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1.
Artigo em Inglês | MEDLINE | ID: mdl-36691771

RESUMO

Developing porous materials for C3H6/C3H8 separation faces the challenge of merging excellent separation performance with high stability and easy scalability of synthesis. Herein, we report a robust Hofmann clathrate material (ZJU-75a), featuring high-density strong binding sites to achieve all the above requirements. ZJU-75a adsorbs large amount of C3H6with a record high storage density of 0.818 g mL-1, and concurrently shows high C3H6/C3H8 selectivity (54.2) at 296 K and 1 bar. Single-crystal structure analysis unveil that the high-density binding sites in ZJU-75a not only provide much stronger interactions with C3H6 but also enable the dense packing of C3H6. Breakthrough experiments on gas mixtures afford both high separation factor of 14.7 and large C3H6 uptake (2.79 mmol g-1). This material is highly stable and can be easily produced at kilogram-scale using a green synthesis method, making it as a benchmark material to address major challenges for industrial C3H6/C3H8 separation.

2.
Research (Wash D C) ; 2022: 9869510, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340506

RESUMO

The manipulation on turn-on fluorescence in solid state materials attracts increasing interests owing to their widespread applications. Herein we report how the nonradiative pathways of tetraphenylpyrazine (TPP) units in metal-organic frameworks (MOFs) systems could be hindered through a topological design approach. Two MOFs single crystals of different topology were constructed via the solvothermal reaction of a TPP-based 4,4',4″,4‴-(pyrazine-2,3,5,6-tetrayl) tetrabenzoic acid (H4TCPP) ligand and metal cations, and their mechanisms of formation have been explored. Compared with the innate low-frequency vibrational modes of flu net Tb-TCPP-1, such as phenyl ring torsions and pyrazine twists, Tb-TCPP-2 adopts a shp net, so the dihedral angle of pyrazine ring and phenyl arms is larger, and the center pyrazine ring in TPP unit is coplanar, which hinders the radiationless decay of TPP moieties in Tb-TCPP-2. Thereby Tb-TCPP-2 exhibits a larger blue-shifted fluorescence and a higher fluorescence quantum yield than Tb-TCPP-1, which is consistent with the reduced nonradiative pathways. Furthermore, Density functional theory (DFT) studies also confirmed aforementioned tunable turn-on fluorescence mechanism. Our work constructed TPP-type MOFs based on a deliberately topological design approach, and the precise design of turn-on fluorescence holds promise as a strategy for controlling nonradiative pathways.

3.
RSC Adv ; 12(36): 23411-23415, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090424

RESUMO

Hydrogen-bonded organic frameworks (HOFs) have received tremendous attention in recent years due to the good designability. However, the pure organic nature of HOFs sometimes limits the application development and performance improvement. Functionalizing is an effective strategy to control and modulate material properties, which can achieve properties that cannot be achieved by a pristine material. Herein, a series of HOF-76⊃DSMI were synthesized through functionalizing the stable AIE-based HOF-76 by incorporating a red dye which complements the deficiency of the red component of HOF-76. Then, a single matrix white light-emitting diode (WLED) was fabricated by coating the HOF-76⊃DSMI material on a 460 nm blue LED with CIE chromaticity coordinates of (0.333, 0.329), a correlated colour temperature (CCT) of 5490 K and a colour rendering index (CRI) of 80.

4.
Angew Chem Int Ed Engl ; 61(41): e202211523, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35979632

RESUMO

Developing porous materials to overcome the trade-off between adsorption capacity and selectivity for C2 H2 /CO2 separation remains a challenge. Herein, we report a stable HKUST-1-like MOF (ZJU-50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2 H2 storage and selectivity. ZJU-50a exhibits one of the highest C2 H2 storage capacity (192 cm3 g-1 ) and concurrently high C2 H2 /CO2 selectivity (12) at 298 K and 1 bar. Single-crystal X-ray diffraction studies on gas-loaded ZJU-50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2 H2 molecule but not CO2 to result in both high C2 H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2 H2 /CO2 mixtures, providing a high C2 H2 recovery capacity of 84.2 L kg-1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade-off for this separation.

