With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separatio...With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separation cannot be neglected since,compared with other conventional process,membrane-based process is more effective and consumes less energy.Regarding this,metal-based membranes,particularly palladium,are usually employed for hydrogen separation because of its high selectivity.However,with the advancement of various microporous materials,the status quo of the metal-based membranes could be challenged since,compared with the metal-based membranes,they could offer better hydrogen separation performance and could also be cheaper to be produced.In this article,the advancement of membranes fabricated from five main microporous materials,namely silica-based membranes,zeolite membranes,carbon-based membranes,metal organic frameworks/covalent organic frameworks(MOF/COF)membranes and microporous polymeric membranes,for hydrogen separation from light gases are extensively discussed.Their performances are then summarized to give further insights regarding the pathway that should be taken to direct the research direction in the future.展开更多
Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （SAPO） microporous materials. A comparative stu...Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （SAPO） microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer （PSA） and scanning electron microscope （SEM）. The PSA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test （F-test） methods were performed for the significance of results by the analysis of variance （ANONA） and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett ＆ Teller （BET） volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials.展开更多
With the increasing demand for synthetic rubber,the purification of 1,3-butadiene(C_(4)H_(6))is of great industrial significance.Herein,the successful removal of n-butene(n-C_(4)H_(8))and iso-butene(iso-C_(4)H_(8))fro...With the increasing demand for synthetic rubber,the purification of 1,3-butadiene(C_(4)H_(6))is of great industrial significance.Herein,the successful removal of n-butene(n-C_(4)H_(8))and iso-butene(iso-C_(4)H_(8))from 1,3-butadiene(C_(4)H_(6))was realized by synthesizing a novel TaOF_(5)^(2-) anion-pillared ultramicroporous material TaOFFIVE-3-Ni(also referred to as ZU-96,TaOFFIVE=TaOF_(5)^(2-),3=pyrazine).Single-component adsorption isotherms show that TaOFFIVE-3-Ni can achieve the exclusion of n-C_(4)H_(8) and iso-C_(4)H_(8) in the low pressure region(0–30 kPa),and uptake C_(4)H_(6) with a high capacity of 92.78 cm^(3)·cm^(-3)(298 K and 100 kPa).The uptake ratio of C_(4)H_(6)/iso-C_(4)H_(8) on TaOFFIVE-3-Ni was 20.83(298 K and 100 kPa),which was the highest among the state-of-the-art adsorbents reported so far.With the rotation of anion and pyrazine ring,the pore size changes continuously,which makes smaller-size C_(4)H_(6) enter the channel while larger-size n-C_(4)H_(8) and iso-C_(4)H_(8) are completely blocked.The excellent breakthrough performance of TaOFFIVE-3-Ni shows great potential in industrial separation of C4 olefins.The specific adsorption binding sites within ZU-96 was further revealed through the modeling calculation.展开更多
In the domain of gas adsorption and separation,microporous materials have garnered considerable attention due to their elevated specific surface area and pore structure[1].And the dissolution of gases in liquids is li...In the domain of gas adsorption and separation,microporous materials have garnered considerable attention due to their elevated specific surface area and pore structure[1].And the dissolution of gases in liquids is limited by unstable liquid-phase pores and weak gas-liquid interactions,which leads to low solubility.However,conventional microporous materials are predominantly solid-state,which complicates their direct adsorption and separation application in liquid environments.展开更多
Zeolites are crystalline microporous materials widely used in catalysis,adsorption,and ion exchange owing to their tunable pore structures and acid centers[1].Traditional zeolites,however,often suffer from limitations...Zeolites are crystalline microporous materials widely used in catalysis,adsorption,and ion exchange owing to their tunable pore structures and acid centers[1].Traditional zeolites,however,often suffer from limitations such as restricted molecular diffusion and rapid coking,which hinder their efficiency in processing large molecules.展开更多
The photochemical behavior of polyoxometalates（POMs）have been studied extensivelyIn homogeneous solutions［1-3]．However，the major drawback to the practical applications ofthe homogeneous systems is the high ...The photochemical behavior of polyoxometalates（POMs）have been studied extensivelyIn homogeneous solutions［1-3]．However，the major drawback to the practical applications ofthe homogeneous systems is the high water solubility of POMs，which impedes the readyrecovery and the reuse of the photocatalysts．Therefore，the preparation of insoluble POMs Isconsidered．More recently，we haveprepared insoluble POMs，i．e，Keggin－type microporousPOMs，H3PW12O40／SiO2 or H4SiW12O40／SiO2，and paratungstate A－containing pillaredcompound，Mg12Al6（OH）36（W7O24）·4H2O，for the purpose of photo－oxidation of aqueous展开更多
Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD （X-ray diffra...Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD （X-ray diffraction）, SEM （scanning electron microscope）, TG （thermal gravimetric analysis）, ICP （inductively coupling plasma） elemental analysis, nitrogen sorption isotherm and surface area. The results show that pure SUZ-4 zeolites with high crystallinity are obtained in a broad window of synthesis conditions： seed mass concentration 0.2%-2%, SIO2/A1203 molar ratio 21 25, KOH/SiO2 molar ratio 0.33 0.43, H20/SiO2 molar ratio 7.14-38.1, aging time 24 h, crystallization temperature 160℃, and crystallization time 6-10 d. Also, crystallinity and size of the rod-like SUZ-4 zeolite crystals are found to alter with the conditions.展开更多
