Electropolymerization of robust conjugated microporous polymer membranes for rapid solvent transport and narrow molecular sieving

Abstract

Pore size uniformity is one of the most critical parameters in determining membrane separation performance. Recently, a novel type of conjugated microporous polymers (CMPs) has shown uniform pore size and high porosity. However, their brittle nature has prevented them from preparing robust membranes. Inspired by the skin-core architecture of spider silk that offers both high strength and high ductility, herein we report an electropolymerization process to prepare a CMP membrane from a rigid carbazole monomer, 2,2’,7,7’-tetra(carbazol-9-yl)-9,9’-spirobifluorene, inside a robust carbon nanotube scaffold. The obtained membranes showed superior mechanical strength and ductility, high surface area, and uniform pore size of approximately 1 nm. The superfast solvent transport and excellent molecular sieving well surpass the performance of most reported polymer membranes. Our method makes it possible to use rigid CMPs membranes in pressure-driven membrane processes, providing potential applications for this important category of polymer materials.

Gadolinium-Coated Mesoporous Silica Nanoparticle for Magnetic Resonance Imaging

“…Both surface area and pore distribution are critical for evaluating mesoporous materials; thus, all of the N 2 adsorption–desorption isotherms of Gd 2 O 3 @MSN using BJH ( Figures 4A,B ) were evaluated. The samples exhibit typical type IV curves with an evident hysteresis loop, confirming its mesoporous nature ( López et al, 2006 ; Liu et al, 2015 ; Philippart et al, 2017 ; Francesca et al, 2018 ; Naseem et al, 2020 ; Zhou et al, 2020 ). The BET test results also suggest that the surface area of the MSN was around 822.96 m 2 /g, making them much larger than previous versions of similar compounds ( Shao et al, 2011 ).…”

Electropolymerization of Metal Clusters Establishing a Versatile Platform for Enhanced Catalysis Performance

“…Electrochemical oxidative coupling of metal NCs were firstly confirmed by CV curves (Figure 1d). The first cycle of the positive scan exhibited two oxidation peaks at 1.14 and 1.66 V vs. Ag + /AgCl, which can be assigned to the oxidation of copper center and carbazole moieties, [7a,g] respectively. On the subsequent negative scan, the appearance of two obvious reductive peaks at 0.68 and 1.11 V vs. Ag + /AgCl originate from two successive one‐electron reductions of the dimeric carbazole reduce to its neutral state [7g] .…”

“…The first cycle of the positive scan exhibited two oxidation peaks at 1.14 and 1.66 V vs. Ag + /AgCl, which can be assigned to the oxidation of copper center and carbazole moieties, [7a,g] respectively. On the subsequent negative scan, the appearance of two obvious reductive peaks at 0.68 and 1.11 V vs. Ag + /AgCl originate from two successive one‐electron reductions of the dimeric carbazole reduce to its neutral state [7g] . Along with increasing the scan cycles, both anodic and cathodic currents constantly increased, illustrating gradual deposition of Poly‐Cu 14 cba on the electrode [7a,b,e,g] .…”

“…And the adsorption intensities of the poly‐metal NCs gradually enhanced as the CV scan numbers increased (Figure S4). Further structural proof of polymerized metal NCs come from Fourier transform infrared (FT‐IR) spectra with the appearance of the characteristic C−H vibrational band of the tri‐substituted carbazole ring (801 cm −1 ) as well as the disappearance of the disubstituted carbazole ring (720 cm −1 ) (Figure S5), suggesting formation of the biscarbazole network [7b,c,e,g] . In addition, the obtained Poly‐Cu 14 cba membrane is insoluble in most organic solvents, such as CH 3 CN, CH 2 Cl 2 , DMF and THF.…”

Controllable Synthesis of Conjugated Microporous Polymer Films for Ultra-sensitive Detection of Chemical Warfare Agents

“…Further, π-skeletons facilitate the exciton delocalization resulting in a "molecular wire effect" that is better able to amplify the uorescence response signals and thus enhancing sensing sensitivity, compared with small molecular materials 24 . However, the lm processability of CMPs limited by their poor solubility is the bottleneck issue in their practical applications 25 . Indeed, most studied uorescence CMPs are insoluble solids that are unsuitable for sensor integration 26 .…”