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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Composition and microstructure of zirconium and hafnium germanates obtained by different chemical routes

The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. The products were characterized using high-temperature X-ray diffraction analysis (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and thermal (TG/DTA) analysis. To investigate the phase composition and stoichiometry of compounds the unit cell parameters were refined by full-profile Rietveld XRD analysis. The morphology of products and its evolution during high-temperature treatment was examined by SEM analysis. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. The ceramic route requires a multi-stage high-temperature treatment to obtain zirconium and hafnium germanates of 95% purity or more. Also, there are strong diffusion limitations to obtain hafnium germanate Hf{sub 3}GeO{sub 8} by ceramic route. On the contrary, the co-precipitation route leads to the formation of nanocrystalline single phase germanates of stoichiometric composition at a relatively low temperatures (less than 1000 °C). The results of quantitative XRD analysis showed the hafnium germanates are stoichiometric compounds in contrast to zirconium germanates that form a set of solid solutions. This distinction may be related to the difference in the ion radii of Zr and Hf. - Graphical abstract: The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. Display Omitted - Highlights: • Zr and Hf germanates were synthesized by ceramic and co-precipitation routes. • The morphology of products depends on the synthesis parameters. • Zirconium germanates forms a set of solid solutions. • Hafnium germanates are stoichiometric compounds.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Fabrication and Analysis of Tri-layer YBa{sub 2}Cu{sub 3}O{sub 7−δ} Thick Films by Low-Fluorine MOD Method

Improving the thickness of superconducting layer in coated conductors is an effective way to enhance its critical current. In this work, tri-layer YBCO/YBCO/YDyBCO films were successfully deposited on buffered Hastelloy substrate using the multi-coating lowfluorine metal-organic decomposition (LF-MOD) method and the thickness of the films can be up to 2.4 μ m. The effects of high-temperature annealing time on microstructures and superconducting properties of the films were systematically studied. Energy dispersive X-ray spectroscopy (EDS) results reveal that there remains a large amount of F element in the upper layer of the film when the annealing time is too short. With increasing the annealing time, the fluoride-containing precursor converts to YBCO grains completely. But the coarsening of grains appeared, and the critical current density (J{sub c}) of the film dropped slightly when the annealing time is too long. The cross-sectional scanning electron microscope (SEM) image and EDS plane analysis were applied to investigate the microstructure and element distribution of the final triple-layer YBCO films, respectively. The critical current of the final YBCO superconducting film could reach 316 A (77 k, self-field) for 1.2-cm-wide tapes with the optimal annealing conditions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2015

The controllable assembly of nanorods, nanowires and microwires of a perylenediimide molecule with photoswitching property

By using an electron donor–acceptor molecule that consists of a perylenediimide (PDI) core bonded with two ferrocene (Fc) units, well-defined nanorods, nanowires and microwires of PDI-Fc were formed through simply adjusting the initial concentration of PDI-Fc in dichloromethane or CH{sub 2}Cl{sub 2}. Moreover, the two-ended devices based on individual microwire were fabricated. Highly reproducible and sensitive photo response characteristics were demonstrated in the microwire through controlling the white light on and off with different light intensities. The assembly strategy via complementary donors and acceptors is of significance for constructing photoconductive systems and developing novel functional devices. - Graphical abstract: The two-ended devices based on individual microwire were fabricated. Highly reproducible and sensitive photo response characteristics were observed by controlling the white light on and off with different light intensities. - Highlights: • An electron donor–acceptor molecule (PDI-Fc) was synthesized. • Well-defined nanorods, nanowires and microwires of PDI-Fc were formed. • The two-ended devices based on individual microwire were fabricated. • Highly reproducible and sensitive photo response characteristics were observed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Effects of sintering temperature and duration on the structural and electrical properties of CuBiS{sub 2} bulks