A novel synthesis process for ETS-4 titanosilicate using commercial anatase as the titanium source in the absence of fluoride ions was studied. Fluoride ions and traced ETS-4 seeds have important roles in forming ETS-...A novel synthesis process for ETS-4 titanosilicate using commercial anatase as the titanium source in the absence of fluoride ions was studied. Fluoride ions and traced ETS-4 seeds have important roles in forming ETS-4 structures. However, the method using ETS-4 seeds instead of fluoride ions to improve product purity and productivity is environment-friendly. ETS-4, ETS-4（NS）, and ETS-4（NaF） were respectively synthesized using traced ETS-4 seeds, without seeds, and with fluoride ions. The as-synthesized samples were identified by X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. Adsorption isotherms and adsorption heats of nitrogen and methane on the prepared ETS-4 were also measured. The results showed that ETS-4 samples could be prepared using anatase in the absence of fluoride ions, with good purity, comparable physicochemical properties, and excellent adsorption properties.展开更多
Porous silicon carbide/carbon （SiC/C） microspherules were prepared by the controlled heating treatment of polymer and silica hybrid precursors over 1000℃ in Ar/H2 stream. The resultant SiC/C composite shows improve...Porous silicon carbide/carbon （SiC/C） microspherules were prepared by the controlled heating treatment of polymer and silica hybrid precursors over 1000℃ in Ar/H2 stream. The resultant SiC/C composite shows improved physical properties such as excellent mechanical strength, regular physical form, and high packing density. Such improvement overcomes the main inherent problems encountered when using activated carbons as absorbents without sacrificing porosity properties. N2 sorption analysis shows that the SiC/C composite has a BET surface area of 1793 m^2/g and a pore volume of 0.92 ml/g. Methane adsorption isotherm is determined by the conventional volumetric method at 25℃ and up to 7.0 MPa. On volumetric basis, the SiC/C composite microspherules show methane storage of 145 （V/V） at 3.5 MPa and 25℃. The combination of excellent physical properties and porosity properties in this SiC/C composite lends a great possibility to develop a competitive storage system for natural gas.展开更多
Optoelectronic nanocomposites are a new class of materials, which exhibit very interesting and particular properties and attract a growing attention due to their potential applications in information storage and optoe...Optoelectronic nanocomposites are a new class of materials, which exhibit very interesting and particular properties and attract a growing attention due to their potential applications in information storage and optoelectronic devices. Zinc oxide, ZnO, is one of the most interesting binary semiconductor （3.37 eV） with very important optical properties, which can be used in the fields such as short wavelength lasers, blue light emitting diodes, UV detectors, gas sensors, etc. This paper reviews the very recent progress in the prepa- ration of silica-based ZnO nanocomposites. After an introduction reviewing the theoretical background, the article will begin with a survey of the optical properties and the quantum size effect （QSE） of ZnO/SiO2 nanocomposites prepared by the inclusion of ZnO nanoclusters inside silica mesoporous materials. The second part will focus on one of the most interesting properties of ZnO/SiO2 nanocomposites, which is the random lasing effect after one- and two-photon excitation. The final part will deal with the introduction of ZnO nanoparticles inside microporous zeolites and the observation of QSE. For comparison, the photoluminescence （PL） and QSE properties of ZnS nanoparticles occluded in mesoporous media are also described. New potential applications will be discussed since short-wavelength devices are required by industry to design, for instance, new information storage supports and biolabelling devices.展开更多
Comprehensive Summary Carbon dioxide(CO_(2))capture is one of the most important aspects of reducing global warming.In terms of CO_(2)capture,metal-organic frameworks(MOFs)have several advantages.However,it isn't ...Comprehensive Summary Carbon dioxide(CO_(2))capture is one of the most important aspects of reducing global warming.In terms of CO_(2)capture,metal-organic frameworks(MOFs)have several advantages.However,it isn't easy to shape MOFs while maintaining their performance.Herein,we describe the development of a pellet-shaped ultramicroporous MOF,Ni(3-ain)2(3-ain=3-aminoinoisonicotinic acid),that is capable of selectively adsorbing CO_(2).Polyvinyl butyral(PVB)is used as a binder during the production of Ni(3-ain)2 MOF pellets.The adequately shaped material can maintain its crystallinity and exhibit a high CO_(2)adsorption capacity(3.73 mmol·g^(-1))at ambient conditions,which is significantly greater than those obtained for N_(2)(0.63 mmol·g^(-1))and CO(0.90 mmol·g^(-1)).Consequently,this material displays high IAST selectivities for CO_(2)/N_(2)(26.3,15/85,V/V)and CO_(2)/CO(19.2,1/99,V/V).According to the theoretical calculations,Ni(3-ain)2 preferentially adsorbs CO_(2)molecules over N_(2)molecules and CO molecules.The results of experiments on dynamic breakthrough have demonstrated that Ni(3-ain)2 pellets are capable of effectively separating CO_(2)/N_(2)or CO_(2)/CO mixtures under conditions of dynamic flow.Furthermore,the structured MOF materials can be synthesized in one step at kilogram scale.This work provides an avenue for the shaping of MOFs for potential industrial applications in the future.展开更多
An imine-based nitrogen-rich covalent-organic framework(COF)was successfully synthesized using two tri-angular building units under solvothermal reaction condition.The gas adsorption properties of the obtained micro-p...An imine-based nitrogen-rich covalent-organic framework(COF)was successfully synthesized using two tri-angular building units under solvothermal reaction condition.The gas adsorption properties of the obtained micro-porous nitrogen-rich COF were investigated.The results indicated that the activated COF material presented good up take capabilities of CO_(2) and CH_(4) at 61.2 and 43.4 cm^(3)·g^(−1)at 1 atm and 273 K,respectively,showing its applica-tion potential in selective gas capture and separation.展开更多
