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[Display omitted] • Flexible and defects-free MMMs possess bi-continuous MOFs pathway. • DA promotes heterogeneous nucleation and growth of ZIF-8 on fiber. • In-situ polymerization intensifies interface affinity between ZIF-8 and PEO. • CO 2 permeability and CO 2 /N 2 selectivity surpass 2019 McKeown upper bound. Highly-loaded metal–organic frameworks (MOFs) based mixed matrix membranes (MMMs) are essential for high-efficiency gas separation. However, the continuous distribution of MOFs across the membrane with intensified interface remains challenging. Herein, a flexible and defects-free MMM with a bi-continuous MOFs pathway is constructed by dopamine (DA)-assisted MOFs growth along nanofibers. Nanofibers are used to upload and distribute ZIF-8, which continues to grow via an epitaxial growth strategy to obtain ZIF-8 fibers, achieving ZIF-8 continuous both in long and short range. DA promotes heterogeneous nucleation and growth of ZIF-8 on fiber surface by chelating with Zn2+ through –OH and –NH 2 groups. DA also ensures excellent interfacial compatibility by hydrogen bonding interaction between amino groups of DA and ether-oxygen groups of PEO. Finally, the highly-loaded MMM is constructed by in-situ photopolymerization of Poly (ethylene glycol) diacrylate) to embrace ZIF-8 fibers tightly. The resultant MMM presents ZIF-8 loading as high as 72.41 vol% with Young's modulus of 33.42 MPa, and unchanged morphology and separation performances after bending for 180° over 50 times, revealing outstanding mechanical properties. The CO 2 permeability and CO 2 /N 2 selectivity are 280.3 % and 73.0 % higher than the PEO membrane, surpassing the 2019 McKeown upper bound. [ABSTRACT FROM AUTHOR]

• In-situ position of ILs into cages of ZIF-8 was proposed to tune cage size. • CO 2 -philic cages constructed by ILs improve CO 2 adsorption. • Molecular simulation reveals increased CO 2 adsorption by increasing ILs in cages. • CO 2 /N 2 selectivity of MMMs is increased due to pore screening and CO 2 adsorption. The regulation on cage size and CO 2 -philic environment of metal–organic frameworks (MOFs) is essential to improve CO 2 capture. In this work, [Bmim][Tf 2 N] was proposed to position into cages of ZIF-8 to achieve the selective permeation of CO 2 by pore screening and CO 2 adsorption. [Bmim][Tf 2 N] was introduced into cages of ZIF-8 by "adsorption-infiltration" strategy. Due to the strong interaction between [Tf 2 N]− and ZIF-8, the cages present a CO 2 -philic environment, which preferentially attracts CO 2 to enter these cages, ensuring the dissolution selectivity of CO 2. Besides, the proper cage size tuned by [Bmim][Tf 2 N] provides CO 2 with a faster transport channel due to its smaller average kinetic diameter than N 2 , guaranteeing the diffusion selectivity of CO 2. Consequently, the CO 2 separation in [Bmim][Tf 2 N]@ZIF-8/Pebax MMMs is intensified. With increasing the [Bmim][Tf 2 N] content in cages of ZIF-8, the pore volume by BET results decreases and the CO 2 adsorption from molecular simulation increases. In response, the CO 2 /N 2 selectivity of [Bmim][Tf 2 N]@ZIF-8/Pebax MMMs is enhanced constantly. Meanwhile, the CO 2 permeability is declined due to the narrowed cage size. All of these results demonstrate the significance of pore screening and CO 2 adsorption induced by [Bmim][Tf 2 N]. Specifically, [Bmim][Tf 2 N] 8 @ZIF-8/Pebax MMM at filler loading of 15 wt% exhibits the CO 2 permeability of 108.3 Barrer and the CO 2 /N 2 selectivity of 86.7, exceeding the 2008 Robeson upper bound. Especially the CO 2 /N 2 selectivity locates at a higher level than those of most reported works, indicating that appropriate tuning of the physicochemical properties within the nanocages of MOFs is significative to improve CO 2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] • PSA modified hollow NH 2 -ZIF-8 (PHNZ) with high amino content was designed. • PSA hard template strategy was used to synthesis NH 2 -ZIF-8 rapidly. • The vesicle shape of PHNZ constructs low-resistance region to improve CO 2 permeability. • CO 2 /N 2 selectivity is improved by PSA layer and CO 2 affinity of amino groups. The amino functionalization of MOFs has been verified to be effective in improving the selective permeation of CO 2. However, the introduction of amino groups into ZIF-8 by mixed ligands strategy is hard to achieve due to the high steric hindrance of benzene ring in 2-aminobenzimidazole ligand, resulting in insufficient content of amino groups. Therefore, in this work, polystyrene-acrylate (PSA) template is proposed to provide abundant adsorption and reaction sites for the rapid synthesis of NH 2 -ZIF-8 with high content of 2-aminobenzimidazole. Furthermore, the