A rapid and scalable synthesis of six new imine-linked highly porous and crystalline COFs is presented that feature exceptionally high chemical stability in harsh environments including conc. H SO (18 m), conc. HCl (12 m), and NaOH (9 m). This is because of the presence of strong interlayer C-H⋅⋅⋅N hydrogen bonding among the individual layers, which provides significant steric hindrance and a hydrophobic environment around the imine (-C=N-) bonds, thus preventing their hydrolysis in such an abrasive environment. These COFs were further converted into porous, crystalline, self-standing, and crack-free COF membranes (COFMs) with extremely high chemical stability for their potential applications for sulfuric acid recovery. The as-synthesized COFMs exhibit unprecedented permeance for acetonitrile (280 Lm h bar ) and acetone (260 Lm h bar ).

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Transparent conductors and charge transport layers play a key role in the design and fabrication of efficient renewable energy and electronic devices. Over the years, Indium tin oxide (ITO), is...

tivation due to accumulation of P on the catalyst. For example, accumulation and catalytic deactivation. 6947 P from decomposed PH3 diffuses in and out of Pt( 1 1 1) above 300 K and is very difficult to remove by oxidation, espeically at high coverages7 The key to these oxidative processes is the removal of P by PO, formation and desorption before atomic P forms.In a recent study by Smentkowski et al.1° catalytic decomposition of DMMP was observed on Mo(l10) above 898 K in a 2:l 0,-DMMP molecular beam without accumulation of P or C on the surface. The Mo(l10) surface formed a stable oxide layer that catalyzed DMMP decomposition but prevented accumulation and bulk diffusion of P. Our results for DMMP decomposition on a-Fe2039 show that it is active for DMMP decomposition but deactivates as phosphate forms.Unlike Mo, Pt does not readily form a stable bulk oxide. Thus, removal of P can occur only when gas-phase oxygen is present to drive the formation of PO,. In the absence of 02, these PO, species are stable only below 500 K. The dominant PO, species observed in this study is PO. In the absence of 0, it decomposes with an activation barrier of 35.9 kcal/mol, about 23 kcal/mol lower than its desorption barrier from Pt." Thus removal of PO in a catalytic process of Pt will require high temperature to overcome the desorption barrier and high pressures of 0, to maintain P-O bonds. Our results suggest that, in the absence of 02, DMMP decomposition on Pt( 11 1) above 600 K will lead to phosphorus Summary(1) At 100 K on Pt(l1 l), DMMP adsorbs molecularly through the oxygen lone pairs of the -p--O group. This structure is stable to 300 K.(2) TPD after a multilayer exposure of DMMP at 100 K gives multilayer desorption (220 K) and 0.09 ML of DMMP decomposition. The products are 0.27 M L of C O (437, 505, 586 K), 0.79 ML of H2 (340,448, 504 K), surface P, and a small amount of surface C.(3) TPSSIMS results indicate that, between 300 and 500 K, DMMP decomposes in steps to PO,. Near 300 K PO-C bonds cleave, with some P-OC bond cleavage at high-DMMP coverages. At higher temperatures, P-C bonds cleave, leaving at least two PO, species on the surface.(4) The dominant PO, species is PO, which is characterized by a 1255-cm-I u(P=O) loss in HREELS and an intense PO' SSIMS signal. It is stable to at least 500 K. Acknowledgment.Abstract: The effects of substituents at the 0-carbon atom on the donor properties of primary amines and amino alcohols have been studied. Such substituted amino species have important applications in industrially relevant gas-separation processes. Qualitative molecular orbital arguments, along with detailed calculations at the MNDO level of theory, show that upon methyl substitution at the a-carbon atom the interactions of the methyl group orbitals with the nitrogen lone-pair orbital lead to subtle but significant changes in the donor properties of the amino species. Infrared spectroscopic data supporting the calculations are also described. The implications of changes in the donor properties of the amino speci...

High yield amination of GO showing improved dispersion in epoxy resin.