Using microporous raw materials to prepare reticulated ceramic filters for molten steel purification is a novel strategy to enhance the purification efficiency.Steel immersion tests were conducted on two batches of pe...Using microporous raw materials to prepare reticulated ceramic filters for molten steel purification is a novel strategy to enhance the purification efficiency.Steel immersion tests were conducted on two batches of periclase-spinel ceramic filters prepared from microporous magnesia raw material and α-Al_(2)O_(3) micro-powder,and their performance was compared with pure MgO filter.The results showed that the periclase-spinel filters exhibited superior performance.This was attributed to two factors:first,the spinel microparticles within the filter skeletons had a greater advantage over magnesia microparticles in adsorbing spinel inclusions with similar chemical composition from the steel;second,the in-situ generated spinel increased the surface roughness of the skeletons and raised the contact angle between the filter and molten steel,thereby improving purification efficiency.When theα-Al_(2)O_(3) micro-powder content was 15 wt.%,the filter demonstrated excellent purification efficiency,the Al_(2)O_(3) and MgAl_(2)O_(4) inclusions in the molten steel were effectively removed,with an overall inclusion removal efficiency of 83.1%,and the total oxygen content in the steel decreased from 37.5×10^(−6) to 5.7×10^(−6),with a reduction of 84.8%.展开更多
CONSPECTUS:The separation and purification of hydrocarbons are crucially important processes in the petrochemical industry,as they are essential for producing high-quality chemicals and fuels.However,traditional therm...CONSPECTUS:The separation and purification of hydrocarbons are crucially important processes in the petrochemical industry,as they are essential for producing high-quality chemicals and fuels.However,traditional thermal-driven separation practices,such as cryogenic distillation,are notoriously energy-intensive,accounting for a notable portion of the energy consumption in industrial operations.This has spurred the exploration and development of low-energy and sustainable alternative separation technologies,among which adsorption/desorption-based separation with porous materials has gained significant attention.Metal−organic frameworks(MOFs)are emerging as ideal porous materials for hydrocarbon separation due to their exceptional porosity and structural tunability.This Account delves into the latest advancements in microporous MOFs for hydrocarbon separation,categorizing them based on their pore structures:single array,tandem array,and orthogonal array.Single-array MOFs feature uniformly arranged channel-like pores along the axial direction,facilitating the incorporation of binding sites on the pore surfaces.One notable functional group used in these applications is open metal sites(OMSs),which can engage in strong metal-πinteractions with unsaturated hydrocarbons such as acetylene.For example,JNU-1 demonstrates increased binding energy with the increasing pressure of acetylene due to the induce-fit effect,where framework contraction behavior is triggered by its OMSs.JNU-4 offers two binding sites per metal center for acetylene molecules,greatly improving the adsorption capacity.On the other hand,introducing low-polarity groups,as seen in JNU-6-CH3,can effectively enhance the separation performance in favor of alkanes while maintaining structural integrity under humid conditions.Another methyl group-modified MOF,JNU-5-CH3,exhibits an acetylene-triggered gateopening effect due to the multiple supramolecular interactions with acetylene.Tandem-array MOFs provide enhanced selectivity and adsorption capacity through the interconnection of spacious cavities with narrow apertures.For instance,JNU-2 with pore-channel interconnected structure exhibits improved separation efficiency for C2H6/C2H4 and hexane isomers.The slim channels connecting the large cavities act as screening sites for matching-sized molecules to pass through,while the large cavities function as storage sites for large adsorption capacity.Orthogonal-array MOFs,like JNU-3a,feature one-dimensional(1D)channels that enable rapid diffusion,complemented by molecular pockets on both sides that facilitate selective recognition.The dynamic“gourd-shaped”opening of the pocket demonstrates notable adaptability when interacting with different hydrocarbons,allowing for sieving-like behavior in the separation of propylene/propane,as well as efficient separation of ethylene from its mixtures with alkynes of various sizes.Overall,the designability and tunability of MOF pore structures make them promising candidates for effectively discriminating targeted molecules from multicomponent mixtures,offering energy-efficient solutions for challenging industrial separations.展开更多
Separating propylene(C_(3)H_(6))from propane(C_(3)H_(8))is a complex procedure in the petrochemical sector due to the comparable characteristics of the two gases.Herein,we reported the self-assembly phenomenon of NbOF...Separating propylene(C_(3)H_(6))from propane(C_(3)H_(8))is a complex procedure in the petrochemical sector due to the comparable characteristics of the two gases.Herein,we reported the self-assembly phenomenon of NbOFFIVE-1-Ni(KAUST-7)crystals under different synthetic routes.The material features a decreased framework strain energy compared to original KAUST-7 and exhibits completely different adsorption performance,achieving the efficient separation of C_(3)H_(6)/C_(3)H_(8) by synergetic effect of equilibrium and kinetics.The C.Headsorptiocapacitywas as highas 46.2cm^(3)·g^(-1)(298k.1bar),increasing by 3%compared to theoriginalmaterial.The difusion rates of C_(3)H_(6) were faster than C_(3)H_(8) as confirmed by time dependent kinetic adsorption profiles.It concurrently combines an excellent C_(3)H_(6)/C_(3)H_(8) uptake ratio of 3.1 and kinetic selectivity(96.5)for C_(3)H_(6)/C_(3)H_(8) separation with an equilibrium-kinetic combined selectivity of 42.5.Meanwhile,it can be regenerated easily due to moderate isosteric heat of adsorption(28.7 kJ·mol^(-1)).Breakthrough experiment for C_(3)H_(6)/C_(3)H_(8) gas mixture was conducted and confirmed the high-purity recovery of CsHs over CgHg.Moreover,it exhibited excellent water and moisture stability and can be easily synthesized through stirring at room temperature,which confers them with great potentialforindustrialapplication.展开更多