5.
Small ; 18(35): e2203105, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35931456

RESUMO

Optimizing the adsorption free energy and promoting the active phase transition to further enhance the oxygen evolution reaction (OER) activity remain significant challenges. The adsorption free energy can be optimized by modulating the electronic structure and adjusting the crystal configuration. Meanwhile, the transformation of the active phase can be promoted by introducing strain energy. The theoretical calculations are conducted to verify the rational envisage. However, it is still a great obstacle to introducing strain into the electrocatalysts and avoiding destruction. The stress field caused by dislocation can realize both of the above. Hence, the molten salt with the bound water method is proposed and the abundant dislocation layered double hydroxides (D-NiFe LDH) are constructed. The in situ characterizations further verify the dislocations significantly affect the generation of the active phase and the state of electronic structure. Consequently, the D-NiFe LDH exhibits outstanding OER activity and obtains 10 mA cm-2 , only requiring 199 mV overpotential with fabulous stability (100 mA cm-2 more than 24 h). The work paves a new avenue for the rational introduction dislocations to optimize the crystal configuration and boost the active phase formation, significantly enhancing the OER performance.

6.
Adv Sci (Weinh) ; 9(17): e2200953, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35403835

RESUMO

Nonlinear optical (NLO) switch materials have attracted considerable attention in photonics. Although various materials based on complex structural transitions have been developed extensively, the studies on light-driven up-conversion laser switches are rare, which have advantages including easy operations at room temperature and high contrasts. Here, the concept of photoswitch building unit is proposed to construct a novel sandwich-like mixed-matrix membrane. Dye@metal-organic framework (MOF) crystals and spirooxazine are regarded as the laser emission and absorption units, followed by their hierarchical encapsulation into the polydimethylsiloxane carrier unit. Excited MOF microcrystals exhibit two-photon pumped lasing anisotropy, with an ultrahigh degree of linear polarization (≈99.9%). Photochromic molecules can be interconverted by the external ultraviolet stimulus, causing sharp absorption-band variations and inducing the laser emission or quenching. Such up-conversion polarized laser switch material is reported for the first time. Record-high NLO contrast (≈6.1 × 104 ) among the solid-state NLO switch materials can be obtained through simultaneously controlling the ultraviolet irradiation and the emission-detected polarization direction at room temperature.

7.
Front Chem ; 10: 852402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295977

RESUMO

Considering that metal-organic framework (MOF)-polymer mixed-matrix membranes (MMMs) can overcome the drawbacks of intrinsic fragility and poor processability of pure-MOF membranes, we designed MOF-based MMMs for efficient removal and fast fluorescence sensing of heavily toxic ions within water systems simultaneously. In this work, a series of MOF-based MMMs are prepared by mixing a hydrolytically stable cationic [Eu7 (mtb)5(H2O)16]·NO3 8DMA·18H2O (denoted as Eu-mtb) MOF material into poly (vinylidene fluoride) with high loadings up to 70%. The free volume at the interface between the polymer and Eu-mtb particles, combined with the permanent porosity and uniform distribution of Eu-mtb particles, enables these MMMs to show fast enrichment of Cr2O7 2- from solutions and consequently have a full contact between the analyte and MOFs. The developed Eu-mtb MMM (70wt% loading) thus shows both efficient removal and exceptional fluorescence sensing of Cr2O7 2- in aqueous media. The overall adsorption capacity of the Eu-mtb MMM (70 wt% loading) for Cr2O7 2- reaches up to 33.34 mg/g, which is 3.4 times that of powder-form Eu-mtb. The detection limit of the Eu-mtb MMM (70 wt% loading) for Cr2O7 2- is around 5.73 nM, which is lower than that of the reported powder-form Eu-mtb. This work demonstrates that it is feasible to develop flexible luminescent MOF-based MMMs as a significant platform for efficient removal and sensitive sensing of pollutants from water systems simultaneously.