incomplete etching strategy is used to construct PSA modified hollow NH 2 -ZIF-8 nanospheres (PHNZ). Importantly, the thickness of PSA layer and the hollow size are adjusted by the etching time, as revealed by the SEM and TEM images. In this PHNZ, the modified PSA can provide good interface compatibility between PHNZ and Pebax matrix to enhance the CO 2 selectivity, while the hollow structure can reduce the mass transfer resistance and improve the gas permeability. Moreover, the introduced amino groups can enhance the CO 2 affinity of PHNZ and further improve the CO 2 /N 2 selectivity of the PHNZ-based mixed matrix membranes (MMMs). Benefiting from the synergy of good interface compatibility and enhanced CO 2 affinity from the amino groups, the PHNZ/Pebax MMMs present greatly improved CO 2 /N 2 selectivity in contrast with pure Pebax and NH 2 -ZIF-8 based membranes. Besides, as the etching time increases, the PHNZ-2 and PHNZ-3 based MMMs present a higher CO 2 permeability than that of NH 2 -ZIF-8 based MMM, revealing the significance of the hollow structure. The PHNZ-2/Pebax MMM with filler loading of 10 wt% expresses the best gas separation performance with the CO 2 permeability of 121.9 Barrer and CO 2 /N 2 selectivity of 96.6, respectively, showing an increase of 54.7 % and 98.0 % in contrast with pure Pebax membrane. Meanwhile, this CO 2 separation performance is far beyond the Robeson upper bound in 2008 and close to the McKeown upper bound in 2019, demonstrating that the proposed PHNZ displays a promising and competitive potential in MMM based CO 2 capture. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) based mixed matrix membrane (MMM) for CO 2 capture shows insufficient CO 2 permeability due to random disperse of MOFs in form of individual particle. Therefore, in this work, a continuous MOFs transport pathway for CO 2 with low resistance was constructed in the MMM by assistance of electrospun nanofiber. Specifically, PAN electrospun nanofiber mat (NFM) was utilized as skeleton to obtain continuous ZIF-8 nanofibers. Then flexible polyethylene glycol (PEG) molecules were photo-polymerized in situ into the inner-voids within ZIF-8@PAN NFM to form dense membrane. As a result, ZIF-8 particles are distributed in PEO matrix continuously, leading to a low-resistance transport pathway for gas molecules in MMM, which is proved by the cross-sectional SEM images. Furthermore, the higher Tg of ZIF-8@PAN-x/PEO MMM by DSC also indicates the good interfacial compatibility between ZIF-8 and PEO. Compared with pure PEO membrane, all the ZIF-8@PAN-x/PEO MMMs present both enhanced CO 2 permeability and CO 2 /N 2 selectivity. The enhanced CO 2 permeability is attributed to the continuous ZIF-8 transport pathway, and the improved selectivity is ascribed to the size screening from nanofibers overlapping and stacking and the tortuous transport pathway. Importantly, compared with ZIF-8/PEO MMM, in which ZIF-8 particles are randomly dispersed into PEO matrix, the ZIF-8@PAN-4/PEO MMM with the same ZIF-8 loading of about 16.6 wt% presents enhanced CO 2 permeability and CO 2 /N 2 selectivity, which are increased by 52.4% and 44.3%, respectively. This is due to the continuous ZIF-8 transport pathway and good interfacial compatibility, which is also confirmed by the result of gas diffusivity and solubility coefficients. Together with the outstanding mechanical strength and stability, the proposed MMM with continuous ZIF-8 transport pathway paves a new way to improve CO 2 permeability. [Display omitted] • MMM with continuous MOFs pathway was constructed to capture CO 2. • PAN nanofibers were used to induce MOFs continuous in long-range. • MMM was obtained by in-situ polymerization of PEG within MOFs NFM. • Both high permeability and selectivity were achieved by continuous gas pathway. [ABSTRACT FROM AUTHOR]

The Carnian Pluvial Episode (CPE) was a dramatic climatic event during the early Late Triassic. The CPE has been recognized worldwide and is marked by the termination of carbonate platform successions and by pronounced negative δ13C excursions (denoted as the CPE excursion). The onset of the CPE has been proposed to be linked with the volatile eruption of the Wrangellia Large Igneous Province (W-LIP). However, this extreme climatic event remains disputed in terms of its precise global correlation, timing of onset, duration, and global magnitude. We compiled a database of 13 conodont biozone-controlled stable-isotope reference sections throughout the Tethyan region. After a reexamination of previously published conodont taxonomy from each section, the statistics on the conodont assemblages/zones yield a global set of 17 high-resolution conodont Unitary Association Zones (UAZs) spanning the entire Carnian successions. A