Complex phenomena are prevalent during the formation of materials, which affect their processing-structure-function relationships. Thin films of methylammonium lead iodide (CH3NH3PbI3, MAPI) are processed by spin coating, antisolvent drop, and annealing of colloidal precursors. The structure and properties of transient and stable phases formed during the process are reported, and the mechanistic insights of the underlying transitions are revealed by combining in situ data from grazing-incidence wide-angle X-ray scattering and photoluminescence spectroscopy. Here, we report the detailed insights on the embryonic stages of organic-inorganic perovskite formation. The physicochemical evolution during the conversion proceeds in four steps: i) An instant nucleation of polydisperse MAPI nanocrystals on antisolvent drop, ii) the instantaneous partial conversion of metastable nanocrystals into orthorhombic solvent-complex by cluster coalescence, iii) the thermal decomposition (dissolution) of the stable solvent-complex into plumboiodide fragments upon evaporation of solvent from the complex and iv) the formation (recrystallization) of cubic MAPI crystals in thin film.

The direct preparation of threo-l,2-glycols without isolation of intermediates from oleic acid, methyl oleate, and oleyl alcohol by oxidation with a hydrogen peroxide (70%)-tmlgstic acid system at pH 0-1 and 45-55C without solvent has now been shown to be an efficient, high-yield reaction.The threo-isomers are formed from intermediate epoxides by in situ hydration with accompanying inversion. Preincorporation of about 2% of the glycol reaction product into oleic acid or methyl oleate speeds up the oxidation reactions markedly and adds to their control and reproducibility. With oleyl alcohol, addition of reaction product is not necessary.Castor and olive oils are also readily oxidized to almost complete elimination of unsaturation, but the products are only 50-60% 1,2-glycols, owing to intra-and intermolecular polyether information. Addition of reaction product is unnecessary with castor oil, but with olive oil the reaction rate is greatly accelerated by incorporation of 2% of reaction product. Preconditioning (5 hr) of the hydrogen peroxide with the tungstie acid permits slightly faster oxidation rates. Emulsions are also rapidly oxidized under appropriate conditions, but these systems are more complicated to prepare and work up than oxidatmn of the substrates directly. Tentative reaction mechanisms are proposed in which an inorganic polyperoxytungstie acid is the effective oxidizing agent and hydroxyl-containing species are intportant interracial or complexing agents between the substrate and oxidant system.

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Sixteen cellulose rich municipal solid waste (MSW) blends were developed and screened using an acidassisted ionic liquid (IL) deconstruction process. Corn stover and switchgrass were chosen to represent herbaceous feedstocks; non-recyclable paper (NRP) and grass clippings (GC) collected from households were chosen as MSW candidates given their abundance in municipal waste streams. The most promising MSW blend: corn stover/non-recyclable paper (CS/NRP) at 80/20 ratio was identified in milliliter-scale screening based on the sugar yield, feedstock cost, and availability. A successful scale-up (600-fold) of the IL-acidolysis process on the identified CS/NRP blend has been achieved. The sugar and lignin streams were recovered and characterized. Mass and material energy flows of the optimized process were presented. Feedstock cost for MSW blends was also discussed. Results suggest the promising potential of using MSW as a feedstock blending agent for biorefineries while maintaining sufficient performance and low feedstock cost. The bench scale (6 L) study is an essential step in demonstrating the scalability of this IL technology.