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Zinc-iodine redox flow batteries (ZIFBs) have emerged as promising energy storage systems due to their high-energy density. However, their practical use has been limited by their poor stability, low efficiency and high cost. In this work, we implemented a novel strategy to improve the performance and cyclability of ZIFBs, as well as decrease the chemical cost, by developing and utilizing ammonium-based electrolytes. An ammonium chloride supported zinc-iodine redox flow battery (AC-ZIFB) based on the ammonium iodide/triiodide redox couple was designed, and it achieved a high energy density of 137 Wh L -1 , Coulombic efficiency of ~99%, energy efficiency of ~80%, and a cycle-life of 2500 cycles at a 11-times lower chemical cost than conventional ZIFBs. Such improvements are mainly attributed to the multifunctional roles of cost-effective chemicals utilized in a new decoupled electrolyte design, which mitigates zinc dendrite formation, facilitates anodic and cathodic reaction kinetics and unlocks extra capacity with the primary aid of I 2 C l − formation. This straightforward, yet effective strategy, empowers the AC-ZIFB with excellent potential as a robust and practical redox flow battery and more broadly demonstrates a facile strategy of using multifunctional electrolyte chemistry to achieve a reliable, high-performance, and cost-competitive energy storage system.

Summary Polysulfide retention and catalysis are currently among the most important factors toward solving much of the technical challenges of lithium-sulfur (Li-S) batteries. Taking advantage of the electronic structure specific to tantalum, we explore the application of amorphous tantalum oxide with oxygen vacancies embedded inside a microporous carbon matrix as an electrocatalyst for the Li-S system. Through a pore-constriction mechanism, the dimensions of tantalum oxide are controlled to be nanosized with abundant polysulfide-retaining and catalytically active sites. High cycle and rate performances were achieved at practically relevant sulfur loadings and electrolyte content. We believe our identification of tantalum as a new catalyst material for Li-S batteries will incite more investigation into the specific selection of transition metals based on their electronic structures. Meanwhile, the “ship in a bottle” strategy will enlighten the structure design for energy conversion and storage systems.

The notorious shuttling behaviors and sluggish conversion kinetics of the intermediate lithium polysulfides (LPS) are hindering the practical application of lithium sulfur (Li-S) batteries. Herein, an ultrafine, amorphous, and oxygen-deficient niobium pentoxide nanocluster embedded in microporous carbon nanospheres (A-Nb2O5-x@MCS) was developed as a multifunctional sulfur immobilizer and promoter toward superior shuttle inhibition and conversion catalyzation of LPS. The A-Nb2O5-x nanocluster implanted framework uniformizes sulfur distribution, exposes vast active interfaces, and offers a reduced ion/electron transportation pathway for expedited redox reaction. Moreover, the low crystallinity feature of A-Nb2O5-x manipulates the LPS chemical affinity, while the defect chemistry enhances the intrinsic conductivity and catalytic activity for rapid electrochemical conversions. Attributed to these superiorities, A-Nb2O5-x@MCS delivers good Li-S battery performances, that is, high areal capacity of 6.62 mAh cm-2 under high sulfur loading and low electrolyte/sulfur ratio, superb rate capability, and cyclability over 1200 cycles with an ultralow capacity fading rate of 0.024% per cycle. This work provides a synergistic regulation on crystallinity and oxygen deficiency toward rapid and durable sulfur electrochemistry, holding a great promise in developing practically viable Li-S batteries and enlightening material engineering in related energy storage and conversion areas.

