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Nanoscale three-dimensional (3D) printing of metals and alloys has faced challenges in speed, miniaturization and deficiency in material properties. Traditional nanomanufacturing relies on lithographic methods with material constraints, limited resolution and slow layer-by-layer processing. This work introduces polymer-free techniques using two-photon decomposition and optical force trapping for free-space direct 3D printing of metals, metal oxides and multimetallic alloys with resolutions beyond optical limits. This method involves the two-photon decomposition of metal atoms from precursors, rapid assembly into nanoclusters via optical forces and ultrafast laser sintering, yielding dense, smooth nanostructures. Enhanced near-field optical forces from laser-induced localized surface plasmon resonance facilitate nanocluster aggregation. Our approach eliminates the need for organic materials, layer-by-layer printing and complex post-processing. Printed Mo nanowires show an excellent mechanical performance, closely resembling the behaviour of single crystals, while Mo-Co-W alloy nanowires outperform Mo nanowires. This innovation promises the customizable 3D nanoprinting of high-quality metals and metal oxides, impacting nanoelectronics, nanorobotics and advanced chip manufacturing.
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Gossypol (Gsp) and antibiotics present in water bodies become organic pollutants that are harmful to human health and the ecological environment. Accurate and effective detection of these pollutants has far-reaching significance in many fields. A new three-dimensional metal-organic framework (MOF), {[Eu3(L)2(HCOO-)(H2O)3]·2H2O·2DMF}n (Eu-MOF), was synthesized from 3,5-bis(2,4-dicarboxylphenyl)nitrobenzene (H4L) ligand and Eu3+ via the solvothermal method in this paper. The Eu-MOF demonstrates strong red fluorescence and can remain stable in different pH solutions. The MOF fluorescence probe could detect organic pollutants through the "shut-off" effect, with a fast response speed and a low detection limit [Gsp, nitrofurantoin (NFT), and nitrofurazone (NFZ) for 0.43, 0.38, and 0.41 µM, respectively]. During the testing process, Eu-MOF exhibited good selectivity and recoverability. Furthermore, the mechanism of fluorescence quenching was investigated, and the recoveries were also good in real samples. This paper introduced a deep learning model to recognize the fluorescence images, a portable intelligent logic detector designed for real-time detection of Gsp by logic gate strategy, and an anticounterfeiting mark prepared based on inkjet printing. Importantly, this work provides a new way of thinking for the detection of organic pollutants in water with high sensitivity and practicality by combining the fluorescence probe with machine learning and logical judgment.
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Antibacterianos , Európio , Corantes Fluorescentes , Gossipol , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Európio/química , Antibacterianos/análise , Antibacterianos/química , Gossipol/análise , Gossipol/química , Poluentes Químicos da Água/análise , Nitrofuranos/análise , Espectrometria de Fluorescência , Estrutura Molecular , Limite de DetecçãoRESUMO
Excellent electrocatalytic CO2 reduction reaction activity has been demonstrated by transition metals and nitrogen-codoped carbon (M-N-C) catalysts, especially for transition-metal porphyrin (MTPP)-based catalysts. In this work, we propose to use one-step low-temperature pyrolysis of the isostructural MTPP-based metal-organic frameworks (MOFs) and electrochemical in situ reduction strategies to obtain a series of hybrid catalysts of Co nanoparticles (Co NPs) and MTPP, named Co NPs/MTPP (M = Fe, Co, and Ni). The in situ introduction of Co NPs can efficiently enhance the electrocatalytic ability of MTPP (M = Fe, Co, and Ni) to convert CO2 to CO, particularly for FeTPP. Co NPs/FeTPP endowed a high CO faradaic efficiency (FECOmax = 95.5%) in the H cell, and the FECO > 90.0% is in the broad potential range of -0.72 to -1.22 VRHE. In addition, the Co NPs/FeTPP achieved 145.4 mA cm-2 at a lower potential of -0.70 VRHE with an FECO of 94.7%, and the CO partial currents increased quickly to reach 202.2 mA cm-2 at -0.80 VRHE with an FECO of 91.6% in the flow cell. It is confirmed that Co NPs are necessary for hybrid catalysts to get superior electrocatalytic activity; Co NPs also can accelerate H2O dissociation and boost the proton supply capacity to hasten the proton-coupled electron-transfer process, effectively adjusting the adsorption strength of the reaction intermediates.
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The dual-ligand strategy was employed to synthesize a new microporous material, [Zn3(SNDC)(AmTAZ)3(H2O)]·H2O·CH3CN (1), incorporating sulfonic acid and amino groups for enhancing gas adsorption and separation. The activated 1 (named 1a) exhibited selective adsorption of acetylene over carbon dioxide and methane. Hence, the dual-ligand strategy optimized the pore environment and provided an effective approach for pure separation of gases.
