self-diffusion of a phosphonium bis(salicylato)borate ionic liquid ([P6,6,6,14][BScB]) in the pores of Vycor porous glass at 296 K. Confinement in pores increases diffusion coefficients of the ions by a factor of 35. However, some [P6,6,634][BScB] ions demonstrated apparent diffusion coefficients much lower than their mean values, which may be due to partially restricted diffusion of the ions. We suggest that this fraction corresponds to areas where ions are confined by pore 'necks' (micropores) and empty voids. Heating of the ionic liquid/Vycor system at 330 K led to a change in the diffusivity of the ions, because of their redistribution in the pores. The size of the bounded regions is on the order of 1 mu m, as estimated from the dependence of the ion diffusivity on the diffusion time.
Place, publisher, year, edition, pages
2016. Vol. 230, 128-134 p.
Nuclear magnetic resonance, Pulsed-field gradient, NMR diffusometry, Restricted diffusion, Confined liquid, Translational mobility
IdentifiersURN: urn:nbn:se:kth:diva-189909DOI: 10.1016/j.micromeso.2016.04.044ISI: 000378661100015ScopusID: 2-s2.0-84968542987OAI: oai:DiVA.org:kth-189909DiVA: diva2:950372
QC 201607292016-07-292016-07-252016-07-29Bibliographically approved