The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and...The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and[Mg_(2)(L)_(2)(DMSO)_(3)(H_(2)O)](2)with a 2D(4,4)-net structure.Interestingly,the two compounds exhibit distinct luminescent responses to external mechanical stimuli.1 exhibited exceptional resistance mechanical chromic luminescence(RMCL),which can be attributed to the predominant hydrogen bonds and the presence of high-boiling-point solvent molecules within its structure.2 had a reversible MCL property,which can be attributed to the dominantπ-πweak interactions,coupled with the reversible destruction/restoration of its crystallinity under grinding/fumigation.CCDC:2410963,1;2410964,2.展开更多
(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under...(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.展开更多
Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structu...Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structures.These explosives exhibit significant advantages over traditional compounds,including higher density,greater heats of detonation,improved mechanical hardness,and excellent thermal stability.To effectively evaluate their detonation performance,it is crucial to have a reliable method for predicting detonation heat,velocity,and pressure.This study leverages experimental data and outputs from the leading commercial computer code to identify suitable decomposition pathways for different metal oxides,facilitating straightforward calculations for the detonation performance of alkali metal salts,and metal coordination compounds,along with EMOFs.The new model enhances predictive reliability for detonation velocities,aligning more closely with experimental results,as evi-denced by a root mean square error(RMSE)of 0.68 km/s compared to 1.12 km/s for existing methods.Furthermore,it accommodates a broader range of compounds,including those containing Sr,Cd,and Ag,and provides predictions for EMOFs that are more consistent with computer code outputs than previous predictive models.展开更多
Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 ...Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 in complex environmental samples.Here,solid-state nanochannels,modified with metal-organic frameworks(MOF)and specific aptamers,were engineered for highly sensitive detection of strontium ion(Sr^(2+)).The synergistic effect between the reduced effective diameter of the nanochannels due to MOF and the specific binding of Sr^(2+) by aptamers amplifies the difference in ionic current signals,enhancing detection sensitivity significantly.The MOF-modified nanochannels exhibit highly sensitive detection of Sr^(2+),with a limit of detection(LOD)being 0.03 nmol·L^(-1),whereas the LOD for anodized aluminum oxide(AAO)without the modified MOF nanosheets is only 1000 nmol·L^(-1).These findings indicate that the LOD of Sr^(2+) detected by the MOF-modified nanochannels is approximately 33,000 times higher than that by the nanochannels without MOF modification.Additionally,the highly reliable detection of Sr^(2+) in various water samples was achieved,with a recovery rate ranging from 94.00%to 118.70%.This study provides valuable insights into the rapidly advancing field of advanced nanochannel-based sensors and their diverse applications for analyzing complex samples,including environmental contaminant detection,food analysis,medical diagnostics,and more.展开更多
The realization of real-time thermal feedback for monitoring photothermal therapy(PTT)under near-infrared(NIR)light irradiation is of great interest and challenge for antitumor therapy.Herein,by assembling highly effi...The realization of real-time thermal feedback for monitoring photothermal therapy(PTT)under near-infrared(NIR)light irradiation is of great interest and challenge for antitumor therapy.Herein,by assembling highly efficient photothermal conversion gold nanorods and a temperature-responsive probe((E)-4-(4-(diethylamino)styryl)-1-methylpyridin-1-ium,PyS)within MOF-199,an intelligent nanoplatform(AMPP)was fabricated for simultaneous chemodynamic therapy and NIR light-induced temperature-feedback PTT.The fluorescence intensity and temperature of the PyS probe are linearly related due to the restriction of the rotation of the characteristic monomethine bridge.Moreover,the copper ions resulting from the degradation of MOF-199 in an acidic microenvironment can convert H_(2)O_(2)into•OH,resulting in tumor ablation through a Fenton-like reaction,and this process can be accelerated by increasing the temperature.This study establishes a feasible platform for fabricating highly sensitive temperature sensors for efficient temperature-feedback PTT.展开更多
Metal-organic frameworks(MOFs)represent a class of multifunctional hybrid materials distinguished by their tunable structural architectures,adjustable pore dimensions,and tailorable surface chemical functionalities,wh...Metal-organic frameworks(MOFs)represent a class of multifunctional hybrid materials distinguished by their tunable structural architectures,adjustable pore dimensions,and tailorable surface chemical functionalities,which underpin their broad applicability across diverse domains.Within the cosmetics industry,MOFs exhibit significant application potential owing to their high thermal and chemical stability,substantial loading capacity,low biological toxicity,favorable luminescent characteristics,and robust catalytic activity,leading to their increasing deployment in various cosmetic-related applications.This article systematically outlines the structural features and functional properties of MOFs,emphasizing their suitability for integration into cosmetic