Lithium anode‐based batteries (LBs) are highly demanded in society owing to the high theoretical capacity and low reduction potential of metallic lithium. They are expected to see increasing deployment in performance critical areas including electric vehicles, grid storage, space, and sea vehicle operations. Unfortunately, competitive performance cannot be achieved when LBs operating under extreme temperature conditions where the lithium‐ion chemistry fail to perform optimally. In this review, a brief overview of the challenges in developing LBs for low temperature (60 °C) operation are provided followed by electrolyte design strategies involving Li salt modification, solvation structure optimization, additive introduction, and solid‐state electrolyte utilization for LBs are introduced. Specifically, the prospects of using lithium metal batteries (LMBs), lithium sulfur (Li‐S) batteries, and lithium oxygen (Li‐O2) batteries for performance under low and high temperature applications are evaluated. These three chemistries are presented as prototypical examples of how the conventional low temperature charge transfer resistances and high temperature side reactions can be overcome. This review also points out the research direction of extreme temperature electrolyte design toward practical applications., This review introduces current progress of electrolyte design in lithium metal batteries to realize improved performance under extremely low and high temperature applications. By reviewing the scientific issues related to the current electrolyte design strategy, including Li salt modification, solvent component optimization, electrolyte additive introduction and solid‐state electrolyte utilization, this review points out the research direction toward practical applications.

A BN membrane with a distinct nanoconfinement effect toward efficient ethylene/ethane separation is presented. The horizontal and inclined self-assembly of 2D BN nanosheets endow the BN membrane with abundant percolating nanochannels, and these nanochannels are further decorated by reactive ionic liquids (RILs) to tailor their sizes as well as to achieve nanoconfinement effect. The noncovalent interactions between RIL and BN nanosheets favor the ordered alignment of the cations and anions of RIL within BN nanochannels, which contributes to a fast and selective ethylene transport. The resultant membranes exhibit an unprecedented separation performance with superhigh C2 H4 permeance of 138 GPU and C2 H4 /C2 H6 selectivity of 128 as well as remarkably improved long-term stability for 180 h, outperforming reported state-of-the-art membranes.

Electrochemical water splitting, which is economical and sustainable, has been considered as one of the most potential methods to produce large amounts of hydrogen with high purity. However, the de...

The escalating level of atmospheric CO2 is one of the most pressing environmental concerns of our age. The development of advanced materials for efficient CO2 capture and separation is a burgeoning field that has spurred great interest in materials science. Among the contenders in the arena of CO2 adsorption materials, porous carbons have emerged as particularly promising candidates owing to their unique properties suitable for CO2 capture under a wide range of conditions. This review systematically presents the primary design and synthesis strategies of porous carbons and seminal research that has inspired their advancements, with specific emphasis on uncovering their structure–performance relationship in CO2 capture. Moreover, the underlying mechanism of CO2 adsorption over porous carbons with a defined pore texture and surface chemistry is particularly discussed. Finally, the current challenges and future opportunities in developing porous carbons for practical CO2 capture are summarized. This review is intended to serve as a guideline for rational design of tailored porous carbon materials toward high-performance CO2 capture, benefiting both scientists and engineers active in this emerging and potentially world-changing discipline.

A series of functional block copolymers (COPs) was synthesized through the ring-opening polymerization of e-caprolactone (CL) and γ-(carbamic acid benzyl ester)-e-caprolactone (CABCL) monomers at different ratios, and then the effects of the COP additives on the hydrolytic and oxidative degradation and mechanical properties of PCL/COP samples were studied. From characterization using DSC, POM, AFM, WAXD, SAXS, etc., it was demonstrated that the content and distribution of pendant side chains in the COPs can alter the nucleation of macromolecular chains, and then modulate the lamellar thickness and crystallinity of the PCL/COP samples. Such variations of the macromolecular structures result in distinct changes in the mechanical properties during degradation. These results provide useful guidance for the development of ideal materials for biodegradable polymer stents with tunable degradation rates and the desirable evolution of the mechanical properties.