8.
Adv Sci (Weinh) ; 9(11): e2105556, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35146963

RESUMO

Developing efficient and stable water adsorbents for adsorption-driven heat transfer technology still remains a challenge due to the lack of efficient strategies to enhance low-pressure water uptakes. The authors herein demonstrate that the immobilization of Lewis basic nitrogen sites into metal-organic frameworks (MOFs) can improve water uptake and target benchmark coefficient of performances (COPs) for cooling and heating. They present the water sorption properties of a chemically stable MOF (termed as Zr-adip), designed by incorporating hydrophilic nitrogen sites into the adsorbent MIP-200. Zr-adip exhibits S-shaped sorption isotherms with an extremely high water uptake of 0.43 g g-1  at 303 K and P/P0  = 0.25, higher than MIP-200 (0.39 g g-1 ), KMF-1 (0.39 g g-1 ) and MOF-303 (0.38 g g-1 ). Theoretical calculations reveal that the incorporated N sites can serve as secondary adsorption sites to moderately interact with water, providing more binding sites to strengthen the water binding affinity. Zr-adip achieves exceptionally high COPs of 0.79 (cooling) and 1.75 (heating) with a low driving temperature of 70 °C, outperforming MIP-200 (0.78 and 1.53) and KMF-1 (0.75 and 1.74). Combined with its ultrahigh stability, excellent cycling performance, and easy regeneration, Zr-adip represents one of the best water adsorbents for adsorption-driven cooling and heating.

9.
J Am Chem Soc ; 144(7): 3200-3209, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138086

RESUMO

The discovery of high-performance adsorbents for highly efficient separation of xenon from krypton is an important but challenging task in the chemical industry due to their similar size and inert spherical nature. Herein, we report two robust and radiation-resistant Hofmann-type MOFs, Co(pyz)[Ni(CN)4] and Co(pyz)[Pd(CN)4] (termed as ZJU-74a-Ni and ZJU-74a-Pd), featuring oppositely adjacent open metal sites and perfect pore sizes (4.1 and 3.8 Å) comparable to the kinetic diameter of xenon (4.047 Å), affording the benchmark binding affinity for polarizable Xe gas. These materials thus exhibit both record-high Xe uptake capacities (89.3 and 98.4 cm3 cm-3 at 296 K and 0.2 bar) and Xe/Kr selectivities (74.1 and 103.4) at ambient conditions, all of which are the highest among all the state-of-the-art materials reported so far. The locations of Xe molecules within ZJU-74a-Ni have been visualized by single-crystal X-ray diffraction studies, in which two oppositely adjacent metal centers combined with the right aperture size can construct a unique sandwich-like binding site to offer unprecedented and ultrastrong Ni2+-Xe-Ni2+ interactions with xenon, thus leading to the record Xe capture capacity and selectivity. The excellent separation capacity of ZJU-74a-Pd was verified by breakthrough experiments for Xe/Kr gas mixtures, providing both unprecedentedly high xenon uptake capacity (4.63 mmol cm-3) and krypton productivity (214 cm3 g-1).

10.
J Am Chem Soc ; 144(6): 2614-2623, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35109657

RESUMO

Purification of C2H4 from a ternary C2H2/C2H6/C2H4 mixture by one-step adsorption separation is of prime importance but challenging in the petrochemical industry; however, effective strategies to design high-performance adsorbents are lacking. We herein report for the first time the incorporation of Lewis basic sites into a C2H6-selective MOF, enabling efficient one-step production of polymer-grade C2H4 from ternary mixtures. Introduction of amino groups into highly stable C2H6-selective UiO-67 can not only partition large pores into smaller cagelike pockets to provide suitable pore confinement but also offer additional binding sites to simultaneously enhance C2H2 and C2H6 adsorption capacities over C2H4. The amino-functionalized UiO-67-(NH2)2 thus exhibits exceptionally high C2H2 and C2H6 uptakes as well as benchmark C2H2/C2H4 and C2H6/C2H4 selectivities, surpassing all of the C2H2/C2H6-selective materials reported so far. Theoretical calculations combined with in situ infrared spectroscopy indicate that the synergetic effect of suitable pore confinement and functional surfaces decorated with amino groups provides overall stronger multipoint van der Waals interactions with C2H2 and C2H6 over C2H4. The exceptional performance of UiO-67-(NH2)2 was evidenced by breakthrough experiments for C2H2/C2H6/C2H4 mixtures under dry and wet conditions, providing a remarkable C2H4 productivity of 0.55 mmol g-1 at ambient conditions.

11.
ACS Omega ; 7(2): 2244-2251, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35071913

RESUMO

The rational design and synthesis of a highly efficient and cost-effective electrocatalyst for hydrogen evolution reaction (HER) are of great importance for the efficient generation of sustainable energy. Herein, amorphous/crystalline heterophase Ni-Mo-O/Cu (denoted as a/c Ni-Mo-O/Cu) was synthesized by a one-pot electrodeposition method. Thanks to the introduction of metallic Cu and the formation of amorphous Ni-Mo-O, the prepared electrocatalyst exhibits favorable conductivity and abundant active sites, which are favorable to the HER progress. Moreover, the interfaces consisting of Cu and Ni-Mo-O show electron transfers between these components, which might modify the absorption/desorption energy of H atoms, thus accelerating HER activity. As expected, the prepared a/c Ni-Mo-O/Cu possesses excellent HER performance, which affords an ultralow overpotential of 34.8 mV at 10 mA cm-2, comparable to that of 20 wt % Pt/C (35.0 mV), and remarkable stability under alkaline conditions.

