(497c) Redefining Gas Membrane Fabrication with Paramagnetic 2D Nanomaterials

Over six decades ago, the emergence of polymer membranes sparked a revolution in separation industries. Since then despite numerous advancements in polymer membrane fabrication, a persistent challenge has been the inherent permeability-selectivity trade-off imposed by the polymer structure. To overcome this limitation, innovative approaches have been pursued, notably through the development of mixed matrix membranes. These have demonstrated significant efficacy, with several surpassing the modified 2008 Robenson upper bounds for gas permeation. However, the deposition of these fillers has presented its own set of challenges. Among the various filler materials explored, 2D nanomaterials (NM) have captured the attention of membrane scientists. This is largely due to their ability to be synthesized into atomically thin layers, featuring in-plane selective pores and nanochannel arrays. These properties offer minimal transport resistance and high selectivity. However, the deposition of the nanomaterial itself presents a challenge where the deposition is governed by innate host-particle interaction. To truly break the permeability-selectivity trade-off, it becomes imperative to introduce external forces to regulate deposition. In this regard, magnetized filler materials emerge as a promising solution. By harnessing external magnetic forces, precise control over deposition can be achieved, offering a pathway to enhance membrane performance and transport channels. In our work, we focus on the fabrication of mixed matrix membranes with paramagnetic 2D nanomaterials. PSF commercial polymer is chosen as the matrix phase. The synthesized paramagnetic 2D materials only experience magnetism when subjected to an external magnetic field. Leveraging the paramagnetic characteristic, we developed "Magnetophoretic Membrane Fabrication" method. We evaluated the performance of our fabricated membranes through single gas permeation tests (H2= 0.289nm, CO2=0.330nm, CH4= 0.380nm) using the constant volume variable pressure method. This innovative approach enables control over the deposition of the paramagnetic 2D nanomaterials. Through the integration of magnetism into the membrane fabrication process, we anticipate overcoming significant hurdles in membrane science and technology.