CuBiS{sub 2} bulks were prepared by reactive sintering the mixture of Cu{sub 2}S and Bi{sub 2}S{sub 3} at 300, 350, 400, and 450 °C for 2 h and at the sintering temperature of 400 °C for 1, 1.5, 2, 2.5, and 3 h under a compensation disc of CuS for atmospheric control. Composition, structure, morphology, and electrical properties of the sintered bulks were analyzed. The compositions of Cu, Bi, and S did not change until the temperature reached at 450 °C.The highest electrical conductivity of 4.3 S cm{sup −1} and the highest Hall mobility of 11.1 cm{sup 2} V{sup −1} s{sup −1} were obtained for CuBiS{sub 2} sintered at 400 °C for 2 h. The deviation in the S/(Cu+Bi) ration caused the degradation of electrical properties, though the CuBiS{sub 2} remained as a single phase. Therefore, CuBiS{sub 2}, a less studied ternary copper based sulfide, is the p-type semiconductor for potential energy-related application and needs to have a good control in composition. - Graphical abstract: CuBiS{sub 2}, a less studied ternary copper based sulfide, is the p-type semiconductor and needs to have a good control in composition to achieve the optimal electrical properties. - Highlights: • CuBiS{sub 2}, a less studied copper-based sulfide, is a p-type semiconductor. • Electrical properties of CuBiS{sub 2} are important for its photovoltaic applications. • Deviation in composition leads a change in the electrical properties of CuBiS{sub 2}. • n of 2.4×10{sup 18} cm{sup −3}, μ of 11.1 cm{sup 2} V{sup −1} s{sup −1}, and σ of 4.3 S cm{sup −1} were obtained. • The process control in CuSbS{sub 2} is critical to achieve consistent performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Synthesis, characterization, and controlled release antibacterial behavior of antibiotic intercalated Mg–Al layered double hydroxides

Graphical abstract: The antibiotic anion released from Mg–Al LDHs provides a controlled release antibacterial activity against the growth of Micrococcus lysodeikticus in 3.5% NaCl solution. Highlights: ► Antibiotic anion intercalated LDHs were synthesized and characterized. ► The ion-exchange one is responsible for the release process. ► The diffusion through particle is the release rate limiting step. ► LDHs loaded with antibiotic anion have high antibacterial capabilities. -- Abstract: Antibiotic–inorganic clay composites including four antibiotic anions, namely, benzoate (BZ), succinate (SU), benzylpenicillin (BP), and ticarcillin (TC) anions, intercalated Mg–Al layered double hydroxides (LDHs) were synthesized via ion-exchange. Powder X-ray diffraction and Fourier transform infrared spectrum analyses showed the successful intercalation of antibiotic anion into the LDH interlayer. BZ and BP anions were accommodated in the interlayer region as a bilayer, whereas SU and TC anions were intercalated in a monolayer arrangement. Kinetic simulation of the release data indicated that ion-exchange was responsible for the release process, and the diffusion through the particles was the rate-limiting step. The antibacterial capabilities of LDHs loaded with antibiotic anion toward Micrococcus lysodeikticus growth were analyzed using a turbidimetric method. Significant high inhibition rate was observed when LDH nanohybrid was introduced in 3.5% NaCl solution. Therefore, this hybrid material may be applied as nanocontainer in active antifouling coating for marine equipment.

36 MATERIALS SCIENCE↗
DOE OSTI2014

One-step synthesis of dense and spherical nanostructured V{sub 2}O{sub 5} particles for cathode of lithium batteries and their electrochemical properties