systems.Furthermore,it provides a comprehensive review of recent advances in the utilization of MOFs in cosmetics,encompassing the detection of organic contaminants and metal ions,ultraviolet protection,encapsulation,and controlled release of volatile active ingredients,as well as targeted delivery of dermatological therapeutic agents.The structure-property-application relationships of MOFs are critically examined.Building upon the foundation of existing research,this study offers a comprehensive outlook on the future development of MOFs in the field of cosmetics.It presents several strategic perspectives,including an in-depth analysis of current application studies,the expansion of MOFs applications into additional cosmetic domains,the integration of multifunctional MOFs systems,the development of MOFs-based composite materials,and the scale-up of synthesis processes from laboratory-scale research to industrial production.It is expected that the present piece of paper can contribute valuable guidance for further exploration and practical implementation in this emerging field of cosmetics.展开更多
A cobalt-based metal-organic framework[Co_(3)(L)_(2)(1,4-bib)_(4)]·4H_(2)O(Co-MOF)was prepared using 5-[(4-carboxyphenoxy)methyl]isophthalic acid(H_(3)L)and 1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib)as ligands.The...A cobalt-based metal-organic framework[Co_(3)(L)_(2)(1,4-bib)_(4)]·4H_(2)O(Co-MOF)was prepared using 5-[(4-carboxyphenoxy)methyl]isophthalic acid(H_(3)L)and 1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib)as ligands.Then,an electrochemical sensor modified with Co-MOF on a glassy carbon electrode(Co-MOF@GCE)was constructed for detecting Cd^(2+)and Pb^(2+)in aqueous solutions.The sensor exhibited a linear range of 1.0-16.0µmol·L^(-1)with a detection limit(LOD)of 4.609 nmol·L^(-1)for Cd^(2+),and 0.5-10.0µmol·L^(-1)with an LOD of 1.307 nmol·L^(-1)for Pb^(2+).Simultaneous detection of both ions within 0.5-7.0µmol·L^(-1)achieved LOD values of 0.47 nmol·L^(-1)(Cd^(2+))and 0.008 nmol·L^(-1)(Pb^(2+)),respectively.Analysis of real water samples(tap water,mineral water,and river water)yielded recoveries of 95%-105%,validating practical applicability.Density functional theory(DFT)calculations reveal that synergistic interactions between cobalt centers and N/O atoms enhance adsorption and electron-transfer efficiency.CCDC:2160744.展开更多
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano...Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.展开更多
The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively red...The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.展开更多
There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An importa...There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An important way to improve the performance of lithium battery is to improve the separator.Here,three novel separators combined with metal-organic framework materials(MOFs)and carbon materials were prepared by using the in situ growth method and the adsorption combination method simultaneously.The result showed that compared with the polypropylene separator,the porosity and electrolyte wettability were significantly improved in view of these novel polypropylene separators combined with MOFs and carbon materials.Meanwhile,the electrochemical performance of lithium battery equipped with the polypropylene separator combined with MOFs materials and carbon materials was also improved.The result showed that lithium batteries equipped with polypropylene separator combined with MOFs and carbon materials had higher capacity in the first charge and discharge cycle and better electrochemical kinetic reaction processes.展开更多
Preparing multifunctional coatings with both anti-corrosion and anti-biofouling properties is crucial.Copper has been in the spotlight as an effective biocide,especially in the recent past concerning its impact on cau...Preparing multifunctional coatings with both anti-corrosion and anti-biofouling properties is crucial.Copper has been in the spotlight as an effective biocide,especially in the recent past concerning its impact on causing environmental hazards.Reducing the amount used and increasing its efficiency have become the focus of researchers.The hybridization of titanium dioxide nanoparticles(NPs)with copper metal-organic frameworks(MOFs)can significantly improve antimicrobial performance due to its photocatalytic properties.Composites(TiO_(2)-Cu-BTC)of titanium dioxide nanoparticles and copper 1,3,5-benzenetricarboxylate acid(Cu-BTC),obtained by three up-sampling methods,namely hydrothermal,mechanical stirring,and in-situ growth,were doped into epoxy resin(TiO_(2)-Cu-BTC/EP)to enhance its anticorrosion and antifouling properties.The loaded forms were determined by field emission scanning electron microscopy and confirmed using Fourier infrared spectroscopy and X-ray diffraction spectroscopy.The lethality of the composite coating against Escherichia coli(E.coli)increased by 12%after 3 h of exposure to light,and the impedance value increased by 1×1010Ω.The efficiency of the coating was greatly improved.展开更多
