Pebax‐Based Membrane Filled with Two‐Dimensional Mxene Nanosheets for Efficient CO₂ Capture

Abstract

Mixed matrix membranes (MMMs) made from inorganic fillers and polymers is a kind of promising candidate for gas separation. In this work, two‐dimensional MXene nanosheets were synthesized and incorporated into a polyether‐polyamide block copolymer (Pebax) matrix to fabricate MMM for CO2 capture. The physicochemical properties of MXene nanosheets and MXene/Pebax membranes were studied systematically. The introduction of MXene nanosheets provided additional molecular transport channels and meanwhile enhanced the CO2 adsorption capacity, thereby enhancing both the CO2 peremance and CO2/N2 selectivity of Pebax membrane. The optimized MXene/Pebax membrane with a MXene loading of 0.15 wt % displayed a high separation performance with a CO2 permeance of 21.6 GPU and a CO2/N2 selectivity of 72.5, showing potential application in CO2 capture.

PrestructuredMXenefillers with uniform channels to enhanceCO2selective permeation in mixed matrix membranes

“…Recently, "MXenes", a newly discovered 2D materials, received tremendous attention because of great conductivity and the easily obtained multilayered structure. [19][20][21][22] These materials are often gained from MAX phase, in which M represents transition metal, A is from boron or carbon family elements and X responds to C or N. By removing the A group from MAX phase, the M n + 1 X n T x is produced. An obvious advantage of MXene is that T groups (T = OH/ O/ F) are uniformly formed on the surface, which offers great potential for less interface voids.…”

Comparison of micro‐ and nano‐sized CuBTC particles on the CO2/CH4 separation performance of PEBA mixed matrix membranes

“…The peak of neat PEBA at 1094 cm −1 referred to the stretching vibration of the C‐O‐C group within the PEO segment. The PA segment also exhibited some relatively sharp peaks at around 3297, 1636 and 1730 cm −1 corresponding to ‐N‐H‐, H‐N‐C=O and O‐C=O groups (respectively) in the hard PA segment 25–53 . Despite the slight differences in membrane preparation methods, the spectra of the two series of membranes were consistent; indicating no reaction of CuBTC.ns with the solvent and no creation of new functional groups.…”

“…PEBA 1657, a polyether block amide composed of 40% polyamide (PA) and 60% polyethylene oxide (PEO), was selected as the polymer material. The impacts of different fillers including MOFs, [25][26][27][28][29][30] carbon nanotubes, 31,32 zeolites, [33][34][35] and other 2D and 3D inorganic materials [36][37][38] were investigated to enhance the CO 2 \CH 4 separation properties of PEBA. It is expected that the flexible structure of polymer chains displays sufficient compatibility with the particles to prohibit sieve-in-a-cage and rigidification defects at the polymer-particle interface.…”

MXene Materials for Designing Advanced Separation Membranes

“…In another promising demonstration, Liu et al employed MXenes as the filler of a poly(ether-block-amide) (PEBA) MMM for CO 2 capture. [73] Using Ti 3 C 2 T x nanosheets at a filler loading as low as 0.15 wt%, the researchers have prepared high-performance composite membranes on PAN supports by spin coating. Owing to the preferential affinity of (polar) CO 2 to (polar) Ti 3 C 2 T x particles and PEO blocks in PEBA used, the resulting MMM reached a remarkable CO 2 /N 2 selectivity of 72.5 with the CO 2 permeance of 21.6 GPU.…”

“…Importantly, the resulting membrane also showed good stability in a 120 h long continuous operation. [73] Again, using two PEBA varieties (and a water soluble polyurethane), Shamsabadi et al [114] also recently developed MMMs (and TFCs) for CO 2 capture. With Pebax 1657, which contains PEO blocks, they have shown MMMs (Figure 4g) with high selectivity and permeability, well exceeding the 2008 Robeson upper bound for CO 2 /N 2 (Figure 4h).…”