For ethylene/ethane separation, fabrication of facilitated transport membranes (FTMs) with properties of high ethylene permeability, selectivity, long-term stability and economic feasibility remains a great challenge. In this study, a series of deep eutectic solvents (DESs) containing NO3- as anion were designed, synthesized and characterized for the first time. Then, novel DES-FTMs were fabricated successfully through the incorporation of the transport carrier (AgNO3) into as-synthesized DESs. The investigation of structure-performance relationships of FTMs suggested that the hydrogen bond acceptors (HBAs), hydrogen bond donors (HBDs) and their molar ratios greatly manipulated separation performance of FTM, which was also greatly affected by the carrier concentration. The right combinations of HBAs, HBDs and carrier concentration could significantly enhance the ethylene/ethane selectivity up to 125. The operating conditions of the separation process were optimized, confirming ethylene/ethane selectivity increased with the decrease of the transmembrane pressure and operating temperature. The synergetic regulation of hydrogen bond and coordination interactions between DES and carrier could tune the interactions between the silver cation and its counter anion, which efficiently promoted the disassociation of carrier and increased carrier activity, leading to high ethylene permeability and ethylene/ethane selectivity. The Bronsted acidic property of HBAs endowed the FTMs with good stability. The low cost and facile availability of the DESs and carrier rendered FTMs with good economic feasibility. This study may reveal the definite potentiality of DES-FTMs in ethylene/ethane separation.

Mn and N codoped carbon materials are proposed as one of the most promising catalysts for the oxygen reduction reaction (ORR) but still confront a lot of challenges to replace Pt. Herein, a novel gas-phase migration strategy is developed for the scale synthesis of atomically dispersed Mn and N codoped carbon materials (g-SA-Mn) as highly effective ORR catalysts. Porous zeolitic imidazolate frameworks serve as the appropriate support for the trapping and anchoring of Mn-containing gaseous species and the synchronous high-temperature pyrolysis process results in the generation of atomically dispersed Mn-N

Microporous framework membranes such as metal-organic framework (MOF) membranes and covalent organic framework (COF) membranes are constructed by the controlled growth of small building blocks with large porosity and permanent well-defined micropore structures, which can overcome the ubiquitous tradeoff between membrane permeability and selectivity; they hold great promise for the enormous challenging separations in energy and environment fields. Therefore, microporous framework membranes are endowed with great expectations as next-generation membranes, and have evolved into a booming research field. Numerous novel membrane materials, versatile manipulation strategies of membrane structures, and fascinating applications have erupted in the last five years. First, this review summarizes and categorizes the microporous framework membranes with pore sizes lower than 2 nm based on their chemistry: inorganic microporous framework membranes, organic-inorganic microporous framework membranes, and organic microporous framework membranes, where the chemistry, fabrications, and differences among these membranes have been highlighted. Special attention is paid to the membrane structures and their corresponding modifications, including pore architecture, intercrystalline grain boundary, as well as their diverse control strategies. Then, the separation mechanisms of membranes are covered, such as diffusion-selectivity separation, adsorption-selectivity separation, and synergetic adsorption-diffusion-selectivity separation. Meanwhile, intricate membrane design to realize synergistic separation and some emerging mechanisms are highlighted. Finally, the applications of microporous framework membranes for precise gas separation, liquid molecule separation, and ion sieving are summarized. The remaining challenges and future perspectives in this field are discussed. This timely review may provide genuine guidance on the manipulation of membrane structures and inspire creative designs of novel membranes, promoting the sustainable development and steadily increasing prosperity of this field.

All-solid-state lithium ion batteries (ASSLBs) are considered next-generation devices for energy storage due to their advantages in safety and potentially high energy density. As the key component in ASSLBs, solid-state electrolytes (SSEs) with non-flammability and good adaptability to lithium metal anodes have attracted extensive attention in recent years. Among the current SSEs, composite solid-state electrolytes (CSSEs) with multiple phases have greater flexibility to customize and combine the advantages of single-phase electrolytes, which have been widely investigated recently and regarded as promising candidates for commercial ASSLBs. Based on existing investigations, herein, we present a comprehensive overview of the recent developments in CSSEs. Initially, we introduce the historical development from solid-state ionic conductors to CSSEs, and then summarize the fundamentals including mechanisms of lithium ion transport, key evaluation parameters, design principles, and key materials. Four main types of advanced structures for CSSEs are classified and highlighted according to the recent progress. Moreover, advanced characterization and computational simulation techniques including machine learning are reviewed for the first time, and the main challenges and perspectives of CSSEs are also provided for their future development.