Efficiently converting CO_(2)and H_(2)O into value-added chemicals using solar energy is a viable approach to address global warming and the energy crisis.However,achieving artificial photocatalytic CO_(2)reduction us...Efficiently converting CO_(2)and H_(2)O into value-added chemicals using solar energy is a viable approach to address global warming and the energy crisis.However,achieving artificial photocatalytic CO_(2)reduction using H_(2)O as the reductant poses challenges is due to the difficulty in efficient cooperation among multiple functional moieties.Metal-organic frameworks(MOFs)are promising candidates for overall CO_(2)photoreduction due to their large surface area,diverse active sites,and excellent tailorability.In this study,we designed a metal-organic framework photocatalyst,named PCN-224(Zn)-Bpy(Ru),by integrating photoactive Zn(Ⅱ)-porphyrin and Ru(Ⅱ)-bipyridyl moieties.In comparison,two isostructural MOFs just with either Zn(Ⅱ)-porphyrin or Ru(Ⅱ)-bipyridyl moiety,namely PCN-224-Bpy(Ru)and PCN-224(Zn)-Bpy were also synthesized.As a result,PCN-224(Zn)-Bpy(Ru)exhibited the highest photocatalytic conversion rate of CO_(2)to CO,with a production rate of 7.6μmol·g^(-1)·h^(-1)in a mixed solvent of CH_(3)CN and H_(2)O,without the need for co-catalysts,photosensitizers,or sacrificial agents.Mass spectrometer analysis detected the signals of^(13)CO(m/z=29),^(13)C^(18)O(m/z=31),^(16)O^(18)O(m/z=34),and^(18)O_(2)(m/z=36),confirming that CO_(2)and H_(2)O acted as the carbon and oxygen sources for CO and O_(2),respectively,thereby confirming the coupling of photocatalytic CO_(2)reduction with H_(2)O oxidation.In contrast,using PCN-224-Bpy(Ru)or PCN-224(Zn)-Bpy as catalysts under the same conditions resulted in significantly lower CO production rates of only 1.5 and 0μmol·g^(-1)·h^(-1),respectively.Mechanistic studies revealed that the lowest unoccupied molecular orbital(LUMO)potential of PCN-224(Zn)-Bpy(Ru)is more negative than the redox potentials of CO_(2)/CO,and the highest occupied molecular orbital(HOMO)potential is more positive than that of H_(2)O/O_(2),satisfying the thermodynamic requirements for overall photocatalytic CO_(2)reduction.In comparison,the HOMO potential of PCN-224(Zn)-Bpy without Ru(II)-bipyridyl moieties is less positive than that of H_(2)O/O_(2),indicating that the Ru(II)-bipyridyl moiety is thermodynamically necessary for CO_(2)reduction coupled with H_(2)O oxidation.Additionally,photoluminescence spectroscopy revealed that the fluorescence of PCN-224(Zn)-Bpy(Ru)was almost completely quenched,and a longer average photoluminescence lifetime compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru)was observed.These suggest a low recombination rate of photogenerated carriers in PCN-224(Zn)-Bpy(Ru),which also supported by the higher photocurrent observed in PCN-224(Zn)-Bpy(Ru)compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru).In summary,the integrated Zn(II)-porphyrin and Ru(II)-bipyridyl moieties in PCN-224(Zn)-Bpy(Ru)play important roles of a photosensitizer and CO_(2)reduction as well as H_(2)O oxidation sites,and their efficient cooperation optimizes the band structure,thereby facilitating the coupling of CO_(2)reduction with H_(2)O oxidation and resulting in highperformance artificial photocatalytic CO_(2)reduction.展开更多
CO_(2),as a greenhouse gas,has excessive emissions that lead to many environmental problems and is a rich and cheap C1 resource.Effective utilization and transformation of CO_(2)has become an important means of achiev...CO_(2),as a greenhouse gas,has excessive emissions that lead to many environmental problems and is a rich and cheap C1 resource.Effective utilization and transformation of CO_(2)has become an important means of achieving carbon neutrality.Oxazolidinones are important intermediates in pharmaceutical chemistry that can be synthesized by carboxylation cyclization of CO_(2)with propargyl amines or cycloaddition of CO_(2)with aziridines.Owing to CO_(2)’s high stability,these reactions typically require harsh conditions,such as high temperatures or pressures.It is desirable,but challenging,to find a catalyst that can catalyze these two types of reactions under relatively mild conditions.Metal-organic frameworks(MOFs)are an emerging class of heterogeneous catalysts that with great potential in the catalytic conversion of CO_(2)to value-added products because of their attractive features,such as abundant metal active sites,inherent porosity,and easy functionalities.Herein,a unique three-dimensional(3D)MOF,{(CH_(3)NH_(2)CH_(3))_(2)[Co_(3)(BCP)_(2)]·6H_(2)O·4DMF}n(1)(H_(4)BCP:5‐(2,6‐bis(4‐carboxyphenyl)pyridin‐4‐yl)isophthalic acid;DMF:N,N'‐dimethylformamide),was synthesized using carboxylic acid ligands and cobalt salts via a solvothermal method.According to structural analysis,[Co_(3)]clusters as secondary building units(SBU)are bridged by BCP4−ligands,forming an anion framework with flu topology,and dimethylamine cations act as counter ions in the pores.The framework has rectangular channels of approximately 0.4 nm×0.9 nm along the a-axis direction,exhibiting its porous property.Infrared spectroscopy(IR)and X-ray photoelectron spectroscopy(XPS)characterizations proved the coordination interaction between the carboxyl groups in the ligands and the metal ions.The powder X-Ray diffraction(PXRD)test further confirmed the phase purity of the synthesized samples.PXRD and thermogravimetry(TG)analyses indicated that 1 possessed good solvent and thermal stabilities.The catalytic experiments revealed that 1 could effectively catalyze CO_(2)with aziridines or propargyl amines to prepare oxazolidinones.In the cycloaddition of CO_(2)with aziridines,1 can facilitate the reaction under relatively mild conditions compared to other reported MOF-based catalysts.It shows excellent universality for substrates with various substitutions on the N atom or benzene ring.Investigation of the mechanism indicated that the coordination interaction of cobalt metal sites with the nitrogen atoms of aziridines can activate the substrates.For the carboxylative cyclization of CO_(2)with propargylic amines,this catalyst also has a broad substrate scope.Control experiments and nuclear magnetic resonance(NMR)tests suggest that Lewis acid metal sites are responsible for the high catalytic efficiency achieved by activating the alkyne groups.Moreover,1 showed good reusability in both reactions.Compound 1 represents a new catalyst that enables“two birds with one stone”in the catalytic synthesis of oxazolidinones using CO_(2).展开更多
Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power density.However,the ...Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power density.However,the low energy density and the lack of sustainable design strategies for the cathodes hinder the practical application of ZIHCs.Herein,we design the N and O co-doped porous carbon cathode by annealing metal-organic framework(ZIF-8).ZIF-8 retains the original dodecahedral structure with a high specific surface(2814.67 m^(2)/g)and I_(G)/I_(D) ratio of 1.0 during carbonization and achieves self-doping of N and O heteroatoms.Abundant defect sites are introduced into the porous carbon to provide additional active sites for ion adsorption after the activation of carbonized ZIF-8 by KOH treatment.The ZIHCs assembled with modified ZIF-8 as the cathode and commercial zinc foil as the anode show an energy density of 125 W∙h/kg and a power density of 79 W/kg.In addition,this ZIHCs device achieves capacity retention of 77.8%after 9000 electrochemical cycles,which is attributed to the diverse pore structure and plentiful defect sites of ZIF-8-800(KOH).The proposed strategy may be useful in developing high-performance metal-ion hybrid capacitors for large-scale energy storage.展开更多
Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)...Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)O dis-solved in N,N-dimethylformamide,and were converted into Fe-Co embedded in N-doped porous carbon polyhedra by pyrolysis in a nitrogen atmosphere.During pyrolysis,the or-ganic ligands transformed into N-doped porous carbon which improved their structural stability and also their electrical contact with other materials.The Fe and Co are tightly bound together because of their encapsulation by the carbon nitride and are well dispersed in the carbon matrix,and improve the material’s conductivity and stability and provide additional capacity.When used as the anode for lithium-ion batteries,the material gives an initial capacity of up to 2230.7 mAh g^(-1)and a reversible capa-city of 1146.3 mAh g^(-1)is retained after 500 cycles at a current density of 0.5 A g^(-1),making it an excellent candidate for this purpose.展开更多
The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal ve...The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal vehicle dynamics model was built by taking the information delay into consideration, and three typical information frameworks, i.e., leader-predecessor framework (LPF), multiple-predecessors framework (MPF) and predecessor-successor framework (PSF), were defined and their related spacing error dynamics models in frequency domain were proposed. The string stability of platoon of automated vehicles was analyzed for the LPF, MPF and PSF, respectively. Meanwhile, the related sufficient string stable conditions were also obtained. The results demonstrate that the string stability can be guaranteed tbr the LPF and PSF with considering the information delay, but the ranges of the control gains of the control laws are smaller than those without considering the information delay. For the MPF, the "weak" string stability, which can be guaranteed without considering the information delay, cannot be obtained with considering the information delay. The comparative simulations further demonstrate that the LPF shows better string stability, but the PSF shows better string scalable performance.展开更多
A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIB...A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIBs).The effect of reaction temperature and time on morphologies of Sb2O3 was studied.The results from SEM and TEM demonstrate that the tremella-like Sb2O3 architecture are composed of numerous nanosheets with high specific surface area.When the tremella-like Sb2O3 was used as LIBs anode,the discharge and charge capacities can achieve 724 and 446 mA·h/g in the first cycle,respectively.Moreover,the electrode retains an impressive high capacity of 275 mA·h/g even after 50 cycles at 20 mA/g,indicating that the material is extremely promising for application in LIBs.展开更多
Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as...Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.展开更多
Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imida...Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.展开更多
Energetic metal-organic complexes have been involved in nanothermites as novel oxidants.However,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity ...Energetic metal-organic complexes have been involved in nanothermites as novel oxidants.However,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still limited.In this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.展开更多
文摘The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and[Mg_(2)(L)_(2)(DMSO)_(3)(H_(2)O)](2)with a 2D(4,4)-net structure.Interestingly,the two compounds exhibit distinct luminescent responses to external mechanical stimuli.1 exhibited exceptional resistance mechanical chromic luminescence(RMCL),which can be attributed to the predominant hydrogen bonds and the presence of high-boiling-point solvent molecules within its structure.2 had a reversible MCL property,which can be attributed to the dominantπ-πweak interactions,coupled with the reversible destruction/restoration of its crystallinity under grinding/fumigation.CCDC:2410963,1;2410964,2.
