Micelles have been prepared from poly(acrylic acid)-graft-polystyrene by direct injection of a dioxane solution of the polymer into water containing various concentrations of NaCl. The size of the final micelle depends on the polymer concentration in the dioxane solution and the ionic strength of the aqueous phase. A relatively weak dependence of the micelle size on grafting density has been found. TEM images of these micelles reveal a unique “multicore” structure in which small spheres (presumably polystyrene) are associated with intervening polyacid chains that provide the aqueous solubility. It has been found that a very hydrophobic molecule (pyrene) can be solubilized efficiently in water by dissolving it with the polymer in dioxane prior to injection into the water phase. The morphology of the micelles containing pyrene is spherical, according to TEM.

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13 Cobalt-free perovskite-type mixed ionic and electronic conductor (MIEC) is of 14 technological and economic importance in many energy related applications. In this work, a new 15 group of Fe-based perovskite MIEC with BaFe 1-x Gd x O 3-δ (0.025≤x≤0.20) compositions was 16 developed for the application in oxygen permeation membrane. Slight Gd doping (x=0.025) can 17 stabilize the cubic structure of BaFe 1-x Gd x O 3-δ perovskite. The Gd substitution of BaFe 1-x Gd x O 3-δ 18 materials increases the structural and chemical stability in atmosphere containing CO 2 and H 2 O, 19and decreases the thermal expansion coefficient. The BaFe 0.975 Gd 0.025 O 3-δ membrane exhibits fast 20 oxygen surface exchange kinetics and high bulk diffusion coefficient, and achieves a high oxygen 21 2 permeation flux of 1.37 mL cm -2 min -1 for 1 mm thick membrane at 950 o C under Air/He oxygen 1 gradient, which can maintain stable at 900 o C for 100 h. Compared to the pristine BaFeO 3-δ and the 2 well-studied Ba 0.95 La 0.05 FeO 3-δ membranes, lower oxygen permeation activation energy and higher 3 oxygen permeability are obtained for the 2.5 at. % Gd doped material, which might be attributed to 4 the expanded lattice by doping large Gd 3+ cations and limited negative effect from strong Gd-O 5 bond. A combination study of first principle calculation and experimental measurements was 6 further conducted to advance the understanding of Gd effects on oxygen migration behavior in 7BaFe 1-x Gd x O 3-δ . These findings are expected to provide guidelines for the material design of high 8 performance MIECs. 9

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A highly efficient and cost-effective strategy for doping Ca at the B-site of BaFeO3−δ was demonstrated to enhance oxygen permeability.