Efficient olefin/paraffin separation is a grand challenge because of their similar molecular sizes and physical properties, and is also a priority in the modern chemical industry. Membrane separation technology has been demonstrated as a promising technology owing to its low energy consumption, mild operation conditions, tunability of membrane materials, as well as the integration of physical and chemical mechanisms. In this work, inspired by the physical mechanism of mass transport in channel proteins and the chemical mechanism of mass transport in carrier proteins, recent progress in channel‐based and carrier‐based membranes toward olefin/paraffin separations is summarized. Further, channel‐based membranes are categorized into membranes with network structures and with framework structures according to the morphology of channels. The separation mechanisms, separation performance, and membrane stability in channel‐based and carrier‐based membranes are elaborated. Future perspectives toward membrane‐based olefin/paraffin separation are proposed., Recent progress in channel‐based and carrier‐based membranes toward olefin/paraffin separations is summarized. Further, channel‐based membranes are categorized into membranes with network structures and with framework structures according to the morphology of channels. The separation mechanisms, separation performance, and membrane stability in channel‐based and carrier‐based membranes are elaborated. Future perspectives toward membrane‐based olefin/paraffin separation are proposed.

Herein, high performance polyethersulfone (PES) membranes were fabricated by introducing a series of imidazole-based deep eutectic solvents (DESs) as functional additives, which could tailor membrane structure due to the synergetic effect between DES components in phase inversion process. The addition of those DESs to the casting solutions all improved membrane porous structure, which contributed to a remarkably enhanced permeability and a high selectivity of the resultant membranes. Especially, the PES membrane with tetrabutylammonium chloride/imidazole as additive had a maximum water flux of 781 L/(m2 h), which was about 6.45 times that of the additive-free membrane, and a high BSA rejection of 97.7% at 2 bar. Moreover, the antifouling performance as well as thermal and mechanical properties of the prepared membranes was investigated. Overall, this work indicates the promise of imidazole-based DESs as alternative pore-forming additives for the fabrication of ultrafiltration membranes with superior performance.

In this work, a superhydrophilic Ti foam was designed and fabricated by applying a novel one-step hydrothermal approach to achieve highly efficient oil in water emulsion separation. Attributed to the synergistic effect of the surface roughness constructed by hierarchical flower-like TiO2 nanostructures and the surface hydrophilicity induced by titanium oxy-fluoride groups, the as-prepared Ti foam exhibited superhydrophilicity and underwater superoleophobicity. The formation of flower-like TiO2 nanostructures was studied and a possible “partial replacement” fluorinated process was proposed. Oil in water emulsion separation test showed that the superhydrophilic Ti foam could handle with various emulsions only under gravity with high separation efficiency over 99%. The separation efficiency remained high even after 20 times of reusing, demonstrating good reusability. More importantly, the superhydrophilic Ti foam could still maintain its wettability after immersed corrosive solutions for 48 h or stored under ambient atmosphere for three months, indicating excellent anti-corrosion property and long-term storage stability. We envision the methodology for the construction of a superhydrophilic surface by a simple and low-cost hydrothermal process will shed light on the Ti-based material design and also pave the way for applications in other fields such as liquid manipulation, fluidic devices and bioadhesion control.

In this work, a novel strategy was reported for improving SO2 capture through multiple-site interactions of N-imidazole derivative. The tris (2-(1-H-imidazole-1-y1)ethyl) amine (TIA) was designed, synthesised and mixed with water to form the mixed absorbents for SO2 absorption. The physical properties were determined and the mixed absorbents exhibited low densities and viscosities, which are beneficial to the mass and heat transfer. The SO2 absorption reached equilibrium rapidly within 60 s and as high as 2.09 mol SO2 per mol TIA could be absorbed at low SO2 concentration (