12.
J Mol Histol ; 52(4): 823-838, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34097178

RESUMO

The aim of the present study was to investigate the role and potential regulatory mechanisms of fascin in the invasion and epithelial-to-mesenchymal transition of pituitary adenoma cells. A total of 30 specimens were assessed in the present study. The expression levels of fascin in the invasive pituitary adenoma group and non-invasive pituitary adenoma group were determined by immunochemistry. Fascin was downregulated via small interfering RNA in mouse pituitary AtT-20 cells. The proliferation, cell cycle and apoptosis of AtT-20 cells were assessed using Cell Counting Kit­8 and flow cytometry. The invasion of AtT-20 cells was detected using a Transwell assay. Transmission electron microscopy was utilized to observe the ultrastructure of AtT-20 cells. Real-time quantitative PCR, Western blotting and immunofluorescence staining were utilized to detect the expression levels of fascin and EMT markers. In the present study, fascin expression and clinical characteristics were not significantly correlated in pituitary adenoma. The protein expression level of fascin in invasive pituitary adenoma was higher than that in non-invasive pituitary adenoma, as assessed by immunochemistry. Downregulation of fascin resulted in significant decreases in cell viability, proliferation and invasion, arrested the cell cycle at the G1 phase and increased apoptosis. In addition, downregulation of fascin significantly decreased the expression levels of N-cadherin, the mesenchymal cell marker vimentin and the transcription factor Twist but significantly increased the expression levels of the epithelial cell marker E-cadherin. Further experiments revealed that overexpression of E-cadherin resulted in significant decreases in cell viability, proliferation, invasion, and the expression of fascin and transcription factor Twist and also arrested the cell cycle at the G2 phase. The results of the present study suggest that suppressing the expression level of fascin could regulate the invasion, proliferation and apoptosis of pituitary tumour cells and alter the expression level of various EMT markers. The present study identified that fascin effectively promotes the invasion, proliferation and apoptosis of pituitary tumour cells partially via the EMT pathway.


Assuntos
Adenoma/patologia , Proteínas de Transporte/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Proteínas dos Microfilamentos/fisiologia , Neoplasias Hipofisárias/patologia , Adenoma/genética , Adulto , Idoso , Antígenos CD/genética , Apoptose/genética , Western Blotting , Caderinas/genética , Ciclo Celular , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Hipofisárias/genética , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Células Tumorais Cultivadas , Vimentina/genética
13.
Angew Chem Int Ed Engl ; 60(29): 15995-16002, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33977622

RESUMO

Separation of acetylene from carbon dioxide remains a daunting challenge because of their very similar molecular sizes and physical properties. We herein report the first example of using copper(I)-alkynyl chemistry within an ultra-microporous MOF (CuI @UiO-66-(COOH)2 ) to achieve ultrahigh C2 H2 /CO2 separation selectivity. The anchored CuI ions on the pore surfaces can specifically and strongly interact with C2 H2 molecule through copper(I)-alkynyl π-complexation and thus rapidly adsorb large amount of C2 H2 at low-pressure region, while effectively reduce CO2 uptake due to the small pore sizes. This material thus exhibits the record high C2 H2 /CO2 selectivity of 185 at ambient conditions, significantly higher than the previous benchmark ZJU-74a (36.5) and ATC-Cu (53.6). Theoretical calculations reveal that the unique π-complexation between CuI and C2 H2 mainly contributes to the ultra-strong C2 H2 binding affinity and record selectivity. The exceptional separation performance was evidenced by breakthrough experiments for C2 H2 /CO2 gas mixtures. This work suggests a new perspective to functionalizing MOFs with copper(I)-alkynyl chemistry for highly selective separation of C2 H2 over CO2 .

