A Regularly Channeled Lamellar Membrane for Unparalleled Water and Organics Permeation

Abstract

Lamellar membranes show exceptional molecular permeation properties of key importance for many applications. However, their design and development need the construction of regular and straight interlayer channels and the establishment of corresponding transport rate equation. The fabrication of a uniformly lamellar membrane is reported using double-layered Ti C T MXenes as rigid building blocks. This membrane possesses ordered and straight 2 nm channels formed via a direct self-stacking, in contrast to the conventional irregular ones from flexible sheets. Such channels permit precise molecular rejection and unparalleled molecular permeation. The permeance of water and organics by this membrane reached 2300 and 5000 L m h bar , respectively. The molecular transfer mechanism in confined nanochannels, and the corresponding model equation are established, paving a way to nanoscale design of highly efficient channeled membranes for transport and separation applications.

Elucidating Ultrafast Molecular Permeation through Well‐Defined 2D Nanochannels of Lamellar Membranes

“…While the permeances of nonpolar solvents do not obey this equation (Supporting Information, Figure S29). Interestingly, this is different from the recent model for Ti 3 C 2 T x membrane with 2.0 nm channels: P s =K / δ s η s d s 2 . The inverse‐proportional P s − δ s relation for 2.0 nm channel turns to a positive‐proportional relation for sub‐1.4 nm channel.…”

“…The highly regular nanochannels and tunable channel size of lamellar membranes are further supported by the precise selectivity for dyes (Figure e; Supporting Information, Figures S17–S19, Table S1). Membranes are immersed in dye solutions for 3 h and the UV/Vis absorption spectra display almost no variation before and after immersion (Supporting Information, Figure S17), indicating the negligible adsorption and electrostatic attraction of dyes with membranes . While few dyes form weak electrostatic repulsion with membranes, which would facilitate their rejection to some degree.…”

Combining Silk Sericin and Surface Micropatterns in Bacterial Cellulose Dressings to Control Fibrosis and Enhance Wound Healing

“…16 During the past few years, researches have revealed many encouraging facts and findings regarding the immense potential of graphenebased membranes for separating not only gases but also ions [17][18][19][20][21][22][23][24] and liquids (aqueous/non-aqueous). [25][26][27][28] In this concise review, we provide a brief synopsis of the recent advances in graphenebased gas-separable membranes and the challenges associated for their use as next-generation industrial membranes.…”

2D Laminar Membranes for Selective Water and Ion Transport

“…Unsolved problems and emerging challenges around these topics are then concluded. We note that the knowledge summarized here can also, at least partly, assist the understanding of the selective gas, liquid, and micromolecule transport through laminar membranes, which are gaining considerable attention as well …”