Precise Sub-Angstrom Ion Separation Using Conjugated Microporous Polymer Membranes

Abstract

Polymer membranes typically possess a broad pore-size distribution that leads to much lower selectivity in ion separation when compared to membranes made of crystalline porous materials; however, they are highly desirable because of their easy processability and low cost. Herein, we demonstrate the fabrication of ionsieving membranes based on a polycarbazole-type conjugated microporous polymer using an easy to scale-up electropolymerization strategy. The membranes exhibited high uniform sub-nanometer pores and a precisely tunable membrane thickness, yielding a high ion-sieving performance with a sub-1 Å size precision. Both experimental results and molecular simulations suggested that the impressive ionsieving performance of the CMP membranes originates from their uniform and narrow pore-size distribution.

Carbon nanotube supported oriented metal organic framework membrane for effective ethylene/ethane separation

“…Followed our previously reported procedure ( 38 ), CNT powder (100 mg) and sodium dodecylbenzene sulfonate (1 g) were sonicated in DI water (1 liter) for 1.5 hours. The mixture was centrifuged (15,000 rpm) for 40 min to remove any undispersed CNT powder.…”

Conjugated microporous polymer membranes for light-gated ion transport

“…The membranes made from CMPs by the electropolymerization method in our previous works (27)(28)(29) have shown high porosity, uniform pore size, and impressive molecular/ion transport and sieving performance. In addition, the design of CMP monomers on molecular level could yield immense opportunities for the customization of functionalized membranes (27,28,30,31). The structure and thickness of CMPs membranes can be easily and precisely controlled in nanometer scale by the electropolymerization strategy (27)(28)(29).…”

“…Conjugated microporous polymers (CMPs) are a unique class of porous organic materials with -conjugation structures and intrinsic micropores (23)(24)(25)(26). The membranes made from CMPs by the electropolymerization method in our previous works (27)(28)(29) have shown high porosity, uniform pore size, and impressive molecular/ion transport and sieving performance. In addition, the design of CMP monomers on molecular level could yield immense opportunities for the customization of functionalized membranes (27,28,30,31).…”

“…In addition, the design of CMP monomers on molecular level could yield immense opportunities for the customization of functionalized membranes (27,28,30,31). The structure and thickness of CMPs membranes can be easily and precisely controlled in nanometer scale by the electropolymerization strategy (27)(28)(29). All these advantages make CMPs one of the best candidates as the synthetic materials for the precise construction of smart ion channel membranes.…”

Electropolymerized thin films with a microporous architecture enabling molecular sieving in harsh organic solvents under high temperature

“…39 Tang's group has synthesized CMP lms on indium tin oxide (ITO) and the CMP lm can be transferred to an arbitrary porous support aer etching the ITO surface with diluted HCl solution. 34 Recently, Lai and coworkers reported the electropolymerization of CMPs on carbon nanotubes (CNTs) 41,42 or a polydopamine modied CNT substrate with a highly smooth and porous surface and good adhesion to CMPs. 35 Large-area lms can be fabricated by EP using large-area WEs.…”