Graphical abstract: Dense and spherical nanostructured V{sub 2}O{sub 5} particles. - Highlights: • One-step synthesis of dense, spherical, nanostructured V{sub 2}O{sub 5} particles was achieved. • As-prepared V{sub 2}O{sub 5} consists of primary particles of approximately 100 nm size. • The electrochemical performance of spherical nanostructured V{sub 2}O{sub 5} was investigated. • The potential range affects to the discharge capacity and cyclability of V{sub 2}O{sub 5}. - Abstract: A one-step synthesis of V{sub 2}O{sub 5} was directly achieved via ultrasonic spray pyrolysis at various synthesis temperatures ranging from 500 to 700 °C. The V{sub 2}O{sub 5} prepared at 500 °C is dense and spherical nanostructured particles, which consist of primary particles with a size of approximately 100 nm. The morphology change remarkably progresses with increasing synthesis temperatures from 500 to 700 °C. The electrochemical performance of a cathode comprising dense and spherical nanostructured V{sub 2}O{sub 5} particles prepared at 500 °C was investigated by galvanostatic discharge–charge cycling and cyclic voltammetry. From the discharge–charge cycling, the initial discharge capacity of the cathode was found to be about 403 mAh g{sup −1} in the potential range of 1.5–4.0 V, but it decreased owing to inherent phase changes with repeated cycling. The potential range significantly affects the cycle performance, and the V{sub 2}O{sub 5} cathode showed good cycle performance in the potential range of 2.5–4.0 V.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Meso-porous α-Fe{sub 2}O{sub 3} thin films synthesized via the sol-gel process for light-driven water oxidation

This work reports a facile and cost-effective method for synthesizing photoactive α-Fe{sub 2}O{sub 3} films as well as their performances when used as photoanodes for water oxidation. Transparent α-Fe{sub 2}O{sub 3} meso-porous films were fabricated by template-directed sol-gel chemistry coupled with the dip-coating approach, followed by annealing at various temperatures from 350 degrees C to 750 degrees C in air. α-Fe{sub 2}O{sub 3} films were characterized by X-ray diffraction, XPS, FE-SEM and electrochemical measurements. The photoelectrochemical performance of α-Fe{sub 2}O{sub 3} photoanodes was characterized and optimized through the deposition of Co-based co-catalysts via different methods (impregnation, electro-deposition and photo-electro-deposition). Interestingly, the resulting hematite films heat-treated at relatively low temperature (500 degrees C), and therefore devoid of any extrinsic dopant, achieve light-driven water oxidation under near-to-neutral (pH = 8) aqueous conditions after decoration with a Co catalyst. The onset potential is 0.75 V vs. the reversible hydrogen electrode (RHE), thus corresponding to 450 mV light-induced under potential, although modest photocurrent density values (40 μAcm{sup -2}) are obtained below 1.23 V vs. RHE. These new materials with a very large interfacial area in contact with the electrolyte and allowing for a high loading of water oxidation catalysts open new avenues for the optimization of photo-electrochemical water splitting. (authors)

08 HYDROGEN↗
DOE OSTI2015

Effects of additions of carbon nanotubes on the thermoelectric properties of Ni{sub 0.05}Mo{sub 3}Sb{sub 5.4}Te{sub 1.6}

To prepare Ni{sub 0.05}Mo{sub 3}Sb{sub 5.4}Te{sub 1.6}, the starting materials were loaded in the stoichiometric ratio into silica tubes and then heated at 1000 K. The reaction products were mixed and divided into four equal parts. The first sample was used as a reference sample called bulk. For the remaining samples, 1%, 2% and 3% by mass of MWCNT (multi-wall carbon nanotubes) were added by ball-milling. These materials were then subjected to consolidation by hot-pressing at 850 K and 56 MPa. Their transport properties were determined and compared to study the influence of MWCNT on the transport properties of Ni{sub 0.05}Mo{sub 3}Sb{sub 5.4}Te{sub 1.6}. Scanning and transmission electron microscopy were used to study the microstructural and nanostructural features of the samples, and Raman characterization was performed to look for changes induced by ball-milling and hot-pressing of the nanotubes. Mainly due to a largely reduced thermal conductivity by 40% and a slightly reduced power factor, the figure-of-merit was improved by 25% after addition of 3 mass% of MWCNT. - Graphical abstract: Figure-of-merit of various Ni{sub 0.05}Mo{sub 3}Sb{sub 5.4}Te{sub 1.6}/CNT composites. - Highlights: • Various composites of Ni{sub 0.05}Mo{sub 3}Sb{sub 5.4}Te{sub 1.6} with carbon nanotubes were synthesized and characterized. • In each case, the thermoelectric figure-of-merit increases rapidly with increasing temperature. • With increasing amount of carbon nanotubes, the thermal conductivity decreases more than the electrical conductivity. • The composite with 3% carbon nanotubes performs better than the bulk material by 25%.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Monoclinically distorted perovskites, A{sub 2}ZnTiO{sub 6} (A=Pr, Gd): Rietveld refinement, and dielectric studies