The zeolitic imidazolate framework-8 （ZIF-8） was successfully synthesized using ionic liquids as struc- ture-directing agent under microwave irradiation. Ionic liquids are green solvents with low vapour pressure and...The zeolitic imidazolate framework-8 （ZIF-8） was successfully synthesized using ionic liquids as struc- ture-directing agent under microwave irradiation. Ionic liquids are green solvents with low vapour pressure and good thermal stability. They are appropriate templates for microporous materials and ideal microwave absorbers. The microwave-assisted ionothermal synthesis applied in this paper was expected to be a promising method for the preparation of microporous materials. Results showed that the as-synthesized samples （300---500 nm in diameter） could be synthesized in a short time （60 min） and possessed regular morphology, stable structure and high thermal stability （up to 720 ~C in argon atmosphere）. Nitrogen adsorption-desorption test illustrated that samples produced by microwave heating had a higher surface area. Carbon dioxide adsorption test indicated that the samples synthe- sized by microwave heating had better carbon dioxide adsorption ability than those by conventional heating.展开更多
Three-dimensional(3D)covalent organic frameworks(COFs)are crystalline porous polymers with potential in numerous high-tech applications,but the linkages involved in their synthesis are still rather limited.Herein,we r...Three-dimensional(3D)covalent organic frameworks(COFs)are crystalline porous polymers with potential in numerous high-tech applications,but the linkages involved in their synthesis are still rather limited.Herein,we report novel 3D sp^(2) carbon-linked COFs fabricated by the formation reaction of C=C bonds and their application in fluorescence imaging.These new COFs,namely JUC-580 and JUC-581,show high stability and excellent light-emitting properties in solid state and dispersed in various solvents.Furthermore,we investigate the potential application of JUC-581 as a drug carrier combined with fluorescence imaging.These results indicate that 3D sp^(2) carbon-linked COFs are not only potential drug-loaded and sustained release materials but also promising cell fluorescent stains.This study thus expands the structural categories of 3D COFs based on different linkages,and promotes their prospective applications for biomedicine and fluorescent materials.展开更多
Solvothermal reactions of 3,6-di(pyridin-4-yl)-9H-carbazole(dpc)with Cu(ll)yielded crystals of two new coordination complexes,namely[Cu(CH_(3)COO)_(2)(dpc)(H_(2)O)_(2)]n-xvip(1)and[Cu_(13)(HCOO)_(16)(dpc)16(H_(2)O)6...Solvothermal reactions of 3,6-di(pyridin-4-yl)-9H-carbazole(dpc)with Cu(ll)yielded crystals of two new coordination complexes,namely[Cu(CH_(3)COO)_(2)(dpc)(H_(2)O)_(2)]n-xvip(1)and[Cu_(13)(HCOO)_(16)(dpc)16(H_(2)O)6](HCOO)10-vip(2),in which CH_(3)COO_and HCOO-were generated from the hydrolysis of the solvents A/zAZ-dimethylacetamide(DMA)and A/zA/-dimethylformamide(DMF),respectively.Single-crystal X-ray diffraction showed that 1 possesses simple wavy coordination chains,while 2 possesses large molecular bowls/sieves with outer and inner effective sizes of 30.2 × 30.2 × 25.5 A^(3) and 15.0 × 15.0 × 18.6 A^(3),respectively,which consists of 4 linear Cu_(3)(HCOO)_(4)(H_(2)O)clusters and 12 dpc ligands as the square-shaped wall and a claw-like Cu(dpc)_(4) fragment as the bottle.vip-free 2 can adsorb considerable amounts of CO_(2)/H_(2)O and CH_(3)OH but completely exclude C2H4 and C3H6z which shows a potential application for olefin drying.展开更多
The dilemma for the synthesis of covalent organic frameworks(COFs)is crystallinity and stability.Herein,we present the synthesis of a single-crystalline amide-linked COF,and demonstrate its excellent chemical as well ...The dilemma for the synthesis of covalent organic frameworks(COFs)is crystallinity and stability.Herein,we present the synthesis of a single-crystalline amide-linked COF,and demonstrate its excellent chemical as well as thermal stabilities.This study will inspire the synthesis of a wide spectrum of highly crystalline and stable COFs,promote their structure-property investigations and boost their applications in selective gas adsorption,storage and separation.展开更多
Utilizing solar energy for sorbent regeneration during the CO_(2)swing adsorption process could potentially reduce CO_(2)capture costs.This study describes a new technique—solar thermal swing adsorption(STSA)for CO_(...Utilizing solar energy for sorbent regeneration during the CO_(2)swing adsorption process could potentially reduce CO_(2)capture costs.This study describes a new technique—solar thermal swing adsorption(STSA)for CO_(2)capture based on application of intermittent illumination onto porous carbon monolith(PCM)sorbents during the CO_(2)capture process.This allows CO_(2)to be selectively adsorbed on the sorbents during the light-off periods and thereafter released during the light-on periods due to the solar thermal effect.The freestanding and mechanically strong PCMs have rich ultramicropores with narrow pore size distributions,displaying relatively high CO_(2)adsorption capacity and high CO_(2)/N_(2) selectivity.Given the high CO_(2)capture performance,high solar thermal conversion efficiency,and high thermal conductivity,the PCM sorbents could achieve high CO_(2)capture rate of up to 0.226 kg·kgcarbon^(-1)·h^(-1)from a gas mixture of 20 vol.%CO_(2)/80 vol.%N_(2) under STSA conditions with a light intensity of 1000 W·m^(-2).In addition,the combination of STSA with the conventional vacuum swing adsorption technique further increases the CO_(2)working capacity.展开更多
基金funding from the Alexander von Humboldt Postdoctoral Fellowship(Ref-3.3-GBR-1219268-HFST-P)。
文摘With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separation cannot be neglected since,compared with other conventional process,membrane-based process is more effective and consumes less energy.Regarding this,metal-based membranes,particularly palladium,are usually employed for hydrogen separation because of its high selectivity.However,with the advancement of various microporous materials,the status quo of the metal-based membranes could be challenged since,compared with the metal-based membranes,they could offer better hydrogen separation performance and could also be cheaper to be produced.In this article,the advancement of membranes fabricated from five main microporous materials,namely silica-based membranes,zeolite membranes,carbon-based membranes,metal organic frameworks/covalent organic frameworks(MOF/COF)membranes and microporous polymeric membranes,for hydrogen separation from light gases are extensively discussed.Their performances are then summarized to give further insights regarding the pathway that should be taken to direct the research direction in the future.
