Carrio Juan A G, Talluri Vssl Prasad, Toolahalli Swamy T, Echeverrigaray Sergio G, Castro Neto Antonio H
Centre for Advanced 2D Materials, National University of Singapore, Singapore 117546, Singapore.
Centre for Hydrogen Innovations, National University of Singapore, E8, 1 Engineering Drive 3, Singapore 117580, Singapore.
Membranes (Basel). 2025 Jan 15;15(1):31. doi: 10.3390/membranes15010031.
The large-scale implementation of 2D material-based membranes is hindered by mechanical stability and mass transport control challenges. This work describes the fabrication, characterisation, and testing of self-standing graphene oxide (GO) membranes cross-linked with oxides such as FeO, AlO, CaSO, NbO, and a carbide, SiC. These cross-linking agents enhance the mechanical stability of the membranes and modulate their mass transport properties. The membranes were prepared by casting aqueous suspensions of GO and SiC or oxide powders onto substrates, followed by drying and detachment to yield self-standing films. This method enabled precise control over membrane thickness and the formation of laminated microstructures with interlayer spacings ranging from 0.8 to 1.2 nm. The resulting self-standing membranes, with areas between 0.002 m and 0.090 m and thicknesses from 0.6 μm to 20 μm, exhibit excellent flexibility and retain their chemical and physical integrity during prolonged testing in direct contact with ethanol/water and methanol/water mixtures in both liquid and vapour phases, with stability demonstrated over 24 h and up to three months. Gas permeation and chemical characterisation tests evidence their suitability for gas separation applications. The interactions promoted by the oxides and carbide with the functional groups of GO confer great stability and unique mass transport properties-the NbO cross-linked membranes present distinct performance characteristics-creating the potential for scalable advancements in cross-linked 2D material membranes for separation technologies.
基于二维材料的膜的大规模应用受到机械稳定性和传质控制挑战的阻碍。这项工作描述了与FeO、AlO、CaSO、NbO等氧化物以及碳化物SiC交联的自立式氧化石墨烯（GO）膜的制备、表征和测试。这些交联剂增强了膜的机械稳定性并调节了它们的传质特性。通过将GO和SiC或氧化物粉末的水悬浮液浇铸到基材上，然后干燥和分离以得到自立式薄膜来制备膜。这种方法能够精确控制膜的厚度，并形成层间距为0.8至1.2nm的层状微结构。所得的自立式膜面积在0.002平方米至0.090平方米之间，厚度为0.6μm至20μm，具有出色的柔韧性，并且在与乙醇/水和甲醇/水混合物在液相和气相中直接接触的长时间测试过程中保持其化学和物理完整性，稳定性在24小时至三个月内得到证明。气体渗透和化学表征测试证明了它们适用于气体分离应用。氧化物和碳化物与GO官能团之间的相互作用赋予了极大的稳定性和独特的传质特性——NbO交联膜呈现出独特的性能特征——为用于分离技术的交联二维材料膜的可扩展进展创造了潜力。