Double perovskite related oxide A{sub 2}ZnTiO{sub 6}A=Pr, Gd were synthesized by the solid state reaction method at 1523 K. The structure and microstructure of the compounds were studied by X-ray, SAED and FESEM. Rietveld refinement of the powder X-ray analysis shows that the compounds crystallizes in monoclinic space group P2{sub 1}/n (a{sup +}b{sup −}b{sup −}) with unit cell parameter √2a{sub p}×√2a{sub p}×2a{sub p} (a=5.5026(1) Å, b=5.6305(1) Å, c=7.8149(1) Å, β=90.02(1)° for Pr{sub 2}ZnTiO{sub 6} and a=5.3621(1) Å, b=5.6565(2) Å, c=7.6779(2) Å and β=90.264(2)° for Gd{sub 2}ZnTiO{sub 6}. Electron diffraction study confirms P2{sub 1}/n symmetry of the oxides. The monoclinic distortion is larger in Gd{sub 2}ZnTiO{sub 6} than Pr{sub 2}ZnTiO{sub 6} which is associated with the tolerance factor and the tilting angle of ZnO{sub 6} and TiO{sub 6} octahedra (ϕ=13.64° for Pr{sub 2}ZnTiO{sub 6} and 16.51° for Gd{sub 2}ZnTiO{sub 6}). The compounds are highly ordered. The charge and size difference between B site cations are the driving force for the ordering of the B′O{sub 6} and B″O{sub 6} octahedra. Pr{sub 2}ZnTiO{sub 6} shows a dielectric constant of 27 and dielectric loss of 0.003 while Gd{sub 2}ZnTiO{sub 6} has a dielectric constant of 17 and dielectric loss of 0.005 measured at 1 MHz. - Graphical abstract: Synthesis of new double perovskite dielectric material with very low dielectric loss. - Highlights: • Synthesis of new monoclinically distorted double perovskite (Pr{sub 2}ZnTiO{sub 6}). • Synthesis of monoclinically distorted double perovskite (Gd{sub 2}ZnTiO{sub 6}). • Selected area electron diffraction study of A{sub 2}ZnTiO{sub 6} (A=Pr, Gd). • Study of dielectric properties of A{sub 2}ZnTiO{sub 6} (A=Pr, Gd)

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRSDate not supplied

Investigating Space Weathering Effects on Carbonaceous Asteroids Using High-flux and Low-flux Ion Irradiation of the Murchison Meteorite

Airless planetary bodies are continuously altered by space weathering processes such as solar wind irradiation and micrometeoroid bombardment. These processes change the microstructural, chemical, and optical properties of planetary regoliths and, in turn, complicate interpretations of surface composition from remote sensing data. Previous space weathering investigations have focused primarily on lunar and ordinary chondrite materials, the latter of which have been directly linked to S-type asteroids [1]. However, relatively little is known about space weathering of primitive carbonaceous chondrites, which contain a combination of hydrous silicate and organic phases and are hypothesized to be fragments of C-complex asteroids [2]. To address this knowledge gap and maximize the science return of missions targeting C-complex asteroids (e.g., NASA OSIRIS-REx targeting Bennu and JAXA Hayabusa2 targeting Ryugu)[3-4], we examine the spectral, microstructural, and chemical effects of simulated solar wind weathering on a carbonaceous asteroid analog material. Here, we present the results from coordinated analyses of Murchison (CM2) meteorite slabs irradiated with 1 keV/amu H+ and He+ ions.