文摘Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （SAPO） microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer （PSA） and scanning electron microscope （SEM）. The PSA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test （F-test） methods were performed for the significance of results by the analysis of variance （ANONA） and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett ＆ Teller （BET） volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials.
基金supported by Natural Science Foundation of Zhejiang Province(LR20B060001 and LZ18B060001)the National Natural Science Foundation of China(21725603,21938011),the Entrepreneur Team Introduction Program of Zhejiang(2019R01006)the Research Computing Center in College of Chemical and Biological Engineering at Zhejiang University.
文摘With the increasing demand for synthetic rubber,the purification of 1,3-butadiene(C_(4)H_(6))is of great industrial significance.Herein,the successful removal of n-butene(n-C_(4)H_(8))and iso-butene(iso-C_(4)H_(8))from 1,3-butadiene(C_(4)H_(6))was realized by synthesizing a novel TaOF_(5)^(2-) anion-pillared ultramicroporous material TaOFFIVE-3-Ni(also referred to as ZU-96,TaOFFIVE=TaOF_(5)^(2-),3=pyrazine).Single-component adsorption isotherms show that TaOFFIVE-3-Ni can achieve the exclusion of n-C_(4)H_(8) and iso-C_(4)H_(8) in the low pressure region(0–30 kPa),and uptake C_(4)H_(6) with a high capacity of 92.78 cm^(3)·cm^(-3)(298 K and 100 kPa).The uptake ratio of C_(4)H_(6)/iso-C_(4)H_(8) on TaOFFIVE-3-Ni was 20.83(298 K and 100 kPa),which was the highest among the state-of-the-art adsorbents reported so far.With the rotation of anion and pyrazine ring,the pore size changes continuously,which makes smaller-size C_(4)H_(6) enter the channel while larger-size n-C_(4)H_(8) and iso-C_(4)H_(8) are completely blocked.The excellent breakthrough performance of TaOFFIVE-3-Ni shows great potential in industrial separation of C4 olefins.The specific adsorption binding sites within ZU-96 was further revealed through the modeling calculation.
基金support from the National Key R&D Program of China(2024YFE0101100)the National Natural Science Foundation of China(22305132,22475112,22365021)+2 种基金the Inner Mongolia Autonomous Region“Grassland Talents”Project(2024098)the Basic Research Expenses Supported under 45 Years Old of Inner Mongolia(23600-5233706)the Inner Mongolia Natural Science Foundation(2025LHMS02016).
文摘In the domain of gas adsorption and separation,microporous materials have garnered considerable attention due to their elevated specific surface area and pore structure[1].And the dissolution of gases in liquids is limited by unstable liquid-phase pores and weak gas-liquid interactions,which leads to low solubility.However,conventional microporous materials are predominantly solid-state,which complicates their direct adsorption and separation application in liquid environments.
基金the support of the National Natural Science Foundation of China(Nos.22205207 and 22378369).
文摘Zeolites are crystalline microporous materials widely used in catalysis,adsorption,and ion exchange owing to their tunable pore structures and acid centers[1].Traditional zeolites,however,often suffer from limitations such as restricted molecular diffusion and rapid coking,which hinder their efficiency in processing large molecules.
基金National Natural Science Foundation of China(No.20071007)and the Foundation for University KeyTeacher by the Ministry of Education of China.
文摘The photochemical behavior of polyoxometalates（POMs）have been studied extensivelyIn homogeneous solutions［1-3]．However，the major drawback to the practical applications ofthe homogeneous systems is the high water solubility of POMs，which impedes the readyrecovery and the reuse of the photocatalysts．Therefore，the preparation of insoluble POMs Isconsidered．More recently，we haveprepared insoluble POMs，i．e，Keggin－type microporousPOMs，H3PW12O40／SiO2 or H4SiW12O40／SiO2，and paratungstate A－containing pillaredcompound，Mg12Al6（OH）36（W7O24）·4H2O，for the purpose of photo－oxidation of aqueous
基金Supported by the National Natural Science Foundation of China(20976084,21101094,21136005)
文摘Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD （X-ray diffraction）, SEM （scanning electron microscope）, TG （thermal gravimetric analysis）, ICP （inductively coupling plasma） elemental analysis, nitrogen sorption isotherm and surface area. The results show that pure SUZ-4 zeolites with high crystallinity are obtained in a broad window of synthesis conditions： seed mass concentration 0.2%-2%, SIO2/A1203 molar ratio 21 25, KOH/SiO2 molar ratio 0.33 0.43, H20/SiO2 molar ratio 7.14-38.1, aging time 24 h, crystallization temperature 160℃, and crystallization time 6-10 d. Also, crystallinity and size of the rod-like SUZ-4 zeolite crystals are found to alter with the conditions.