文摘(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.
基金the research committee at Malek Ashtar University of Technology (MUT) for their invaluable support of this project
文摘Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structures.These explosives exhibit significant advantages over traditional compounds,including higher density,greater heats of detonation,improved mechanical hardness,and excellent thermal stability.To effectively evaluate their detonation performance,it is crucial to have a reliable method for predicting detonation heat,velocity,and pressure.This study leverages experimental data and outputs from the leading commercial computer code to identify suitable decomposition pathways for different metal oxides,facilitating straightforward calculations for the detonation performance of alkali metal salts,and metal coordination compounds,along with EMOFs.The new model enhances predictive reliability for detonation velocities,aligning more closely with experimental results,as evi-denced by a root mean square error(RMSE)of 0.68 km/s compared to 1.12 km/s for existing methods.Furthermore,it accommodates a broader range of compounds,including those containing Sr,Cd,and Ag,and provides predictions for EMOFs that are more consistent with computer code outputs than previous predictive models.
基金supported by the National Natural Science Foundation of China(No.22090050,No.22090052,No.22176180)National Basic Research Program of China(No.2021YFA1200400)+1 种基金the Natural Science Foundation of Hubei Province(No.2024AFA001)Shenzhen Science and Technology Program(No.JCYJ20220530162406014)。
文摘Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 in complex environmental samples.Here,solid-state nanochannels,modified with metal-organic frameworks(MOF)and specific aptamers,were engineered for highly sensitive detection of strontium ion(Sr^(2+)).The synergistic effect between the reduced effective diameter of the nanochannels due to MOF and the specific binding of Sr^(2+) by aptamers amplifies the difference in ionic current signals,enhancing detection sensitivity significantly.The MOF-modified nanochannels exhibit highly sensitive detection of Sr^(2+),with a limit of detection(LOD)being 0.03 nmol·L^(-1),whereas the LOD for anodized aluminum oxide(AAO)without the modified MOF nanosheets is only 1000 nmol·L^(-1).These findings indicate that the LOD of Sr^(2+) detected by the MOF-modified nanochannels is approximately 33,000 times higher than that by the nanochannels without MOF modification.Additionally,the highly reliable detection of Sr^(2+) in various water samples was achieved,with a recovery rate ranging from 94.00%to 118.70%.This study provides valuable insights into the rapidly advancing field of advanced nanochannel-based sensors and their diverse applications for analyzing complex samples,including environmental contaminant detection,food analysis,medical diagnostics,and more.
基金supported by the National Natural Science Foundation of China(22171001,22305001,51972001,52372073)the Natural Science Foundation of Anhui Province of China(2108085MB49).
文摘The realization of real-time thermal feedback for monitoring photothermal therapy(PTT)under near-infrared(NIR)light irradiation is of great interest and challenge for antitumor therapy.Herein,by assembling highly efficient photothermal conversion gold nanorods and a temperature-responsive probe((E)-4-(4-(diethylamino)styryl)-1-methylpyridin-1-ium,PyS)within MOF-199,an intelligent nanoplatform(AMPP)was fabricated for simultaneous chemodynamic therapy and NIR light-induced temperature-feedback PTT.The fluorescence intensity and temperature of the PyS probe are linearly related due to the restriction of the rotation of the characteristic monomethine bridge.Moreover,the copper ions resulting from the degradation of MOF-199 in an acidic microenvironment can convert H_(2)O_(2)into•OH,resulting in tumor ablation through a Fenton-like reaction,and this process can be accelerated by increasing the temperature.This study establishes a feasible platform for fabricating highly sensitive temperature sensors for efficient temperature-feedback PTT.