Deep eutectic solvents (DESs) have been seen as promising absorbents for SO2 capture in recent years. In this work, a series of DESs based on imidazole derivatives were synthesized to investigate the low pressure SO2 absorption. The physical properties were determined, and the DESs exhibited low viscosities and high stability. Effects of composition, operating temperature and pressure, and water content on SO2 absorption capacity were investigated. It was demonstrated that the 1-butyl-3-methylimidazolium chloride (BmimCl):4-methylimidazole (4CH3-Im) (1:2) could absorb 1.42 and 0.189 gSO2/gDES at 101.3 and 1 kPa SO2 partial pressure, respectively, which were higher than most reports to date under this condition. The absorbed SO2 could be released easily under mild condition, and there was no change in absorption performance after 5 cycles. Furthermore, the absorption mechanism studied by FTIR and NMR indicated that the high SO2 absorption capacity originated from the synergistic interaction of BmimCl and 4...

Facilitated transport membranes (FTMs) for olefin/paraffin separations have failed to achieve commercial success due to the instability of carriers although great efforts have been made. In this work, ultra-stable and cost-efficient protic ionic liquid based FTMs (PIL-FTMs) were firstly prepared by utilizing the Bronsted acidic property of PILs to stabilize the carrier. The gas solubility in the carrier/PILs was measured and the separation performances of PIL-FTMs were evaluated systemically. The results indicated that the structure of PILs affected the C2H4 permeability and the presence of ether group and hydroxyl group in PILs significantly enhanced the C2H4/C2H6 selectivity. The carrier concentration led to structural variation of PIL-FTMs, thus manipulating the gas separation performances of PIL-FTMs. The increase of transmembrane pressure decreased C2H4 permeability and C2H4/C2H6 selectivity, indicating a typical feature of FTMs. The increase of temperature increased the C2H4 permeability but decreased C2H4/C2H6 selectivity. The separation performances of PIL-FTMs were much higher than other results in the literature. Furthermore, the PIL-FTMs exhibited excellent stability during the long-term experiments carried out for six months. Finally, the investigation of separation mechanism revealed that the hydrogen-bonding and coordinative interactions between PILs and carrier accounted for the high separation efficiency of PIL-FTMs. In all, the excellent long-term stability, outstanding separation performances and economic feasibility of PIL-FTMs could play an important role in moving these membranes toward industrial application.

With the aim of removing and recycling oil and organic solvent from water, a facile and low-cost crosslinking polymerization method was first applied on surface modification of cotton fabrics for water/oil separation. Micro-nano hierarchical rough structure was constructed by triethylenetetramine (TETA) and trimesoyl chloride (TMC) that formed a polymeric layer on the surface of the fabric and anchored Al2O3 nanoparticles firmly between the fabric surface and the polymer layer. Superhydrophobic property was further obtained through self-assembly grafting of hydrophobic groups on the rough surface. The as-prepared cotton fabric exhibited superoleophilicity in atmosphere and superhydrophobicity both in atmosphere and under oil with the water contact angle of 153° and 152° respectively. Water/oil separation test showed that the as-prepared cotton fabric can handle with various oil-water mixtures with a high separation efficiency over 99%. More importantly, the separation efficiency remained above 98% over 20 cycles of reusing without losing its superhydrophobicity which demonstrated excellent reusability in oil/water separation process. Moreover, the as-prepared cotton fabric possessed good contamination resistance ability and self-cleaning property. Simulation washing process test showed the superhydrophobic cotton fabric maintained high value of water contact angle above 150° after 100 times washing, indicating great stability and durability. In summary, this work provides a brand-new way to surface modification of cotton fabric and makes it a promising candidate material for oil/water separation.

Protic ionic liquids (PILs) were utilized for the fabrication of composite membranes containing silver salt as the C2H4 transport carrier to perform C2H4/C2H6 separation for the first time. The intrinsic nanostructures of PILs were adopted to construct fast and selective C2H4 transport nanochannels. The investigation of structure–performance relationships of composite membranes suggested that transport nanochannels (polar domains of PILs) could be tuned by the sizes of cations, which greatly manipulated activity of the carrier and determined the separation performances of membranes. The role of different carriers in the facilitated transport was studied, which revealed that the PILs were good solvents for dissolution and activation of the carrier due to their hydrogen bond networks and waterlike properties. The operating conditions of separation process were investigated systemically and optimized, confirming C2H4/C2H6 selectivity was enhanced with the increase of silver salt concentration, the flow rate ...