set of age-tie points placed an age model on this global UAZ scale. We added paired δ13C carb and δ13C org data from two sections in South China to other records in this global database, and then normalized all carbon-isotope datasets. A pronounced negative δ13C carb excursion with a magnitude of −2± 0.5‰ (from an average of ~3‰ to ~1‰) is evident in these normalized trends and is recognized around the entire Tethys realm. The CPE excursion coincides with conodont UAZ-4 (~234 Ma) through UAZ-8 (within the Mazzaella carnica and Paragondolella praelindae zones, Julian2) and has a duration of ca. 1.5 Myr. We note that an apparent delayed onset of the CPE excursion in South China relative to elsewhere in the Tethys as suggested by previous studies may have been an artifact caused by incomplete conodont-stratigraphic records and/or irregularities in taxonomic identification. A carbon and phosphorus cycle model highlight the strong relationship between the eruption of the W-LIP and CPE excursion; however, the estimated amount of CO 2 volatiles released by the W-LIP would directly account for only ~25% of the total amount of light‑carbon required to explain the combined magnitude and duration of the global CPE excursion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow ZIF-8 in micron accumulated continuously across membrane to construct transport highway. • The real CO 2 transport distance was reduced. • In-situ polymerization intensifies the interface affinity between ZIF-8 and PEO. The hollow filler has been verified to effectively enhance the CO 2 permeability of mixed matrix membrane (MMMs) by constructing low-resistance transport pathway. However, the in-continuity of hollow fillers across the membrane results in insufficient CO 2 permeability. In this work, the micron-sized hollow ZIF-8 (Mic-H-ZIF-8) were designed and proposed to accumulate continuously across the membrane to construct the transport highway for CO 2. Importantly, the in-situ polymerization was utilized to achieve continuous accumulation of the Mic-H-ZIF-8 fillers across the membrane. The Mic-H-ZIF-8 presents cavity size of 4 μm and shell thickness of 100 nm, and three or four Mic-H-ZIF-8 microspheres are aligned sequentially across the membrane, in which the effective gas transport distance is decreased from 13 μm to the range of 0.8–3 μm. Consequently, the CO 2 permeability of 5 wt% Mic-H-ZIF-8/PEO MMM is 224.6 % and 63.5 % higher than those of pure PEO membrane and nanosized hollow ZIF-8/PEO MMM at 0.1 MPa. Meanwhile, the CO 2 /N 2 selectivity is still as high as 70.0. This CO 2 separation performance is far exceeding the Robeson upper bound in 2008, and beyond the McKeown upper bound in 2019 as the feed pressure increasing, confirming the significance of continuous transport highway constructed by micron-sized hollow MOFs on improving CO 2 separation of MMMs. [ABSTRACT FROM AUTHOR]

Facilitated transport membrane with fixed and mobile carriers is essential yet challenging to improve the CO 2 capture. Herein, a facilitated transport membrane with continuous pathway was constructed by the in-situ interlinkage of mobile aniline with the fixed carriers distributing along electrospun polyacrylonitrile (PAN) nanofibers. In this membrane, fixed amine carriers are introduced through the alkalinous hydrolysis of PAN fibers (HPAN), and are distributed along the HPAN fibers to construct a long-range continuous transport pathway for CO 2. The mobile aniline carriers are introduced into the interfibrous voids of the HPAN nanofibers mat (NFM) by in-situ polymerization of Poly (ethylene glycol) diacrylate (PEGDA), which interlink the fixed amine carriers to achieve the facilitated transport pathway continuous completely. And the fixed amine and mobile aniline carriers are demonstrated to co-exist in the An/PEO@HPAN membrane (NFCM) by the FTIR and XPS results. Meanwhile, the XRD and DSC results indicate that the introduction of aniline increases the free volume of PEO matrix, which is beneficial for enhancing CO 2 permeation. Therefore, the 10 wt% An/PEO@HPAN-3h NFCM presents 90.81 % and 13.15 % increases in CO 2 permeability and CO 2 /N 2 selectivity under mixed gas at 0.3 MPa in contrast with the membrane without mobile aniline carriers. Under mixed gas conditions, this NFCM exhibits CO 2 permeability of 202.93 Barrer and CO 2 /N 2 selectivity of 83.89 at 0.1 MPa, reaching the 2019 McKeown upper bound. [Display omitted] • Fixed amine carriers are distributed along the HPAN nanofibers. • Mobile aniline carriers are introduced with in-situ polymerization of PEGDA. • Aniline interlinks the long-range continuous transport pathway in short range. • Continuous facilitated transport pathway improves CO 2 permeability. [ABSTRACT FROM AUTHOR]