基金supported by the National Natural Science Foundation of China (No. 51074205)
文摘A novel synthesis process for ETS-4 titanosilicate using commercial anatase as the titanium source in the absence of fluoride ions was studied. Fluoride ions and traced ETS-4 seeds have important roles in forming ETS-4 structures. However, the method using ETS-4 seeds instead of fluoride ions to improve product purity and productivity is environment-friendly. ETS-4, ETS-4（NS）, and ETS-4（NaF） were respectively synthesized using traced ETS-4 seeds, without seeds, and with fluoride ions. The as-synthesized samples were identified by X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. Adsorption isotherms and adsorption heats of nitrogen and methane on the prepared ETS-4 were also measured. The results showed that ETS-4 samples could be prepared using anatase in the absence of fluoride ions, with good purity, comparable physicochemical properties, and excellent adsorption properties.
基金This work was supported by the National Natural Science Foundation of China(20673124).
文摘Porous silicon carbide/carbon （SiC/C） microspherules were prepared by the controlled heating treatment of polymer and silica hybrid precursors over 1000℃ in Ar/H2 stream. The resultant SiC/C composite shows improved physical properties such as excellent mechanical strength, regular physical form, and high packing density. Such improvement overcomes the main inherent problems encountered when using activated carbons as absorbents without sacrificing porosity properties. N2 sorption analysis shows that the SiC/C composite has a BET surface area of 1793 m^2/g and a pore volume of 0.92 ml/g. Methane adsorption isotherm is determined by the conventional volumetric method at 25℃ and up to 7.0 MPa. On volumetric basis, the SiC/C composite microspherules show methane storage of 145 （V/V） at 3.5 MPa and 25℃. The combination of excellent physical properties and porosity properties in this SiC/C composite lends a great possibility to develop a competitive storage system for natural gas.
基金the FNRS(Fonds National de la Recherche Scientifique,Belgium)for a FRIA doctoral fellowship and then a"Chargéde Recherches"fellowshipThis work was realised in the frame of the Belgian Federal Government PAI-IUAP program(INANOMAT P6/17)The financial support from the University of Namur(FUNDP),"Aide institutionnelle aux collaborations internationales"is also acknowledged.
文摘Optoelectronic nanocomposites are a new class of materials, which exhibit very interesting and particular properties and attract a growing attention due to their potential applications in information storage and optoelectronic devices. Zinc oxide, ZnO, is one of the most interesting binary semiconductor （3.37 eV） with very important optical properties, which can be used in the fields such as short wavelength lasers, blue light emitting diodes, UV detectors, gas sensors, etc. This paper reviews the very recent progress in the prepa- ration of silica-based ZnO nanocomposites. After an introduction reviewing the theoretical background, the article will begin with a survey of the optical properties and the quantum size effect （QSE） of ZnO/SiO2 nanocomposites prepared by the inclusion of ZnO nanoclusters inside silica mesoporous materials. The second part will focus on one of the most interesting properties of ZnO/SiO2 nanocomposites, which is the random lasing effect after one- and two-photon excitation. The final part will deal with the introduction of ZnO nanoparticles inside microporous zeolites and the observation of QSE. For comparison, the photoluminescence （PL） and QSE properties of ZnS nanoparticles occluded in mesoporous media are also described. New potential applications will be discussed since short-wavelength devices are required by industry to design, for instance, new information storage supports and biolabelling devices.
基金supported by the National Natural Science Foundation of China(No.21901198)Qing-Yuan Yang acknowledges the Thousand Talents Programs of Shaanxi Province.
文摘Comprehensive Summary Carbon dioxide(CO_(2))capture is one of the most important aspects of reducing global warming.In terms of CO_(2)capture,metal-organic frameworks(MOFs)have several advantages.However,it isn't easy to shape MOFs while maintaining their performance.Herein,we describe the development of a pellet-shaped ultramicroporous MOF,Ni(3-ain)2(3-ain=3-aminoinoisonicotinic acid),that is capable of selectively adsorbing CO_(2).Polyvinyl butyral(PVB)is used as a binder during the production of Ni(3-ain)2 MOF pellets.The adequately shaped material can maintain its crystallinity and exhibit a high CO_(2)adsorption capacity(3.73 mmol·g^(-1))at ambient conditions,which is significantly greater than those obtained for N_(2)(0.63 mmol·g^(-1))and CO(0.90 mmol·g^(-1)).Consequently,this material displays high IAST selectivities for CO_(2)/N_(2)(26.3,15/85,V/V)and CO_(2)/CO(19.2,1/99,V/V).According to the theoretical calculations,Ni(3-ain)2 preferentially adsorbs CO_(2)molecules over N_(2)molecules and CO molecules.The results of experiments on dynamic breakthrough have demonstrated that Ni(3-ain)2 pellets are capable of effectively separating CO_(2)/N_(2)or CO_(2)/CO mixtures under conditions of dynamic flow.Furthermore,the structured MOF materials can be synthesized in one step at kilogram scale.This work provides an avenue for the shaping of MOFs for potential industrial applications in the future.
基金supported by the National Research Foundation (NRF),Prime Minister’s Office,Singapore under its NRF Fellowship (NRF2009NRF-RF001-015)Campus for Research Excellence and Technological Enterprise (CREATE)Programme-Singapore Peking University Research Centre for a Sustainable Low-Carbon Futurethe NTU-A*Star Centre of Excellence for Silicon Technologies (A*Star SERC No.:1123510003).
文摘An imine-based nitrogen-rich covalent-organic framework(COF)was successfully synthesized using two tri-angular building units under solvothermal reaction condition.The gas adsorption properties of the obtained micro-porous nitrogen-rich COF were investigated.The results indicated that the activated COF material presented good up take capabilities of CO_(2) and CH_(4) at 61.2 and 43.4 cm^(3)·g^(−1)at 1 atm and 273 K,respectively,showing its applica-tion potential in selective gas capture and separation.
