Influence of different perfluorinated anion based Ionic liquids on the intrinsic properties of Nafion®

Mixed-Matrix Membranes Based on Polyetherimide, Metal–Organic Framework and Ionic Liquid: Influence of the Composition and Morphology on Gas Transport Properties

In this work, membranes based on polyetherimide (PEI), a ZIF-8 metal–organic framework and 1-ethyl-methylimidazolium tetrafluoroborate ionic liquid (IL) were prepared. IL and ZIF-8 contents amounting to 7 wt% and 25 wt%, respectively, were investigated. CO₂, He and H₂ transport properties of PEI/IL/ZIF-8 membranes were compared to those obtained for the respective PEI/ZIF-8 and PEI/IL systems. Membranes’ gas permeability and selectivity are discussed as a function of the membrane composition and morphology, and they were assessed in relation to existing experimental and theoretical data from the literature. Promising gas transport properties were obtained using the appropriate combination of ZIF-8 and IL amounts in the PEI matrix. Indeed, an increase in the CO₂ permeability coefficient by a factor of around 7.5 and the He and H₂ permeability coefficients by a factor of around 4 was achieved by adding 7 wt% IL and 10 wt% ZIF-8 to the PEI matrix. Moreover, diffusion was evidenced as a governing factor in the studied membrane series.

Performance evaluation of microbial electrochemical systems operated with Nafion and supported ionic liquid membranes

In this work, the performance of dual-chamber microbial fuel cells (MFCs) constructed either with commonly used Nafion^® proton exchange membrane or supported ionic liquid membranes (SILMs) was assessed. The behavior of MFCs was followed and analyzed by taking the polarization curves and besides, their efficiency was characterized by measuring the electricity generation using various substrates such as acetate and glucose. By using the SILMs containing either [C₆mim][PF₆] or [Bmim][NTf₂] ionic liquids, the energy production of these MFCs from glucose was comparable to that obtained with the MFC employing polymeric Nafion^® and the same substrate. Furthermore, the MFC operated with [Bmim][NTf₂]-based SILM demonstrated higher energy yield in case of low acetate loading (80.1 J g^-1 COD_in m^-2 h^-1) than the one with the polymeric Nafion^® N115 (59 J g^-1 COD_in m^-2 h^-1). Significant difference was observed between the two SILM-MFCs, however, the characteristics of the system was similar based on the cell polarization measurements. The results suggest that membrane-engineering applying ionic liquids can be an interesting subject field for bioelectrochemical system research.