文摘Metal-organic frameworks(MOFs)represent a class of multifunctional hybrid materials distinguished by their tunable structural architectures,adjustable pore dimensions,and tailorable surface chemical functionalities,which underpin their broad applicability across diverse domains.Within the cosmetics industry,MOFs exhibit significant application potential owing to their high thermal and chemical stability,substantial loading capacity,low biological toxicity,favorable luminescent characteristics,and robust catalytic activity,leading to their increasing deployment in various cosmetic-related applications.This article systematically outlines the structural features and functional properties of MOFs,emphasizing their suitability for integration into cosmetic systems.Furthermore,it provides a comprehensive review of recent advances in the utilization of MOFs in cosmetics,encompassing the detection of organic contaminants and metal ions,ultraviolet protection,encapsulation,and controlled release of volatile active ingredients,as well as targeted delivery of dermatological therapeutic agents.The structure-property-application relationships of MOFs are critically examined.Building upon the foundation of existing research,this study offers a comprehensive outlook on the future development of MOFs in the field of cosmetics.It presents several strategic perspectives,including an in-depth analysis of current application studies,the expansion of MOFs applications into additional cosmetic domains,the integration of multifunctional MOFs systems,the development of MOFs-based composite materials,and the scale-up of synthesis processes from laboratory-scale research to industrial production.It is expected that the present piece of paper can contribute valuable guidance for further exploration and practical implementation in this emerging field of cosmetics.
文摘A cobalt-based metal-organic framework[Co_(3)(L)_(2)(1,4-bib)_(4)]·4H_(2)O(Co-MOF)was prepared using 5-[(4-carboxyphenoxy)methyl]isophthalic acid(H_(3)L)and 1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib)as ligands.Then,an electrochemical sensor modified with Co-MOF on a glassy carbon electrode(Co-MOF@GCE)was constructed for detecting Cd^(2+)and Pb^(2+)in aqueous solutions.The sensor exhibited a linear range of 1.0-16.0µmol·L^(-1)with a detection limit(LOD)of 4.609 nmol·L^(-1)for Cd^(2+),and 0.5-10.0µmol·L^(-1)with an LOD of 1.307 nmol·L^(-1)for Pb^(2+).Simultaneous detection of both ions within 0.5-7.0µmol·L^(-1)achieved LOD values of 0.47 nmol·L^(-1)(Cd^(2+))and 0.008 nmol·L^(-1)(Pb^(2+)),respectively.Analysis of real water samples(tap water,mineral water,and river water)yielded recoveries of 95%-105%,validating practical applicability.Density functional theory(DFT)calculations reveal that synergistic interactions between cobalt centers and N/O atoms enhance adsorption and electron-transfer efficiency.CCDC:2160744.
文摘Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.
文摘The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.
基金2023 undergraduate Innovation and Entrepreneurship Project of Yichun University(S202310417015)。
文摘There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An important way to improve the performance of lithium battery is to improve the separator.Here,three novel separators combined with metal-organic framework materials(MOFs)and carbon materials were prepared by using the in situ growth method and the adsorption combination method simultaneously.The result showed that compared with the polypropylene separator,the porosity and electrolyte wettability were significantly improved in view of these novel polypropylene separators combined with MOFs and carbon materials.Meanwhile,the electrochemical performance of lithium battery equipped with the polypropylene separator combined with MOFs materials and carbon materials was also improved.The result showed that lithium batteries equipped with polypropylene separator combined with MOFs and carbon materials had higher capacity in the first charge and discharge cycle and better electrochemical kinetic reaction processes.
基金Project(52073311) supported by the National Natural Science Foundation of ChinaProject(2023A0505010011) supported by the Guangdong-Hong Kong-Macao Joint Innovation Field Research Foundation,ChinaProject(2021A1515012281) supported by the Guangdong Basic and Applied Basic Research Foundation,China。
文摘Preparing multifunctional coatings with both anti-corrosion and anti-biofouling properties is crucial.Copper has been in the spotlight as an effective biocide,especially in the recent past concerning its impact on causing environmental hazards.Reducing the amount used and increasing its efficiency have become the focus of researchers.The hybridization of titanium dioxide nanoparticles(NPs)with copper metal-organic frameworks(MOFs)can significantly improve antimicrobial performance due to its photocatalytic properties.Composites(TiO_(2)-Cu-BTC)of titanium dioxide nanoparticles and copper 1,3,5-benzenetricarboxylate acid(Cu-BTC),obtained by three up-sampling methods,namely hydrothermal,mechanical stirring,and in-situ growth,were doped into epoxy resin(TiO_(2)-Cu-BTC/EP)to enhance its anticorrosion and antifouling properties.The loaded forms were determined by field emission scanning electron microscopy and confirmed using Fourier infrared spectroscopy and X-ray diffraction spectroscopy.The lethality of the composite coating against Escherichia coli(E.coli)increased by 12%after 3 h of exposure to light,and the impedance value increased by 1×1010Ω.The efficiency of the coating was greatly improved.
