Cross-linkable, phosphobetaine-based, zwitterionic amphiphiles that form lyotropic bicontinuous cubic phases Lauren N. Bodkin, Zachary A. Krajnak, Ruiqi Dong, Chinedum O. Osuji, Douglas L. Gin Soft Matter, 2023 Two new, cross-linkable, phosphobetaine zwitterionic amphiphiles were found to form a type II bicontinuous cubic (QII) phase with aq. NH4Cl. Upon polymerization, they form 3D-nanoporous membrane materials that are not susceptible to ion exchange.
Tunable organic solvent nanofiltration in self-assembled membranes at the sub-1 nm scale Yizhou Zhang, Dahin Kim, Ruiqi Dong, Xunda Feng, Chinedum O. Osuji Science Advances, 2022 Organic solvent–stable membranes exhibiting strong selectivity and high permeance have the potential to transform energy utilization in chemical separation processes. A key goal is developing materials with uniform, well-defined pores at the 1-nm scale, with sizes that can be tuned in small increments with high fidelity. Here, we demonstrate a class of organic solvent–stable nanoporous membranes derived from self-assembled liquid crystal mesophases that display such characteristics and elucidate their transport properties. The transport-regulating dimensions are defined by the mesophase geometry and can be controlled in increments of ~0.1 nm by modifying the chemical structure of the mesogen or the composition of the mesophase. The highly ordered nanostructure affords previously unidentified opportunities for the systematic design of organic solvent nanofiltration membranes with tailored selectivity and permeability and for understanding and modeling rejection in nanoscale flows. Hence, these membranes represent progress toward the goal of enabling precise organic solvent nanofiltration.
Two-Photon Laser Microprinting of Highly Ordered Nanoporous Materials Based on Hexagonal Columnar Liquid Crystals Joël Monti, Alberto Concellón, Ruiqi Dong, Mira Simmler, Alexander Münchinger, et al. ACS Applied Materials and Interfaces, 2022 Nanoporous materials relying on supramolecular liquid crystals (LCs) are excellent candidates for size- and charge-selective membranes. However, whether they can be manufactured using printing technologies remained unexplored so far. In this work, we develop a new approach for the fabrication of ordered nanoporous microstructures based on supramolecular LCs using two-photon laser printing. In particular, we employ photo-cross-linkable hydrogen-bonded complexes, that self-assemble into columnar hexagonal (Colh) mesophases, as the base of our printable photoresist. The presence of photopolymerizable groups in the periphery of the molecules enables the printability using a laser. We demonstrate the conservation of the Colh arrangement and of the adsorptive properties of the materials after laser microprinting, which highlights the potential of the approach for the fabrication of functional nanoporous structures with a defined geometry. This first example of printable Colh LC should open new opportunities for the fabrication of functional porous microdevices with potential application in catalysis, filtration, separation, or molecular recognition.
Nanocomposites of 2D-MoS2Exfoliated in Thermotropic Liquid Crystals Uri R. Gabinet, Changyeon Lee, Ryan Poling-Skutvik, Daniel Keane, Na Kyung Kim, et al. ACS Materials Letters, 2021 Atomically thin MoS2 nanosheets are of interest due to unique electronic, optical, and catalytic properties that are absent in the bulk material. Methods to prepare nanosheets from bulk material th...