space weathering↗
DOE OSTI2012

Incubational domain characterization in lightly doped ceria

Microstructures of both Gd- and Y-doped ceria with different doping level (i.e., 10 at% and 25 at%) have been comprehensively characterized by means of high resolution transmission electron microscopy and selected area electron diffraction. Coherent nano-sized domains can be widely observed in heavily doped ceria. Nevertheless, it was found that a large amount of dislocations actually exist in lightly doped ceria instead of heavily doped ones. Furthermore, incubational domains can be detected in lightly doped ceria, with dislocations located at the interfaces. The interactions between such linear dislocations and dopant defects have been simulated accordingly. As a consequence, the formation mechanism of incubational domains is rationalized in terms of the interaction between intrinsic dislocations of doped ceria and dopant defects. This study offers the insights into the initial state and related mechanism of the formation of nano-sized domains, which have been widely observed in heavily rare-earth-doped ceria in recent years. - Graphical abstract: Interactions between dislocations and dopants lead to incubational domain formation in lightly doped ceria. Highlights: Black-Right-Pointing-Pointer Microstructures were characterized in both heavily and light Gd-/Y-doped ceria. Black-Right-Pointing-Pointer Dislocations are existed in lightly doped ceria rather than heavily doped one. Black-Right-Pointing-Pointer Interactions between dislocations and dopant defects were simulated. Black-Right-Pointing-Pointer Formation of dislocation associated incubational domain is rationalized.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Entropy-Driven Charge Separation: A Potential Explanation for the Low Energy Loss Found in OPVs with Non-fullerene Acceptors

The recent development of non-fullerene acceptors (NFA) has led to an abrupt increase in the organic photovoltaic (OPV) efficiency from ~12% to ~20%. NFA OPVs can generate photocurrent efficiently without much energy loss, which contrasts with the large energy loss often needed for generating free charges from excitons in fullerene OPVs. Here, we argue that entropy-driven charge separation, which allows excitons to spontaneously gain heat from the environment, is responsible for the exceptionally low energy loss found in NFA OPVs. The entropic driving force is maximized when the delocalized electron and hole wave functions in the CT exciton intersect each other via pointlike junctions. Furthermore, these pointlike junctions are abundant in the polymer/NFA bulk heterojunction which consists of intertwined, stringlike donor and acceptor domains in which electron delocalizes anisotropically. Such microstructure favors entropy-driven charge separation, which can enable charge separation with a minimal energy loss.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Correlation between processing conditions, microstructure and charge transport in half-Heusler alloys

Five bulk samples of n-type Zr₀.₂₅Hf₀.₇₅NiSn₀.₉₇₅Sb₀.₀₂₅ half-Heusler (HH) alloy were fabricated by reacting elemental powders via (1) high temperature solid state (SS) reaction and (2) mechanical alloying (MA), followed by densification using spark plasma sintering (SPS) and/or hot pressing (HP). A portion of the sample obtained by SS reaction was mechanically alloyed before consolidation by hot pressing (SS–MA–HP). X-ray powder diffraction and transmission electron microscopy studies revealed that all SS specimen (SS–SPS, SS–HP, SS–MA–HP) are single phase HH alloys, whereas the MA sample (MA–SPS) contains metallic nanoprecipitates. Electronic and thermal transport measurements showed that the embedded nanoprecipitates induce a drastic increase in the carrier concentration (n), a large decrease in the Seebeck coefficient (S) and a marginal decrease in the lattice thermal conductivity (κ l ) of the MA–SPS sample leading to lower ZT values when compared to the SS–HP samples. Constant values of S are observed for the SS series regardless of the processing method. However, a strong dependence of the carrier mobility (μ), electrical conductivity (σ) and κ l on the processing and consolidation method is observed. For instance, mechanical alloying introduces additional structural defects which enhance electron and phonon scattering leading to moderately low values of μ and large reduction in κ l . This results in a net 20% enhancement in the figure of merit (ZT=0.6 at 775 K). HH specimen of the same nominal composition with higher ZT is anticipated from a combination of SS reaction, MA and SPS (SS–MA–SPS). - Graphical abstract: In half-Heusler alloys, thermopower values are insensitive to processing method, whereas carrier mobility (μ), electrical conductivity (σ), and κ l strongly dependent on the microstructure which in turn is altered by the synthesis, processing and consolidation method. Highlights: • Phase composition of HH alloy strongly depends on the synthesis technique. • Mechanical alloying of elements yields bulk HH alloy with metallic impurity phases. • Thermopower, carrier density, and effective mass of HHs are insensitive to processing conditions. • Mechanical alloying decreases the carrier mobility and lattice thermal conductivity of bulk HH.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Dislocation cross-slip in precipitation hardened Mg–Nd alloys