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Metal-organic frameworks (MOFs) are considered one of the most significant electrocatalysts for the sluggish oxygen evolution reaction (OER). Hence, a series of novel N,S-codoped Ni-based heterometallic organic framework (HMOF) (NiM-bptz-HMOF, M = Co, Zn, and Mn; bptz = 2,5-bis((3-pyridyl)methylthio)thiadiazole) precatalysts are constructed by the heteroatom and second metal doping strategies. The effective combination of the two strategies promotes electronic conductivity and optimizes the electronic structure of the metal. By regulation of the type and proportion of metal ions, the electrochemical performance of the OER can be improved. Among them, the optimized Ni6Zn1-bptz-HMOF precatalyst exhibits the best performance with an overpotential of 268 mV at 10 mA cm-2 and a small Tafel slope of 72.5 mV dec-1. This work presents a novel strategy for the design of modest heteroatom-doped OER catalysts.
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Ethylene (C2H4) purification and propylene (C3H6) recovery are highly relevant in polymer synthesis, yet developing physisorbents for these industrial separation faces the challenges of merging easy scalability, economic feasibility, high moisture stability with great separation efficiency. Herein, we reported a robust and scalable MOF (MAC-4) for simultaneous recovery of C3H6 and C2H4. Through creating nonpolar pores decorated by accessible N/O sites, MAC-4 displays top-tier uptakes and selectivities for C2H6 and C3H6 over C2H4 at ambient conditions. Molecular modelling combined with infrared spectroscopy revealed that C2H6 and C3H6 molecules were trapped in the framework with stronger contacts relative to C2H4. Breakthrough experiments demonstrated exceptional separation performance for binary C2H6/C2H4 and C3H6/C2H4 as well as ternary C3H6/C2H6/C2H4 mixtures, simultaneously affording record productivities of 27.4 and 36.2â L kg-1 for high-purity C2H4 (≥99.9 %) and C3H6 (≥99.5 %). MAC-4 was facilely prepared at deckgram-scale under reflux condition within 3â hours, making it as a smart MOF to address challenging gas separations.
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Various naphthalenediimide (NDI) based electron donor-acceptor coordination polymers (D-A CPs) have been constructed and used to explore charge transfer (CT) and electron transfer (ET) behaviors. Up to now, significant progress has been made in the interface contact and electron donor-acceptor ability matching mechanism, while the electronic density effect of the electron donors on the CT and ET behaviors is still not known. Herein, two NDI-based D-A CPs, [Cd2(H2NDI)(IPA)2(H2O)2] (1) and [Cd2(H2NDI)(IPA-OH)2(H2O)2] (2), are constructed using an NDI-based ligand and two aromatic carboxylic acid ligands (H2NDI = 2,7-bis(3,5-dimethyl) dipyrazol-1,4,5,8-naphthalene tetracarboxydiimide, H2IPA = isophthalic acid; and H2IPA-OH = 5-hydroxyisophthalic acid). UV-vis and EPR spectroscopy and DFT calculations analyses reveal that the occurrence of themal electron transfer (TET) in 1 and 2 results from the HOMO of the IPA and IPA-OH lying higher than the LUMO of the NDI. Meanwhile, compared to 1, the UV-vis absorption spectrum of 2 exhibits a significant red shift, which suggests higher electron density of the donor and more electron transfer pathways are beneficial for the occurrence of intermolecular CT. After UV light irradiation, the comparison of the photochromic behavior of 1 and 2 confirms the negative effect of the stronger CT on photoinduced electron transfer (PET). The present study illustrates the delicate modulating effect of electron density on the CT and ET behaviors in D-A CPs.
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Oxidation and removal of highly toxic sulfides and amines are particularly important for environmental and human security but remain challenging. Here, incorporating an excellent photosensitizer, donor-acceptor-donor (D-A-D)-type 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic (H2L), into metal-organic frameworks (MOFs) has been manifested to promote the charge separation, affording four three-dimensional (3D) MOFs (isostructural 1-Co/1-Zn with Co2/Zn2 units, and 2-Gd/2-Tb with Gd/Tb-cluster chains) as photocatalysts in the visible light-driven air-O2-mediated catalytic oxidation and removal of hazardous phenylsulfides and benzylamines. Impressively, structure-property correlation illustrated that the transition metal centers assembled in MOFs play an important role in the photocatalytic activity, and we can conclude that 1-Zn can be a robust heterogeneous catalyst possessing good light adsorption and fast charge separation in oxidation removal reactions of both benzylamines and phenylsulfides under visible light irradiation and room temperature with excellent activity/selectivity, stability, and reusability.