Binary metal chloride deep eutectic solvents (DESs) were first prepared by adding different metal chlorides into 1-butyl-3-methylimidazolium chloride ([BMIM]Cl)/CuCl DESs to improve the activity of the Cu+ carrier for ethylene/ethane separation. The binary metal chloride DESs were impregnated in the polyvinylidene fluoride microporous membrane to prepare the supported liquid membranes (SLMs). The performance of the SLMs based on binary metal chloride DESs was evaluated by ethylene/ethane separation experiments. For the SLM based on 0.5[BMIM]Cl-CuCl-1/15ZnCl2 DES, the selectivity of ethylene/ethane mixture increased from 10.7 to 17.8, and the ethylene permeability decreased slightly from 28.6 barrer to 25.8 barrer, compared to 0.5[BMIM][Cl] SLM without ZnCl2. Furthermore, it exhibited long-term stability for more than 150 h. The beneficial role of ZnCl2 for Cu+ carrier was analyzed by electrospray ionization mass spectrometry, Raman spectroscopy, and quantum mechanical calculation. The Raman spectrum showe...

In the petrochemical industry, it is critical to separate the light olefins/paraffins mixtures via an efficient and economic method. In this work, a series of deep eutectic solvents (DESs) (choline chloride (ChCl)-glycerol (G), ChCl-ethylene glycol (EG), 1-butyl-3-methylimidazolium chloride ([Bmim][Cl])-G, and [Bmim][Cl]-EG) dissolving CuCl were used as novel membrane liquids to fabricate supported liquid membranes (SLMs) for the C2H4/C2H6 mixture separation. Interactions based on a hydrogen bond network in different DESs were characterized by time-of-flight mass spectroscopy (TOF-MS), nuclear magnetic resonance (1H NMR), and Fourier transform infrared (FT-IR) spectroscopy. Moreover, by absorption experiments, the Cu+ activity was quantitatively described based on a first-order equilibrium model. The effects of DESs species, CuCl concentration, transmembrane pressure, temperature, and time on separation performances were investigated by C2H4/C2H6 mixture permeation experiments. CuCl/ChCl-EG-based SLMs pos...

Deep eutectic solvents (DESs), as a new generation of designer solvents, were firstly employed to fabricate the supported liquid membranes (SLMs) for the olefin/paraffin separation via facilitated transport. The novel CuCl/DESs-SLMs were prepared by impregnating the mixture of choline chloride-glycerol based DESs and copper (I) chloride (CuCl) into the microporous nylon membranes. The results of FTIR, 1 HNMR and mass spectrometry (MS) confirmed the existence of various Cu (I)-containing anionic species and hydrogen-bond networks in the membrane liquid of CuCl/DESs. The CuCl/DESs-SLMs were characterized by scanning electron microscope (SEM), contact angle measurement and weight analysis, and their performances of CuCl/DESs-SLMs were evaluated by the C 2 H 4 /C 2 H 6 separation experiments. The effects of DESs composition, CuCl concentration, operation pressure and temperature were investigated systemically. It was found that the activity and chemical stability of Cu (I)-containing anionic species were enhanced through the hydrogen-bond interactions between the anionic species and DESs, which significantly increased the permeability of C 2 H 4 and selectivity of C 2 H 4 /C 2 H 6 . Compared with other studies, the CuCl/DESs-SLMs exhibited comparable permeability and higher selectivity up to 20 for C 2 H 4 /C 2 H 6 . In conclusion, the CuCl/DESs-SLMs provided a promising method for the C 2 H 4 /C 2 H 6 separation.