An integrated experimental characterization and molecular dynamics (MD) simulation approach was used to explore the dislocation-precipitate interactions in a dilute Magnesium–Neodymium (Mg–Nd) precipitation hardened alloy. In situ indentation in a transmission electron microscope (TEM) and postmortem TEM characterization of deformed samples and MD simulations revealed that basal < a > type dislocations interacted differently with β 1 (Mg 3 Nd) and β"(Mg 3-7 Nd) precipitates. For β" precipitates, the basal dislocations directly shear the precipitates. For β 1 precipitates, such shearing becomes much more difficult because it requires the creation of antiphase boundaries in the ordered lattice of β 1 precipitates. Screw dislocations were observed to cross-slip from basal to the prismatic plane, which could be parallel to the broad facet of β 1 precipitates. It is postulated that double cross-slip (basal to prismatic to basal) via the Hirsch mechanism may enable screw dislocations to overcome the β 1 precipitates. MD simulations also revealed that an edge dislocation is unable to bypass the precipitate via the generation of screw dislocation segments plus the double cross-slip mechanism. The edge dislocation can bow around the precipitate, and the segment that adopts a screw character can cross-slip to the prismatic plane but with increasing applied stress, cross-slips back to the original basal plane to continue glide via precipitate shearing. Finally, the implication of glide dislocation - β 1 -precipitate interaction mechanisms on the strength and ductility of β 1 precipitate dominant microstructures is discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2022

X-ray ptychographic tomography reveals buried 3D structural defects in metal halide perovskites

For the first of its kind, X-ray ptychographic imaging is utilized for probing metal halide perovskite crystals, revealing various 3D structural defects fully or partially buried underneath the perovskite surface. Here, this work demonstrates a powerful, non-intrusive 3D tomographic characterization method to illuminate the complete microstructure of perovskites for advanced energy applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Crosslinked Matrimid®-like polyimide membranes with unimodal network structure for enhanced stability and gas separation performance

Gas separation membranes have attracted academic and industrial attention, and crosslinking has been identified to be one of the most effective ways to enhance membrane stability. In this paper, a series of crosslinked Matrimid®-like films with unimodal network structures are prepared via thermally end-linking phenylethnyl-terminated BTDA-DAPI oligomers with well-controlled molecular weight (i.e., 3000–15,000 g/mol), wherein the crosslink density (the inter-crosslink chain length) of resulting unimodal networks is systematically varied by using oligomers with various molecular weight. Comprehensive characterizations of chemical structure, thermal properties, microstructures are performed. Pure-gas permeation measurements are performed focusing on H 2 /CH 4 and CO 2 /CH 4 separations as a function of crosslink density. In sharp contrast to the commonly observed permeability reduction in randomly crosslinked networks, all the crosslinked unimodal films, even when densely crosslinked, present markedly enhanced permeability and well-maintained ideal selectivity relative to the uncrosslinked linear counterpart, leading to almost horizontal movements towards upper bounds along with expectedly enhanced membrane stability. In conclusion, it is concluded that introducing bulky groups at the crosslink sites provide a practical means to counteract the densification effect induced by crosslinking and the construction of unimodal networks exemplifies a fundamentally new strategy to regulate the microstructure and property of crosslinked membranes for gas separations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