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Keywords: pseudo-one dimensional materials, gallium telluride, physical vapor transport.Pseudo-one dimensional (pseudo-1D) materials are new-class of materials where atoms are arranged in chain like structures in two-dimensions (2D). Examples to these materials include recently discovered black phosphorus (BPs) [1,2] , ReS2 and ReSe2 from transition metal dichalcogenides (TMDCs) [3][4][5] , TiS3 and ZrS3 from transition metal trichalcogenides (TMTCs) [6, 7, 8, 9] and most recently GaTe [10] . The presence of structural anisotropy impacts their physical properties and leads to direction dependent light-matter interactions [3,5] , dichroic optical responses [8] , high mobility channels [2] , and anisotropic thermal

This study examines the role that silica nanoparticles play on the permeation of methane, ethane, and propane gases through two types of polyurethane (PU) membranes: one based on polyether and the other based on polyester. These PU membranes are synthesized from polycaprolactone (PCL225) polyester and polypropylene glycol (PPG) polyether in a 1–3–2 mol ratio of polyol/hexamethylenediisocyanate/1,4-butane diol. The prepared PU-silica membranes are characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and wide-angle X-ray diffraction (WAXD) analyses. The characterization analyses confirmed the nanoscale distribution of silica particles within the polymer matrix. Permeation experiments reveal that in polyether-based PU, permeability first increases by increasing silica content up to 2.5%, and then decreases. The permeability of gases in polyester-based PU constantly decreases by increasing silica nanoparticle loading. The selectivity for C3H8 over methane increases with the inclusion of silica particles in the polyether-based PU membranes, while it decreases in polyester-based PU membranes. Our results indicate high propane permeability and propane/methane selectivity of polyether-based mixed matrix membranes (MMMs) containing 12.5% silica at 2 bar pressure up to, 118 barrer and 7.01, respectively.

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This paper reports the effects of synthesis time, temperature, and reactant ratio on ZIF-71 particle size and the effect of particle size on membrane performance. Temperature has the greatest effect on particle size, as the synthesis temperature varies from −20 °C to 35 °C. The synthesized ZIF-71 has particle diameters ranging from 150 nm to 1 μm. ZIF-71 particle size is critical in ZIF-71/PDMS composite membrane performance for ethanol and 1-butanol removal from water through pervaporation. The membranes that are made with micrometer-sized ZIF-71 particles exhibit higher alcohol/ water selectivity than those with smaller particles. Both alcohol and water permeability increase when larger-sized ZIF-71 particles are incorporated, because the pathways through the membranes are less tortuous.