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Separating acetylene (C2H2) from other light hydrocarbons and carbon dioxide (CO2) mixtures under mild conditions poses significant challenges due to the remarkably similar properties between C2H2 and those gases. For the goal of C2H2 separation, a F-functionalized organic linker, H2F-PyIP = 2-fluorine-5-(4-pyridyl)isophthalic acid, was designed, and the corresponding metal-organic framework (MOF), {[Co2(F-PyIP)2DMF]·4H2O}n (1), was constructed. The MOF with open channels decorated by the active sites of the F groups revealed the exceptional C2H2 uptake and selectivity over CO2, C2H4, and CH4. The breakthrough experiments with different molar ratios of C2H2-C2H4, C2H2-CO2, and other gas mixtures further verified superior separation capacity of the MOF. In particular, the dynamic separation time intervals for gas mixtures (C2H2/CO2 = 1:1, 1:5, 1:10, and 1:20) fell in the range 30-44 min, highlighting the potential of the MOF for tackling the challenging C2H2/CO2 separation process.
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Herein, a 2-fold interpenetrated metal-organic framework (MOF) Zn-BPZ-TATB with accessible N/O active sites in nonpolar pore surfaces was reported for one-step C2 H4 purification from C2 H6 or C3 H6 mixtures as well as recovery of C3 H6 from C2 H6 /C3 H6 /C2 H4 mixtures. The MOF exhibits the favorable C2 H6 and C3 H6 uptakes (>100â cm3 g-1 at 298â K under 100â kPa) as well as selective adsorption of C2 H6 and C3 H6 over C2 H4 . The C3 H6 - and C2 H6 -selective feature were investigated detailedly by experimental tests as well as sorption kinetic studyies. Molecular modelling revealed the multiple interactions between C3 H6 or C2 H6 molecules and methyl groups as well as triazine rings in pores. Zn-BPZ-TATB not only can directly generate 323.4â L kg-1 and 15.4â L kg-1 of high-purity (≥99.9 %) C2 H4 from C3 H6 /C2 H4 and C2 H6 /C2 H4 mixtures, but also provide a large high-purity (≥99.5 %) C3 H6 recovery capacity of 60.1â L kg-1 from C3 H6 /C2 H4 mixtures. More importantly, the high-purity C3 H6 (≥99.5 %) and C2 H4 (≥99.9 %) with the productivities of 38.2 and 12.7â L kg-1 can be simultaneously obtained from C2 H6 /C3 H6 /C2 H4 mixtures through a single adsorption/desorption cycle.
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Femtosecond laser-based technique called two-photon polymerization (TPP) has emerged as a powerful tool for nanofabrication and integrating nanomaterials. However, challenges persist in existing three-dimensional (3D) nanoprinting methods, such as slow layer-by-layer printing and limited material options due to laser-matter interactions. Here, we present an approach to 3D nanoprinting called free-space nanopainting, using an optical force brush (OFB). OFB enables precise spatial writing paths, instantaneous adjustment of linewidths and concentrations, and unrestricted resolution beyond optical limits. OFB allows rapid aggregation and solidification of radicals, resulting in narrower lines at lower polymerization thresholds and enhanced sensitivity to laser energy. This advancement enables high-accuracy free-space painting, analogous to Chinese brush painting on paper. The printing speed is increased substantially compared to layer-by-layer methods, from 100 to 1000 times faster. We successfully printed various bionic muscle models derived from 4D nanostructures with tunable mechanical properties, responsive to electrical signals, and excellent biocompatibility.
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The purification of industrially valuable C2H2 and C2H4 from multicomponent mixtures represents a crucial process in the chemical industry. In this study, we present a copper-based metal-organic framework (L-py-Cu) built on a nitrogen-rich organic linker that is capable of separating C2H2/C2H4/C2H6 and C2H2/CO2 mixtures, therefore producing highly pure C2H4 and C2H2, respectively. L-py-Cu exhibits favorable adsorption of C2H2 and C2H6 over C2H4 and thus achieves one-step C2H4 purification from C2H2/C2H4/C2H6 ternary mixtures, as verified by multicomponent breakthrough measurements. In addition, it can also extract C2H2 from C2H2/CO2 binary mixtures.