文摘Efficiently converting CO_(2)and H_(2)O into value-added chemicals using solar energy is a viable approach to address global warming and the energy crisis.However,achieving artificial photocatalytic CO_(2)reduction using H_(2)O as the reductant poses challenges is due to the difficulty in efficient cooperation among multiple functional moieties.Metal-organic frameworks(MOFs)are promising candidates for overall CO_(2)photoreduction due to their large surface area,diverse active sites,and excellent tailorability.In this study,we designed a metal-organic framework photocatalyst,named PCN-224(Zn)-Bpy(Ru),by integrating photoactive Zn(Ⅱ)-porphyrin and Ru(Ⅱ)-bipyridyl moieties.In comparison,two isostructural MOFs just with either Zn(Ⅱ)-porphyrin or Ru(Ⅱ)-bipyridyl moiety,namely PCN-224-Bpy(Ru)and PCN-224(Zn)-Bpy were also synthesized.As a result,PCN-224(Zn)-Bpy(Ru)exhibited the highest photocatalytic conversion rate of CO_(2)to CO,with a production rate of 7.6μmol·g^(-1)·h^(-1)in a mixed solvent of CH_(3)CN and H_(2)O,without the need for co-catalysts,photosensitizers,or sacrificial agents.Mass spectrometer analysis detected the signals of^(13)CO(m/z=29),^(13)C^(18)O(m/z=31),^(16)O^(18)O(m/z=34),and^(18)O_(2)(m/z=36),confirming that CO_(2)and H_(2)O acted as the carbon and oxygen sources for CO and O_(2),respectively,thereby confirming the coupling of photocatalytic CO_(2)reduction with H_(2)O oxidation.In contrast,using PCN-224-Bpy(Ru)or PCN-224(Zn)-Bpy as catalysts under the same conditions resulted in significantly lower CO production rates of only 1.5 and 0μmol·g^(-1)·h^(-1),respectively.Mechanistic studies revealed that the lowest unoccupied molecular orbital(LUMO)potential of PCN-224(Zn)-Bpy(Ru)is more negative than the redox potentials of CO_(2)/CO,and the highest occupied molecular orbital(HOMO)potential is more positive than that of H_(2)O/O_(2),satisfying the thermodynamic requirements for overall photocatalytic CO_(2)reduction.In comparison,the HOMO potential of PCN-224(Zn)-Bpy without Ru(II)-bipyridyl moieties is less positive than that of H_(2)O/O_(2),indicating that the Ru(II)-bipyridyl moiety is thermodynamically necessary for CO_(2)reduction coupled with H_(2)O oxidation.Additionally,photoluminescence spectroscopy revealed that the fluorescence of PCN-224(Zn)-Bpy(Ru)was almost completely quenched,and a longer average photoluminescence lifetime compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru)was observed.These suggest a low recombination rate of photogenerated carriers in PCN-224(Zn)-Bpy(Ru),which also supported by the higher photocurrent observed in PCN-224(Zn)-Bpy(Ru)compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru).In summary,the integrated Zn(II)-porphyrin and Ru(II)-bipyridyl moieties in PCN-224(Zn)-Bpy(Ru)play important roles of a photosensitizer and CO_(2)reduction as well as H_(2)O oxidation sites,and their efficient cooperation optimizes the band structure,thereby facilitating the coupling of CO_(2)reduction with H_(2)O oxidation and resulting in highperformance artificial photocatalytic CO_(2)reduction.
文摘CO_(2),as a greenhouse gas,has excessive emissions that lead to many environmental problems and is a rich and cheap C1 resource.Effective utilization and transformation of CO_(2)has become an important means of achieving carbon neutrality.Oxazolidinones are important intermediates in pharmaceutical chemistry that can be synthesized by carboxylation cyclization of CO_(2)with propargyl amines or cycloaddition of CO_(2)with aziridines.Owing to CO_(2)’s high stability,these reactions typically require harsh conditions,such as high temperatures or pressures.It is desirable,but challenging,to find a catalyst that can catalyze these two types of reactions under relatively mild conditions.Metal-organic frameworks(MOFs)are an emerging class of heterogeneous catalysts that with great potential in the catalytic conversion of CO_(2)to value-added products because of their attractive features,such as abundant metal active sites,inherent porosity,and easy functionalities.Herein,a unique three-dimensional(3D)MOF,{(CH_(3)NH_(2)CH_(3))_(2)[Co_(3)(BCP)_(2)]·6H_(2)O·4DMF}n(1)(H_(4)BCP:5‐(2,6‐bis(4‐carboxyphenyl)pyridin‐4‐yl)isophthalic acid;DMF:N,N'‐dimethylformamide),was synthesized using carboxylic acid ligands and cobalt salts via a solvothermal method.According to structural analysis,[Co_(3)]clusters as secondary building units(SBU)are bridged by BCP4−ligands,forming an anion framework with flu topology,and dimethylamine cations act as counter ions in the pores.The framework has rectangular channels of approximately 0.4 nm×0.9 nm along the a-axis direction,exhibiting its porous property.Infrared spectroscopy(IR)and X-ray photoelectron spectroscopy(XPS)characterizations proved the coordination interaction between the carboxyl groups in the ligands and the metal ions.The powder X-Ray diffraction(PXRD)test further confirmed the phase purity of the synthesized samples.PXRD and thermogravimetry(TG)analyses indicated that 1 possessed good solvent and thermal stabilities.The catalytic experiments revealed that 1 could effectively catalyze CO_(2)with aziridines or propargyl amines to prepare oxazolidinones.In the cycloaddition of CO_(2)with aziridines,1 can facilitate the reaction under relatively mild conditions compared to other reported MOF-based catalysts.It shows excellent universality for substrates with various substitutions on the N atom or benzene ring.Investigation of the mechanism indicated that the coordination interaction of cobalt metal sites with the nitrogen atoms of aziridines can activate the substrates.For the carboxylative cyclization of CO_(2)with propargylic amines,this catalyst also has a broad substrate scope.Control experiments and nuclear magnetic resonance(NMR)tests suggest that Lewis acid metal sites are responsible for the high catalytic efficiency achieved by activating the alkyne groups.Moreover,1 showed good reusability in both reactions.Compound 1 represents a new catalyst that enables“two birds with one stone”in the catalytic synthesis of oxazolidinones using CO_(2).
