Enhanced proton transport in nanostructured polymer electrolyte/ionic liquid membranes under water-free conditions

Abstract

Proton exchange fuel cells (PEFCs) have the potential to provide power for a variety of applications ranging from electronic devices to transportation vehicles. A major challenge towards economically viable PEFCs is finding an electrolyte that is both durable and easily passes protons. In this article, we study novel anhydrous proton-conducting membranes, formed by incorporating ionic liquids into synthetic block co-polymer electrolytes, poly(styrenesulphonate-b-methylbutylene) (s n mB m ), as high-temperature PEFCs. The resulting membranes are transparent, flexible and thermally stable up to 180 °C. The increases in the sulphonation level of s n mB m co-polymers (proton supplier) and the concentration of the ionic liquid (proton mediator) produce an overall increase in conductivity. morphology effects were studied by X-ray scattering and electron microscopy. Compared with membranes having discrete ionic domains (including nafion 117), the nanostructured membranes revealed over an order of magnitude increase in conductivity with the highest conductivity of 0.045 s cm − 1 obtained at 165 °C.

Facile Anhydrous Proton Transport on Hydroxyl Functionalized Graphane

“…The mechanism of PT in aqueous systems has been extensively studied and is well understood. In contrast, the PT mechanisms under anhydrous conditions appear to depend on the material and are a matter of debate [5][6][7][8]. This work provides atomic-level insight into how PT takes place on OH-functionalized graphane and why the barriers to PT on this material are so low.…”

Fast low-voltage electroactive actuators using nanostructured polymer electrolytes

“…A poly(styrene-b-methylbutylene) (PS-b-PMB, 16.8-18.7 kg mol À 1 ) copolymer was synthesized by sequential anionic polymerization of styrene and isoprene monomers followed by selective hydrogenation of isoprene units 51 . The molecular weight and molecular weight distribution of the PS-b-PMB copolymer were characterized by combining 1 H-NMR (Bruker AVB-300) spectroscopy and gel permeation chromatography (Waters Breeze 2 HPLC).…”

“…The styrene chains of PS-b-PMB copolymer were then partially sulphonated using procedures described in ref. 51, which were referred to as PSS-b-PMB block copolymers. Samples with different SL were prepared by controlling reaction time; SL ¼ 20 mol% with 0.3 h reaction, SL ¼ 30 mol% with 0.5 h reaction and SL ¼ 75 mol% with 30 h reaction.…”

“…One-hundred-micrometre-thick membranes were prepared by solvent casting onto an aluminum mold (an area of 1 cm  1.5 cm) at room temperature under an argon atmosphere for 2 days followed by vacuum drying at 70°C for 7 days. The dried polymer membrane was subjected to a normal stress of about 200 kgf cm À 2 in a hydraulic Carver press at 25°C for 12 h to yield dominant parallel orientation of hexagonal cylinder microdomains 51,52 . The polymer membranes were then sandwiched between two SWCNTs electrodes via hot pressing, which yields a monolithic trilaminar structure.…”

More sustainable electricity generation in hot and dry fuel cells with a novel hybrid membrane of Nafion/nano-silica/hydroxyl ionic liquid

“…Alternatively, the proton conduction in Nafion and other sulfonated polymers can be sustained at temperatures above 150 o C by blending these polymers with non-volatile, thermally stable ionic liquids (ILs) that were reported to have anhydrous ionic conductivities exceeding 10 -2 S cm -1 [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. However, up until now, the validation of sulfonated polymer/IL PEMs in H 2 -O 2 FCs has been disappointing.…”