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We characterize a high-capacity cation exchange membrane (CEM) synthesized from an aqueous poly(vinyl alcohol) (PVA) solution and varying amounts of a water-soluble ionic monomer, sodium styrenesulfonate. Highly hydrophilic but waterinsoluble transparent polymers with a range of ion exchange capacities (IECs) can be made; at the high end, the ion exchange capacities (IEC) is >2× that of the benchmark CEM, Nafion. The water uptake of the polymer (as moles of water/mole H + ) is 5−10× greater than that of Nafion. Except at the highest IECs (where steeply increasing water sorption and resultant swelling outpaces IEC increase), the specific conductance increases with increasing IEC while the conductance anisotropy decreases. The material withstands repeated regeneration cycles and hour-long boiling in water or alcohols. The aqueous prepolymer mixture can be cast around a fine wire acting as a mandrel. Fabrication of an ion exchanger microchannel, capable of withstanding at least 300 psi, is demonstrated. We also discuss entirely novel considerations on ab initio limits of conductance of ion exchange membranes.

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In this paper, we conducted comprehensive analysis of the selective adsorption of CO2 by carbon and silicon prismanes along with metal ions. The results of calculations from B3LYP/6-31G(d,p) and M06-2X/6-31G(d,p) levels of theory show that Be[Formula: see text], Mg[Formula: see text], Ca[Formula: see text] and Li[Formula: see text], Na[Formula: see text], K[Formula: see text] ions are bounded strongly enough to prismanes. The Be[Formula: see text] ion binds more strongly to the C8 H8 cubane with binding energy 9.66[Formula: see text]eV compared to Li[Formula: see text], Na[Formula: see text], K[Formula: see text], Mg[Formula: see text] and Ca[Formula: see text] ions having binding energies 1.26, 0.63, 0.51, 4.60 and 3.36[Formula: see text]eV, respectively. Similar results were obtained for larger prismanes C[Formula: see text]H[Formula: see text] and C[Formula: see text]H[Formula: see text]. Instead of binding energy, we determine the adsorption of gases on metal-ion prismane complex along with effect of temperature on different gas adsorption shows that C8H8_Mg[Formula: see text] and C8H8_Be[Formula: see text] are active adsorbents at temperatures above room temperature. It is also observed that in comparison to N2 and CH4, CO2 interacts more strongly with all prismanes decorated with metal ions. These non-covalent interaction plots are used to study the prismane and metal-ion interaction. Comparable study of silicon prismanes with M06 2X/6-31G (d, p) basis set, in terms of binding energy, adsorption of gases on prismane along with temperature effect, also possesses similar selectivity to CO2 molecule with even higher adsorption energies. Thus, beryllium-decorated prismanes can be considered as promising adsorbents of carbon dioxide with good selectivity and high adsorption energy.

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