基金financially supported by the Key Project of the National Natural Science Foundation of China(Grant No.U21A2058)the Natural Science Funds of Hubei Province for Distinguished Young Scholars(Grant No.2020CFA088).
文摘Using microporous raw materials to prepare reticulated ceramic filters for molten steel purification is a novel strategy to enhance the purification efficiency.Steel immersion tests were conducted on two batches of periclase-spinel ceramic filters prepared from microporous magnesia raw material and α-Al_(2)O_(3) micro-powder,and their performance was compared with pure MgO filter.The results showed that the periclase-spinel filters exhibited superior performance.This was attributed to two factors:first,the spinel microparticles within the filter skeletons had a greater advantage over magnesia microparticles in adsorbing spinel inclusions with similar chemical composition from the steel;second,the in-situ generated spinel increased the surface roughness of the skeletons and raised the contact angle between the filter and molten steel,thereby improving purification efficiency.When theα-Al_(2)O_(3) micro-powder content was 15 wt.%,the filter demonstrated excellent purification efficiency,the Al_(2)O_(3) and MgAl_(2)O_(4) inclusions in the molten steel were effectively removed,with an overall inclusion removal efficiency of 83.1%,and the total oxygen content in the steel decreased from 37.5×10^(−6) to 5.7×10^(−6),with a reduction of 84.8%.
基金financially supported by the National Natural Science Foundation of China(Nos.22150004,22431006,22301102,22475083 and 22271120)Guangdong Major Project of Basic and Applied Research(No.2019B030302009)+2 种基金Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515010952 and 2024A1515012434)China Postdoctoral Science Foundation(Nos.BX20220132 and 2023M741375)the Fundamental Research Funds for the Central Universities(No.21624213).
文摘CONSPECTUS:The separation and purification of hydrocarbons are crucially important processes in the petrochemical industry,as they are essential for producing high-quality chemicals and fuels.However,traditional thermal-driven separation practices,such as cryogenic distillation,are notoriously energy-intensive,accounting for a notable portion of the energy consumption in industrial operations.This has spurred the exploration and development of low-energy and sustainable alternative separation technologies,among which adsorption/desorption-based separation with porous materials has gained significant attention.Metal−organic frameworks(MOFs)are emerging as ideal porous materials for hydrocarbon separation due to their exceptional porosity and structural tunability.This Account delves into the latest advancements in microporous MOFs for hydrocarbon separation,categorizing them based on their pore structures:single array,tandem array,and orthogonal array.Single-array MOFs feature uniformly arranged channel-like pores along the axial direction,facilitating the incorporation of binding sites on the pore surfaces.One notable functional group used in these applications is open metal sites(OMSs),which can engage in strong metal-πinteractions with unsaturated hydrocarbons such as acetylene.For example,JNU-1 demonstrates increased binding energy with the increasing pressure of acetylene due to the induce-fit effect,where framework contraction behavior is triggered by its OMSs.JNU-4 offers two binding sites per metal center for acetylene molecules,greatly improving the adsorption capacity.On the other hand,introducing low-polarity groups,as seen in JNU-6-CH3,can effectively enhance the separation performance in favor of alkanes while maintaining structural integrity under humid conditions.Another methyl group-modified MOF,JNU-5-CH3,exhibits an acetylene-triggered gateopening effect due to the multiple supramolecular interactions with acetylene.Tandem-array MOFs provide enhanced selectivity and adsorption capacity through the interconnection of spacious cavities with narrow apertures.For instance,JNU-2 with pore-channel interconnected structure exhibits improved separation efficiency for C2H6/C2H4 and hexane isomers.The slim channels connecting the large cavities act as screening sites for matching-sized molecules to pass through,while the large cavities function as storage sites for large adsorption capacity.Orthogonal-array MOFs,like JNU-3a,feature one-dimensional(1D)channels that enable rapid diffusion,complemented by molecular pockets on both sides that facilitate selective recognition.The dynamic“gourd-shaped”opening of the pocket demonstrates notable adaptability when interacting with different hydrocarbons,allowing for sieving-like behavior in the separation of propylene/propane,as well as efficient separation of ethylene from its mixtures with alkynes of various sizes.Overall,the designability and tunability of MOF pore structures make them promising candidates for effectively discriminating targeted molecules from multicomponent mixtures,offering energy-efficient solutions for challenging industrial separations.
基金supported by National Key R&D Program of China(2022YFB3806800)National Natural Science Foundation of China(22278287,22278288,22090062).
文摘Separating propylene(C_(3)H_(6))from propane(C_(3)H_(8))is a complex procedure in the petrochemical sector due to the comparable characteristics of the two gases.Herein,we reported the self-assembly phenomenon of NbOFFIVE-1-Ni(KAUST-7)crystals under different synthetic routes.The material features a decreased framework strain energy compared to original KAUST-7 and exhibits completely different adsorption performance,achieving the efficient separation of C_(3)H_(6)/C_(3)H_(8) by synergetic effect of equilibrium and kinetics.The C.Headsorptiocapacitywas as highas 46.2cm^(3)·g^(-1)(298k.1bar),increasing by 3%compared to theoriginalmaterial.The difusion rates of C_(3)H_(6) were faster than C_(3)H_(8) as confirmed by time dependent kinetic adsorption profiles.It concurrently combines an excellent C_(3)H_(6)/C_(3)H_(8) uptake ratio of 3.1 and kinetic selectivity(96.5)for C_(3)H_(6)/C_(3)H_(8) separation with an equilibrium-kinetic combined selectivity of 42.5.Meanwhile,it can be regenerated easily due to moderate isosteric heat of adsorption(28.7 kJ·mol^(-1)).Breakthrough experiment for C_(3)H_(6)/C_(3)H_(8) gas mixture was conducted and confirmed the high-purity recovery of CsHs over CgHg.Moreover,it exhibited excellent water and moisture stability and can be easily synthesized through stirring at room temperature,which confers them with great potentialforindustrialapplication.
