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Two-dimensional (2D) nanosheets can be desirable materials to fabricate membranes for ionic and molecular separation such as water purification, seawater desalination, solvent separation, and gas separation. Molybdenum disulfide (MoS 2) can be a desirable candidate among the family of 2D nanosheets due to their exceptional physical properties, high stability, and well-defined scalable synthesis methods. In this work, a highly aligned MoS 2 layer is fabricated on a centimeter-scale by coating electrochemically exfoliated MoS 2 nanosheets via a continuous slot-die coating method. Particular, an additive to stabilize the resulting dispersion of exfoliated MoS 2 nanosheets further enlarges the capillary width of the stacked MoS 2 nanosheets, which enables the efficient H 2 permeation properties as 5.57 × 10−6 mol m−2 s−1 Pa−1 and 13 of H 2 /CO 2 ideal selectivity. Furthermore, this MoS 2 -based membrane exhibits high thermal stability. While the temperature varies, it shows stable and selective gas permeation properties over 10−6 mol m−2 s−1 Pa−1 H 2 permeance, while H 2 /CO 2 ideal selectivity remained at 150 °C for 7 days. [Display omitted] • Scalable synthesis of MoS 2 nanosheet is achieved via electrochemical exfoliation for membrane fabrication. • Large-area assembly of MoS 2 nanosheets is demonstrated on polymer support via continuous slot die coating. • H 2 permeation is enhanced by enlarged interlayer spacing in the presence of adsorbed additives. • Ultrafast and H 2 -selective permeation is confirmed even at high temperatures up to 150 °C. [ABSTRACT FROM AUTHOR]

• Recent developments in Metal–organic framework-based mixed matrix membranes for hydrogen separation were summarized. • An in-depth discussion on fabrication and modification strategies for H 2 /N 2 , H 2 /CH 4 , and H 2 /CO 2 separation was presented. • Advanced characterization techniques for studying the MOF-polymer interface. • The separation performance under harsh conditions and improvements in robustness and durability were emphasized. • The outlook and future directions for MOF-based MMMs were proposed. Membrane separation is one of the low-energy hydrogen purification technologies that effectively mitigates the carbon footprint and is eco-friendly process for large-scale integration. Conventional membranes, such as polymeric ones, typically suffer from the trade-off between permeability and selectivity demonstrated by the Robeson's upper bound. Metal organic frameworks (MOFs) are recognized as promising fillers to fabricate the mixed matrix membranes (MMMs) for hydrogen separation due to their high porosity, large internal surface area, and structural tunability. Herein, this review offers a comprehensive summary of the related literature that explores the challenges in developing MMMs, and presents an in-depth discussion on fabrication and modification strategies of MOF-based MMMs specifically for H 2 /N 2 , H 2 /CH 4 , and H 2 /CO 2 separation. Advanced characterization techniques for understanding membrane properties, specifically the MOF–polymer interface, are outlined. Subsequently, the hydrogen separation performance of MOF-based MMMs under harsh operating conditions and improvement in robustness and long-term durability properties are emphasized. The outlook and future directions for MOF-based MMMs are also proposed. It is anticipated that this review will serve as a stepping stone for the coming MOF-based MMMs research on sustainable and large-scale application for hydrogen separation. [ABSTRACT FROM AUTHOR]

• An in-depth review of the Pd-based membranes to reach high-performance membranes. • Ceramics are the best materials for use as a support and surface modification. • The ELP is a top choice for producing high-H 2 permeance membranes. • Pd-Ag membranes provide cost-effective high H 2 permeance. Today, the world faces two critical challenges: air pollution and the depletion of fossil fuel supplies. In this condition, hydrogen is an energy carrier with zero pollution and high energy utilization. Thus, the production and purification of hydrogen have been appreciated. The Pd-based membrane separation technology has attracted more attention in the continuous separation and purification of hydrogen in the last decade. Pd-based membranes have significant permeability and exclusive perm-selectivity toward hydrogen. To actual industrialization, Pd membranes must meet numerous performance targets, including rendering high H 2 permeance, resistance to hydrogen embrittlement, high chemical/thermal/mechanical stability, and low cost. Studies have shown that various parameters such as alloying, fabrication of supported membranes, performing surface modification on the support, and type of fabrication method can be effective in achieving these targets. This review has covered recent developments concentrating on the most influential parameters to fabricate membranes with high performance for actual industrialization. It can be concluded that by applying Pd alloys using the ELP technique, can be possible to achieve a cost-effective membrane with high hydrogen permeance and hydrogen perm-selectivity on a large scale. In addition, ceramics are the best materials for support and surface modification. [ABSTRACT FROM AUTHOR]