14.
ACS Appl Mater Interfaces ; 13(16): 18792-18799, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33848119

RESUMO

Realization of ethane-selective porous materials for efficient ethane/ethylene (C2H6/C2H4) separation is an important task in the petrochemical industry. Although a number of C2H6-selective adsorbents have been realized, their adsorption capacity and selectivity might be mostly dampened under humid conditions due to structure decomposition or co-adsorption of water vapor. A desired material should have simultaneously high C2H6 uptake and selectivity, excellent water stability, and ultralow water adsorption uptake for industrial applications, but such a material is elusive. Herein, we report a chemically stable hafnium-based material (Hf)DUT-52a, featuring the suitable pore apertures and less hydrophilicity for highly efficient C2H6/C2H4 separation under humid conditions. Gas sorption results reveal that (Hf)DUT-52a exhibits both high ethane adsorption capacity (4.02 mmol g-1) and C2H6/C2H4 selectivity (1.9) at 296 K and 1 bar, which are comparable to the majority of the top-performing materials. Most importantly, the less pore hydrophilicity enables (Hf)DUT-52a to exhibit a negligible water uptake of 0.036 g g-1 before 40% relative humidity (RH), effectively minimizing the impact of humidity on separation capacity. This material thus shows excellent separation capacity even under 40% RH with a high polymer-grade ethylene production capacity up to 8.43 L kg-1 at ambient conditions, as evidenced by the breakthrough experiments.

15.
Angew Chem Int Ed Engl ; 60(18): 10304-10310, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33630416

RESUMO

For the separation of ethane from ethylene, it remains challenging to target both high C2 H6 adsorption and selectivity in a C2 H6 -selective material. Herein, we report a reversible solid-state transformation in a labile hydrogen-bonded organic framework to generate a new rod-packing desolvated framework (ZJU-HOF-1) with suitable cavity spaces and functional surfaces to optimally interact with C2 H6 . ZJU-HOF-1 thus exhibits simultaneously high C2 H6 uptake (88 cm3 g-1 at 0.5 bar and 298 K) and C2 H6 /C2 H4 selectivity (2.25), which are significantly higher than those of most top-performing materials. Theoretical calculations revealed that the cage-like cavities and functional sites synergistically "match" better with C2 H6 to provide stronger multipoint interactions with C2 H6 than C2 H4 . In combination with its high stability and ultralow water uptake, this material can efficiently capture C2 H6 from 50/50 C2 H6 /C2 H4 mixtures in ambient conditions under 60 % RH, providing a record polymer-grade C2 H4 productivity of 0.98 mmol g-1 .

16.
Small ; 17(6): e2006649, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33470526

RESUMO

Two europium metal-organic frameworks (MOFs) based on the same ligand, named as ZJU-23-Eu and ZJU-24-Eu, are selectively synthesized by fine-tuning solvent contents to tailor the coordination modes. Eu atoms are eight-coordinated and nine-coordinated in ZJU-23-Eu and ZJU-24-Eu respectively, and their frameworks vary in both spatial connectivity and symmetry. The ligand not only has multiphoton response but also suitable triplet energy level (19 998 cm-1 ) to sensitize Eu3+ . Thus ZJU-23-Eu exhibits characteristic emission of Eu3+ peaking at 614 nm via the energy transfer from the two-/three-photon excited ligand to Eu3+ , with its bidimensional layered structure benefiting this process. In contrast, the changed spatial connectivity in tridimensional ZJU-24-Eu narrows the distances between adjacent Eu3+ ions and reduces the density, resulting in poor two-photon excited fluorescence. Besides, noncentrosymmetric ZJU-24-Eu shows second harmonic generation (SHG) response with an intensity of ≈6.2 times relative to KH2 PO4 (KDP) microcrystalline powder while centrosymmetric ZJU-23-Eu cannot. These results have established two nonlinear optical (NLO) models based on MOFs to synchronously analyze the effects of two structural variables on different NLO behaviors, and provide ingenious ways to design MOF-based NLO devices with function on demand.