基金Project(22109181)supported by the National Natural Science Foundation of ChinaProject(2022JJ40576)supported by the Hunan Provincial Natural Science Foundation of China。
文摘Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power density.However,the low energy density and the lack of sustainable design strategies for the cathodes hinder the practical application of ZIHCs.Herein,we design the N and O co-doped porous carbon cathode by annealing metal-organic framework(ZIF-8).ZIF-8 retains the original dodecahedral structure with a high specific surface(2814.67 m^(2)/g)and I_(G)/I_(D) ratio of 1.0 during carbonization and achieves self-doping of N and O heteroatoms.Abundant defect sites are introduced into the porous carbon to provide additional active sites for ion adsorption after the activation of carbonized ZIF-8 by KOH treatment.The ZIHCs assembled with modified ZIF-8 as the cathode and commercial zinc foil as the anode show an energy density of 125 W∙h/kg and a power density of 79 W/kg.In addition,this ZIHCs device achieves capacity retention of 77.8%after 9000 electrochemical cycles,which is attributed to the diverse pore structure and plentiful defect sites of ZIF-8-800(KOH).The proposed strategy may be useful in developing high-performance metal-ion hybrid capacitors for large-scale energy storage.
文摘Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)O dis-solved in N,N-dimethylformamide,and were converted into Fe-Co embedded in N-doped porous carbon polyhedra by pyrolysis in a nitrogen atmosphere.During pyrolysis,the or-ganic ligands transformed into N-doped porous carbon which improved their structural stability and also their electrical contact with other materials.The Fe and Co are tightly bound together because of their encapsulation by the carbon nitride and are well dispersed in the carbon matrix,and improve the material’s conductivity and stability and provide additional capacity.When used as the anode for lithium-ion batteries,the material gives an initial capacity of up to 2230.7 mAh g^(-1)and a reversible capa-city of 1146.3 mAh g^(-1)is retained after 500 cycles at a current density of 0.5 A g^(-1),making it an excellent candidate for this purpose.
基金Project(20070006011) supported by the Doctoral Foundation of Ministry of Education of China
文摘The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal vehicle dynamics model was built by taking the information delay into consideration, and three typical information frameworks, i.e., leader-predecessor framework (LPF), multiple-predecessors framework (MPF) and predecessor-successor framework (PSF), were defined and their related spacing error dynamics models in frequency domain were proposed. The string stability of platoon of automated vehicles was analyzed for the LPF, MPF and PSF, respectively. Meanwhile, the related sufficient string stable conditions were also obtained. The results demonstrate that the string stability can be guaranteed tbr the LPF and PSF with considering the information delay, but the ranges of the control gains of the control laws are smaller than those without considering the information delay. For the MPF, the "weak" string stability, which can be guaranteed without considering the information delay, cannot be obtained with considering the information delay. The comparative simulations further demonstrate that the LPF shows better string stability, but the PSF shows better string scalable performance.
基金Project(51674114)supported by the National Natural Science Foundation of ChinaProject(2019JJ40069)supported by the Natural Science Foundation of Hunan Province,ChinaProject(16K025)supported by the Key Laboratory of the Education Department of Hunan Province,China
文摘A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIBs).The effect of reaction temperature and time on morphologies of Sb2O3 was studied.The results from SEM and TEM demonstrate that the tremella-like Sb2O3 architecture are composed of numerous nanosheets with high specific surface area.When the tremella-like Sb2O3 was used as LIBs anode,the discharge and charge capacities can achieve 724 and 446 mA·h/g in the first cycle,respectively.Moreover,the electrode retains an impressive high capacity of 275 mA·h/g even after 50 cycles at 20 mA/g,indicating that the material is extremely promising for application in LIBs.
文摘Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.
文摘Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.
基金supported by National Natural Science Foundation of China(project no.51676100)。
文摘Energetic metal-organic complexes have been involved in nanothermites as novel oxidants.However,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still limited.In this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.