文摘The zeolitic imidazolate framework-8 （ZIF-8） was successfully synthesized using ionic liquids as struc- ture-directing agent under microwave irradiation. Ionic liquids are green solvents with low vapour pressure and good thermal stability. They are appropriate templates for microporous materials and ideal microwave absorbers. The microwave-assisted ionothermal synthesis applied in this paper was expected to be a promising method for the preparation of microporous materials. Results showed that the as-synthesized samples （300---500 nm in diameter） could be synthesized in a short time （60 min） and possessed regular morphology, stable structure and high thermal stability （up to 720 ~C in argon atmosphere）. Nitrogen adsorption-desorption test illustrated that samples produced by microwave heating had a higher surface area. Carbon dioxide adsorption test indicated that the samples synthe- sized by microwave heating had better carbon dioxide adsorption ability than those by conventional heating.
基金supported bythe National Natural Science Foundation of China(Nos.22025504,21621001,21390394,and 22105082)"111"project(Nos.BP0719036 and B17020)+1 种基金China Postdoctoral Science Foundation(Nos.22020TQ0118 and 2020M681034)the program for JLU Science and Technology Innovative Research Team.V.V.,S.Q.and Q.F.acknowledge funding from the French-Sino International Laboratory(LIA)"Zeolites"。
文摘Three-dimensional(3D)covalent organic frameworks(COFs)are crystalline porous polymers with potential in numerous high-tech applications,but the linkages involved in their synthesis are still rather limited.Herein,we report novel 3D sp^(2) carbon-linked COFs fabricated by the formation reaction of C=C bonds and their application in fluorescence imaging.These new COFs,namely JUC-580 and JUC-581,show high stability and excellent light-emitting properties in solid state and dispersed in various solvents.Furthermore,we investigate the potential application of JUC-581 as a drug carrier combined with fluorescence imaging.These results indicate that 3D sp^(2) carbon-linked COFs are not only potential drug-loaded and sustained release materials but also promising cell fluorescent stains.This study thus expands the structural categories of 3D COFs based on different linkages,and promotes their prospective applications for biomedicine and fluorescent materials.
基金supported by the NSFC(Nos.21731007,21821003,22090061,and 22071272)the Guangdong Pearl River Talents Program(No.2017BT01C161)the Guangzhou Science and Technology Bureau(No.202102020296).
文摘Solvothermal reactions of 3,6-di(pyridin-4-yl)-9H-carbazole(dpc)with Cu(ll)yielded crystals of two new coordination complexes,namely[Cu(CH_(3)COO)_(2)(dpc)(H_(2)O)_(2)]n-xvip(1)and[Cu_(13)(HCOO)_(16)(dpc)16(H_(2)O)6](HCOO)10-vip(2),in which CH_(3)COO_and HCOO-were generated from the hydrolysis of the solvents A/zAZ-dimethylacetamide(DMA)and A/zA/-dimethylformamide(DMF),respectively.Single-crystal X-ray diffraction showed that 1 possesses simple wavy coordination chains,while 2 possesses large molecular bowls/sieves with outer and inner effective sizes of 30.2 × 30.2 × 25.5 A^(3) and 15.0 × 15.0 × 18.6 A^(3),respectively,which consists of 4 linear Cu_(3)(HCOO)_(4)(H_(2)O)clusters and 12 dpc ligands as the square-shaped wall and a claw-like Cu(dpc)_(4) fragment as the bottle.vip-free 2 can adsorb considerable amounts of CO_(2)/H_(2)O and CH_(3)OH but completely exclude C2H4 and C3H6z which shows a potential application for olefin drying.
基金We thank financial support from National Natural Science Foundation of China(52061135103 and 52173296)Structure characterizations were supported by Instrumental Analysis and Research Center of Sun Yat-sen University.
文摘The dilemma for the synthesis of covalent organic frameworks(COFs)is crystallinity and stability.Herein,we present the synthesis of a single-crystalline amide-linked COF,and demonstrate its excellent chemical as well as thermal stabilities.This study will inspire the synthesis of a wide spectrum of highly crystalline and stable COFs,promote their structure-property investigations and boost their applications in selective gas adsorption,storage and separation.
基金This study was supported byÅForsk research grant and Anhui Provincial Natural Science Foundation(No.2108085QB72)。
文摘Utilizing solar energy for sorbent regeneration during the CO_(2)swing adsorption process could potentially reduce CO_(2)capture costs.This study describes a new technique—solar thermal swing adsorption(STSA)for CO_(2)capture based on application of intermittent illumination onto porous carbon monolith(PCM)sorbents during the CO_(2)capture process.This allows CO_(2)to be selectively adsorbed on the sorbents during the light-off periods and thereafter released during the light-on periods due to the solar thermal effect.The freestanding and mechanically strong PCMs have rich ultramicropores with narrow pore size distributions,displaying relatively high CO_(2)adsorption capacity and high CO_(2)/N_(2) selectivity.Given the high CO_(2)capture performance,high solar thermal conversion efficiency,and high thermal conductivity,the PCM sorbents could achieve high CO_(2)capture rate of up to 0.226 kg·kgcarbon^(-1)·h^(-1)from a gas mixture of 20 vol.%CO_(2)/80 vol.%N_(2) under STSA conditions with a light intensity of 1000 W·m^(-2).In addition,the combination of STSA with the conventional vacuum swing adsorption technique further increases the CO_(2)working capacity.