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Herein, we used the 4-fluoro-[1,1'-biphenyl]-3,4',5-tricarboxylic acid (H3fbptc) ligand to design and construct a new metal-organic framework (MOF), [Cu3(fbptc)2(H2O)3]·3NMP (1), which possesses rich accessible metal sites and F functional groups in the porous walls and shows high uptake for C2H2 (119.3 cm3 g-1) and significant adsorption selectivity for C2H2 over CH4 (14.4) and CO2 (3.6) at 298 K and 100 kPa. In particular, for the gas mixtures of C2H2-CH4 and C2H2-CO2, the MOF reveals large breakthrough time ratios (C2H2/CH4 = 13, C2H2/CO2 = 5.9), which are particularly prominent in dynamic breakthrough experiments, also confirming the excellent potential for the practical separation of C2H2 from two-component mixtures (C2H2-CH4 and C2H2-CO2) and even three-component mixtures (C2H2-CO2-CH4).
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Organic dyes as non-noble metal photosensitizers have attracted increasing attention due to their environmental friendliness and sustainability but suffer from fast deactivation and low stability. Here, we reported a fruitful strategy by the confinement and stabilization of visible light-active signal unit organic dyes within the metal-organic frameworks (MOFs) and developed a series of heterogeneous photocatalysts dye@UiO-66s [dye = fluorescein (FL)/rhodamine B (RhB)/eosin Y (EY), UiO-66s = UiO-66, and Bim-UiO-66]. It has been demonstrated that the encapsulated dyes can effectively sensitize MOF hosts and dominate the band structures and photocatalytic activities of dye@UiO-66s regardless of the ligand functionalization of MOFs. Photocatalytic experiments showed that these dye@UiO-66s exhibit enhanced activities relative to free dyes and among them, FL@Bim-UiO-66 displays excellent efficiencies toward the green synthesis of new carbon-bridged annulations, [1,2,5]thiadiazole[3,4-g]benzoimidazoles in the yield of up to 98% at room temperature with outstanding stability and reusability. Furthermore, the intramolecular cyclization intermediate was captured and characterized by the single-crystal X-ray diffraction analysis.
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Implementing the dual-ligand strategy, a microporous Zn-based MOF 1 with nitro and amino groups was effectively produced. The activated interconnected pores of 1 exhibited high C2H2 uptake capacity and preferential adsorption behaviour for C2H2 over CO2, as identified by the experiments and simulations. This work provides a new approach for designing and synthesizing the MOFs with desired structures and properties by optimizing their pore environment via the dual-ligand strategy.
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ETHNOPHARMACOLOGICAL RELEVANCE: Danggui Buxue Decoction (DBD) is a classic prescription of traditional Chinese medicine that is mainly used for treating clinical anemia for more than 800 years. This prescription has been utilized for nourishing "Qi" and enriching "Blood" for women suffering from menopausal symptoms. Meanwhile, DBD has the role of improving angiogenesis and promoting the neuroprotective functions. Bone marrow-derived endothelial progenitor cells (EPCs) was suboptimal to treat the focal cerebral ischemia (FCI). Thus, it's may be a novel strategy of DBD combined with EPCs transplantation for the FCI. AIM OF THE STUDY: To investigate the mechanistic effects of DBD in combination with EPCs transplantation to improve behavioral function of the FCI and hyperlipidemia. MATERIALS AND METHODS: We used rats with hyperlipidemia to develop a FCI model using photo-thrombosis, and treated the DBD in combination with EPCs transplantation. We adopted the Modified Neurological Severity Score to evaluate the neurological deficit, undertook the 2,3,5-triphenyltetrazolium chloride staining to calculate the total infarct volume. We carried out the RT-qPCR, Immunohistochemical analyses, TUNEL, ELISA, and Western blotting to measure the gene and protein levels which related to anti-apoptosis mechanisms and angiogenesis. RESULTS: Administration of DBD in combination with EPCs transplantation was found to improve behavioral function, reducing the infarct volume and decrease the level of total-cholesterole (TC) and low-density lipoprotein-cholesterol (LDL-C). Treatment of DBD plus EPCs increased the mRNA and protein expression of vascular endothelial growth factor A, fibroblastic growth factor-2, and angiopoietin-1 and decreased the apoptosis of endothelial cells by activating the phosphoinositide 3-kinase/protein kinase B/Bcl-xL/Bcl-2 associated death promoter (PI3K/Akt/BAD) pathway and promoting activation of the extracellular signal-regulated kinase (ERK) pathway, which induced angiogenesis directly. CONCLUSIONS: Our findings provided that DBD administration combined with EPCs transplantation promoted reconstruction of nervous function. This was achieved by enhancing expression of the growth factors related to anti-apoptosis mechanisms and angiogenesis thanks to regulation of the PI3K/Akt/BAD and ERK signaling pathways, and might be relate to the lowering of TC and LDL-C levels.
