Two types of inorganic/organic hybrids comprising Brønsted acid-base ionic groups have been prepared and studied for proton exchange membranes (PEM) applications. The hybrid membranes have a highly cross-linked silicon-oxygen backbone and trifluoromethanesulfonimide (HTFSI) doped organic amine groups. The Si-O backbone provides the membranes thermal/chemical/mechanical properties and the HTFSI-...

A mixture of tetra-n-butylphosphonium benzimidazolate and benzimidazole is readily prepared as a proton conductive liquid having thermal stability up to 300 °C.

We report here a novel proton exchange membrane with remarkably high methanol-permeation resistivity and excellent proton conductivity enabled by carefully designed self-assembled ionic conductive channels. A direct methanol fuel cell utilizing the membrane performs well with a 20 M methanol solution, very close to the concentration of neat methanol.

Water loss and the coincident increase in membrane resistance to proton conduction are significant barriers to high performance operation of traditional proton exchange membrane fuel cells at elevated temperatures where the relative humidity may be reduced. We report here approaches to the development of high temperature membranes for proton exchange membrane fuel cells; composite perfluorinate...

sulfonated poly (ether ether ketone) (speek) with a low degree of sulfonation (ds = 40%) was prepared for proton exchange membrane fuel cells (pemfc). poly (ether ether ketone) (peek) was sulfonated in concentrated h2so4 under n2 atmosphere and characterized by the hydrogen nuclear magnetic resonance (h-nmr) technique. after preparation of the speek polymer, the obtained polymer was dissolved i...

To suppress methanol crossover in direct methanol fuel cells DMFCs , a Nafion-Bi2V0.75Sb0.25O5.4 composite membrane was prepared by recast method. Oxygen-ion conductive Bi2V0.75Sb0.25O5.4 powders were highly dispersed in a Nafion 117 membrane to physically block methanol crossover and/or chemically oxidize the methanol, which was confirmed by the difference in the methanol diffusion coefficient...

Proton Exchange Membrane (PEM) fuel cells are becoming more popular as an energy conversion device because its efficiency and simplicity in design and operation. Significant improvements and recent developments in the areas of water and heat management, membranes, electrode designs, and, most recently, the interdigitated flow field design, have increased greatly the attractiveness of this syste...

Sulfonated poly (ether ether ketone) (SPEEK) with a low degree of sulfonation (DS = 40%) was prepared for proton exchange membrane fuel cells (PEMFC). Poly (ether ether ketone) (PEEK) was sulfonated in concentrated H2SO4 under N2 atmosphere and characterized by the hydrogen nuclear magnetic resonance (H-NMR) technique. After preparation of the SPEEK polymer, the obtained polymer was dissolved i...