MXenes and Other Two-Dimensional Materials for Membrane Gas Separation: Progress, Challenges, and Potential of MXene-Based Membranes

Abstract

Gas separation membranes incorporating twodimensional (2D) materials have received considerable attention in recent years, as these membranes have shown outstanding physical, structural, and thermal properties and high permeabilityselectivity. The reduced thickness and diversity of the gas transport mechanisms through in-plane pores (intrinsic defects), in-plane slitlike pores, or plane-to-plane interlayer galleries provide the membranes with a significant sieving ability for energy-efficient gas separation. The discovery of 2D transition metal carbides/nitrides materials, MXenes, has provided new opportunities in the gas separation membrane area because of their hydrophilicity, rich chemistry, high flexibility, and mechanical strength. This Review puts into perspective recent advances in 2D-material-based gas separation membranes. It discusses research opportunities mainly in MXene-based gas membranes, highlights modification approaches for tuning the in-plane and plane-to-plane nanoslits, explains governing mechanisms of transport through these membranes, and compares their advantages and disadvantages with those of other 2D materials. It also discusses current challenges and provides prospects in this area.

Can MXene be the Effective Nanomaterial Family for the Membrane and Adsorption Technologies to Reach a Sustainable Green World?

“…Since the MXene nanomaterial family provides outstanding physicochemical and structural properties, it attracted considerable attention in different applications. Therefore, several critical reviews have been published dominantly focusing on its separation applications. ,,,,− However, most of them could not cover such a large number of separation applications and aimed to concentrate on specifically either the membrane ,− or adsorption ,− based separation processes. However, there are comprehensive review studies covering the potential of MXene membranes and adsorbents for a single separation application such as pervaporation, gas separation, − desalination, ,, dye removal, , oil-in-water separation, removal of heavy metal ions, and radionuclides. ,− On the other hand, few studies ,, aimed to highlight the effect of several strategies such as various surface modification approaches of MXene, intercalation methods to enhance interlayer distance of MXene nanochannels, etc.…”

“… 86 , 90 , 91 , 94 , 100 − 124 However, most of them could not cover such a large number of separation applications and aimed to concentrate on specifically either the membrane 90 , 100 − 102 or adsorption 94 , 103 − 108 based separation processes. However, there are comprehensive review studies covering the potential of MXene membranes and adsorbents for a single separation application such as pervaporation, 109 gas separation, 110 − 112 desalination, 86 , 113 , 114 dye removal, 91 , 115 oil-in-water separation, 116 removal of heavy metal ions, and radionuclides. 115 , 117 − 120 On the other hand, few studies 108 , 121 , 122 aimed to highlight the effect of several strategies such as various surface modification approaches of MXene, intercalation methods to enhance interlayer distance of MXene nanochannels, etc.…”

Advancements in defect engineering of two-dimensional nanomaterial-based membranes for enhanced gas separation

“…13 To surmount this limitation and achieve efficient gas separation, the focus has shifted towards exploring novel membrane materials, including zeolites, 14 metal-organic frameworks (MOFs), 15 covalent organic frameworks (COFs), 16,17 hybrid-based composite materials, 18 thermally rearranged polymers, 19 and twodimensional nanomaterials. [20][21][22] Particularly, two-dimensional nanomaterials, with their atomic-scale thickness, extensive surface area, and robust Young's modulus, are increasingly viewed as the most promising candidates for developing membranes with high permeability and selectivity. These materials can be oriented flatly or vertically within membranes, allowing the formation of nanogaps through the stacking of adjacent nanosheets.…”

Editorial for the Festschrift Honoring the Legacy of Babatunde A. Ogunnaike (1956–2022)

“…The Festschrift also includes several contributions that focus on materials science and engineering, such as the paper of Zhu et al., who report on the preparation of high-strength SBR vitrimers, Isfahani et al, reviewing the use of two-dimensional materials (such as MXenes) for membrane gas separations, and Schork, who provides a perspective on the commercialization of microemulsion technology . Percival et al discuss the durability and cycling of impedance NO 2 sensors based on nanoporous materials .…”