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Isquemia Encefálica , Células Progenitoras Endoteliais , Hiperlipidemias , Ratos , Feminino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Progenitoras Endoteliais/metabolismo , Fosfatidilinositol 3-Quinases , Fator A de Crescimento do Endotélio Vascular/genética , LDL-Colesterol , Hiperlipidemias/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto CerebralRESUMO
Amino (-NH2)-functionalized metal-organic frameworks (MOFs) are widely applied to improve the properties of materials owing to the rich host-guest chemical properties of amino groups. In this work, the amino-functionalization strategy was thus employed to improve the sorption performance of methylene blue (MB). The introduction of -NH2 groups in AOBTC-Zn did not reduce the pore size of the framework but rather modulated and optimized the host-guest interactions of MOFs. The MB+ sorption result was significantly improved by the NH2-functionalized NH2-AOBTC-Zn. The results showed that the maximum sorption capacity of NH2-AOBTC-Zn is much higher (1623 mg/g) than that of AOBTC-Zn (204 mg/g), which was comparable with that of MIL-68(Al) (1666 mg/g). The adsorption kinetics and isothermal models indicated that the MB+ sorption processes of both MOFs were consistent with the Langmuir isothermal and pseudo-second-order kinetic models. The single-group and multicomponent sorption experiments showed that the sorption behavior was the result of π-π interaction, electrostatic interaction, hydrogen bonding interaction, and pore size interaction. In particular, NH2-AOBTC-Zn exhibits a higher adsorption capacity than AOBTC-Zn due to the additional hydrogen bonding interactions it provided. These may guide the design of porous MOFs with side group modification for liquid phase sorption/separation.
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In recent years, the irrational use of antibiotics has become very widespread. It is necessary to regulate this phenomenon through antibiotic detection. In this work, a series of isomorphic Ln-MOFs (Ln = Tb3+ and Eu3+) were synthesized from 1,3,5-tri(4-carboxyphenyl)benzene (H3L) and Ln3+ by the solvothermal method for the first time. A series of 1-EuxTb1-x with different luminescence were doped by changing the molar ratio of Tb3+ and Eu3+. Ln3+ forms a 4-connected 2D network structure through self-assembly with fully deprotonated L3-. It shows good chemical stability in water, and its luminescence is not affected by aqueous solutions with different pH values. 1-Eu demonstrates rapid and sensitive detection capabilities for MDZ and TET with good recyclability and low detection limits (10-5). In order to increase the practicability of 1-Eu, two portable sensors have been prepared, in which the fluorescent film (Film@1-Eu) has a detection limit of 10-4, and the sensitivity is only less than 10% of the titration results. A portable fluorescent test paper can reach the detection limit of 14.7 ppm. This study provides a new idea for the application of stable multifunctional materials in the field of fluorescence sensing.
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Stimuli-induced structural transformation of supramolecular cages has drawn increasing attention because of their sensitive feature to external variations as model systems to simulate biological processes. However, combining structural transformation and useful functions has remained a difficult task. This study reports the solvato-controlled self-assembly of two unique topologies with different emission characteristics, a water-soluble Ag8 L4 cage (A) and an Ag4 L2 cage (B), produced from the same sulfonate-pendant tetraphenylethene (TPE) bridged tetrakis-(1,2,4-triazolium) ligand. Both cages show interesting solvent-responsive reversible structural transformation, and the change of fluorescence signals can efficiently track the process. Additionally, water-soluble cage A exhibits unique properties in thermochromism, thiol amino acid sensing, and subcellular imaging in aqueous media.
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The utilization of dative BâN bonds for the creation of crystalline organic framework (BNOF) has increasingly received intensive interest; however, the shortage of permanent porosity is an obstacle that must be overcome to guarantee their application as porous materials. Here, we report the first microporous crystalline framework, BNOF-1, that is assembled through sole monomers, which can be scalably synthesized by the cheap 4-pyridine boronic acid. The 2D networks of BNOF-1 were stacked in parallel to generate a highly porous supramolecular open framework, which possessed not only the highest BET surface area of 1345 m2 g-1 amongst all of the BNOFs but also features a record-high uptake of C2H2 and CO2 in covalent organic framework (COF) materials to date. Dynamic breakthrough experiments demonstrated that BNOF-1 material can efficiently separate C2H2/CO2 mixtures. In addition, the network can be regenerated in organic solvents with no loss in performance, making its solution processable. We believe that BNOF-1 would greatly diversify the reticular chemistry and open new avenues for the application of BNOFs.