The influence of the functional group density on gas flow and selectivity: Nanoscale interactions in alkyl-functionalized mesoporous membranes

Locating Reactive Groups on Nanomaterials with Gold Nanoclusters: Toward a Surface Reactive Site Map

“…For the differently functionalized and AuNC-mapped SiNPs, a circular region with a diameter of 60–70 nm was selected such that the edge of the SiNPs was avoided and a maximum 10 nm distance was kept from the periphery of the SiNPs, where the projection error is largest (Figure S11). The same procedure was used in a recent theoretical study by Besser et al Figure C,D show measurements of three individually mapped SiNPs and the application of a minimum of 100 distance measurements per object. The distance measurements and standard deviations verify that as the concentration of the functional groups increases, the distance between AuNCs decreases from approximately 5 ± 0.3 to 2.8 ± 0.4 nm for thiolated SiNPs and from approximately 14.5 ± 2 to 3.1 ± 0.7 nm for aminated SiNPs, corresponding to the relative distance between the reactive functional groups and hence confirming the increasing surface density of the functional groups on SiNPs.…”

“…For the differently functionalized and AuNC-mapped SiNPs, a circular region with a diameter of 60 -70 nm was selected such that the edge of the SiNPs was avoided and a maximum of 10 nm distance was kept from the periphery of the SiNPs where the projection error is largest ( Figure S10). The same procedure was used in recent theoretical study by Besser et al 37 Figure 3C and D show measurements of three individually mapped SiNPs and applying a minimum of 100 distance measurements per object. The distance measurements and standard deviations verify that as the concentration of the functional groups increases, the distance between each AuNCs decreases from approx.…”

“…A similar dependency of functional group distances was also reported in the theoretical study of Besser et al when considering random arrangement of the functional groups. 37 The shaded region in the Figure 3C and D represents the standard deviation between distances measured on a single particle. The maximal deviation narrows down from about 4.5 to 2.0 nm for thiolated SiNPs and from 25.7 to 2.2 nm for aminated SiNPs on average indicating the decreasing distance of AuNCs.…”

Influence of solvent, Lewis acid–base complex, and nanoparticles on the morphology and gas separation properties of polysulfone membranes

“…The significant features of a polymeric membrane are permeability and selectivity, which depend on its physicochemical properties. [ 15–18 ] For instance, in contrast to glassy polymers, in rubbery polymers, the fractional free volume (FFV) increases with decreasing glass transition temperature ( T g ), which results in permeability enhancement. [ 19,20 ] Besides, the solvents used for the preparation of polymer‐based membranes, due to the differences in their molecular size, boiling temperature, and interactions with polymer chains, have a major effect on the separation performance and morphology of these membranes.…”

Determination of maximum possible contribution of porous particles in gas transport properties of their corresponding mixed matrix membranes

“…Variation in geometry, functional groups, and synthesis conditions of porous particles usually result in a significant difference in their gas separation properties. [31][32][33][34][35][36] Moreover, as pinholes might be formed during the preparation of inorganic membranes, [37] measurement of their intrinsic permeability can be error-prone. In addition to the connectivity of pores, separation properties of the particles are affected by pore size and surface area of the porous particles.…”