Supported liquid membranes (SLMs) have exhibited great potential as interesting materials for the separation of olefin/paraffin mixtures. To further improve the performance of SLMs, novel and sustainable silver-based deep eutectic solvents (DESs) constructed from trifluoromethanesulfonate (AgCF3SO3) and acetamide (CH3CONH2) were synthesized as membrane liquids for the first time. Their formation mechanism and structure were investigated intensively, confirming that multiple coordination and hydrogen-bonding interactions yielded homogeneous and stable liquids that contained free silver ions and silver-containing cationic complexes as carriers for the facilitated transport of C2H4. The as-prepared DES-SLMs were characterized by SEM and ATR-FTIR and their separation performances were investigated by C2H4/C2H6 separation experiments. The effects of the composition of the silver-based DESs, the operating temperature, and the transmembrane pressure were also investigated systemically. The permeability selectivi...

For the separation of an ethylene/ethane mixture, a novel copper(I)-based supported ionic liquid membrane (SILM) with high permeability has been fabricated. This SILM was prepared from a polyvinylidene fluoride microporous membrane impregnating the copper(I) based IL which formed by the cuprous chloride (CuCl) and 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]). Scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy, and time of flight mass spectroscopy were used to characterize the SILM. Pure and mixed gas permeation experiments were carried out to investigate the influences of ILs composition, trans-membrane pressure, temperature, and time upon the separation performance. This SILM showed comparable C2H4 permselectivity but outstanding permeability with a long-term stability beyond the reported polymeric membrane upper bound. At the CuCl/[Bmim][Cl] ratio of 2, the C2H4 permeability and permselectivity reached 2653 barrer and 11.8, respectively. Furthermore, t...

Poly (L-lactic acid) (PLLA) membranes were fabricated through immersion precipitation method. 1, 4-dioxane (DX), N-methyl-2-pyrrolidone (NMP), N, N-dimethylformamide (DMF), N, N-dimethyl-acetamide (DMAc), and DX/NMP, DX/DMF and DX/DMAc were used as solvents severally. With a focus on the PLLA/DX/NMP/H2O system, the effect of solvent mixture on PLLA membrane was investigated by altering the ratio of DX/NMP. Various membrane morphologies were obtained, which were further correlated by mean of solubility parameter and viscosity of casting solution. It was found that the membrane cast with DX/NMP (1/1) exhibited ideal structure and better performance compared with membranes cast with same concentration of PLLA.

Membrane technology is a forward-looking approach for gas separation, while the implementation of membrane with high performance for ethylene/ethane separation still challenges the world. Herein, a multifunctional ternary deep eutectic solvent (DES)-based membrane was constructed for the cost-effective ethylene/ethane separation. The incorporation of a sweetener (Al(NO3)3) with the AgNO3/methylacetamide (NMA) mixture to form a ternary DES not only significantly promoted the ethylene/ethane selectivity but also enhanced the long-term stability of resultant membranes, which killed two birds with one stone. Various spectroscopic characterization and quantum mechanical calculations revealed that the complexing interaction between Ag+ and NMA and the complexing interaction between Al3+ and NO3− weakened the electrostatic interaction between Ag+ and NO3−, and improved the interaction energy between ethylene molecule and Ag+ carrier. By the synergy effects of two different complexing interactions, the ternary DES-based membranes exhibited high ethylene permeability, ethylene/ethane selectivity and stability, outperforming majority of the previously published data. Therefore, the membranes proved the grand potential for ethylene/ethane separation, and this work will shed light on the design of multifunctional liquid membranes for precise molecular separation.

Poly(l-lactic acid) (PLLA) composite membranes were fabricated by nonsolvent induced phase separation method using polyaniline (PANI) as an additive. Membrane structure was characterized by attenuated total reflectance Fourier transform-infrared spectroscopy, X-ray diffraction, scanning electron microscopy, porosity, and pore size analysis. Membrane performance was assessed by goniometer, pure water flux, molecular weight cut-off, static adsorption and dynamic filtration. The incorporation of PANI significantly improved the hydrophilicity and permeability of PLLA composite membrane, and eventually enhanced the antifouling performance of composite membrane compared with pure PLLA membrane. It was demonstrated that PLLA composite membrane with 1 wt % PANI had better separation and antifouling performance compared with other composite membranes. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44452.