17.
Int J Neurosci ; 131(8): 810-827, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32326790

RESUMO

INTRODUCTION: The expression levels of signal transducer and activator of transcription 3 (STAT3) protein and Fascin-1 were inhibited using the STAT3 inhibitor BP-1-102 and RNA interference, respectively, to investigate the expression of AtT20 in mouse pituitary cells. The proliferative capacity and related molecular mechanisms of pituitary tumor cells were then analyzed. METHODS: Mouse AtT20 pituitary adenoma cells were divided into a control group (Pa group), a STAT3 inhibitor vehicle group (PA + DMSO group), a STAT3 inhibitor group (PA + BP-1-102 group), a Fascin-1 negative control group (PA + neg-siRNA group) and a Fascin-1 silenced group (PA + Fascin-siRNA group). The related protein expression and cell proliferation of the five groups were measured using immunofluorescence, Western blot and real-time RT-PCR, whereas their apoptosis and cell cycle were evaluated using CCK-8 and flow cytometry. RESULTS: Proliferation of AtT20 cells is inhibited with BP-1-102 enhanced apoptosis, at the same time reduced the expression of Fascin-1 and N-cadherin, and increased the expression of E-cadherin. After inhibiting Fascin-1, the expression of STAT3 decreased, the expression of N-cadherin decreased and the expression of E-cadherin increased. CONCLUSIONS: BP-1-102 is a novel drug with a great potential in pituitary tumors. Given their important roles in the growth of pituitary adenomas, STAT3 and Fascin-1 can be used as new treatment targets.


Assuntos
Adenoma/metabolismo , Proliferação de Células , Proteínas dos Microfilamentos/metabolismo , Neoplasias Hipofisárias/metabolismo , Receptores Odorantes/metabolismo , Fator de Transcrição STAT3/metabolismo , Ácidos Aminossalicílicos/administração & dosagem , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/administração & dosagem
18.
Nanoscale Adv ; 3(2): 604-610, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36131743

RESUMO

For overall water electrolysis, the hydrogen evolution reaction (HER) is severely limited by the sluggish kinetics of the anodic oxygen evolution reaction (OER). Therefore, replacing the OER with a more favorable anodic oxidation reaction with remarkable kinetics is of paramount significance, especially the one that can produce value-added chemicals. Moreover, time-saving and cost-effective strategies for the fabrication of electrodes are helpful for the wide application of electrolysis. Herein, thermodynamically more favorable iodide electrooxidation over Ni doped Co(OH)2 nanosheet arrays (NSAs) in alkaline solution is presented as the alternative to the OER to boost the HER. And the active species are determined to be the reverse redox of the Co(iv)/Co(iii) couple. Remarkably, a negative shift of voltage of 320 mV is observed at a current density of 10 mA cm-2 after using iodide electrolysis to replace ordinary water splitting. The synthetic strategy and iodide oxidation in this work expand the application of Co-based materials in the field of energy-saving hydrogen production.

19.
ACS Biomater Sci Eng ; 7(10): 4999-5006, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34550683

RESUMO

Iron-based metal-organic frameworks (MOFs) have been reported to have great potential for encapsulating doxorubicin hydrochloride (DOX), which is a frequently used anthracycline anticancer drug. However, developing a facile approach to realize high loading capacity and efficiency as well as controlled release of DOX in MOFs remains a huge challenge. Herein, we synthesized water-stable MIL-101(Fe)-C4H4 through a microwave-assisted method. It was found the nano-MOFs acted as nanosponges when soaked in a DOX alkaline aqueous solution with a loading capacity experimentally up to 24.5 wt %, while maintaininga loading efficiency as high as 98%. The mechanism of the interaction between DOX and nanoMOFs was investigated by absorption spectra and density functional theory (DFT) calculations, which revealed that the deprotonated DOX was electrostatically adsorbed to the unsaturated Fe3OCl(COO)6·H2O (named Fe3 trimers). In addition, the as-designed poly(ethylene glycol-co-propylene glycol) (F127) modified nanoparticles (F127-DOX-MIL) could be decomposed under the stimulation of glutathione (GSH) and ATP. As a result, DOX and Fe(III) ions were released, and they could undergo a Fenton-like reaction with the endogenous H2O2 to generate the highly toxic hydroxyl radical (·OH). The in vitro experiments indicated that F127-DOX-MIL could cause remarkable Hela cells inhibition through chemotherapy and chemodynamic therapy. Our study provides a new strategy to design a GSH/ATP-responsive drug-delivery nanosystem for chemo/chemodynamic therapy.


Assuntos
Doxorrubicina , Estruturas Metalorgânicas , Compostos Férricos , Células HeLa , Humanos , Peróxido de Hidrogênio
20.
Angew Chem Int Ed Engl ; 60(47): 25068-25074, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34529885

RESUMO

Porous materials for C2 H2 /CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low-cost, and easily scaled-up aluminum MOF (CAU-10-H) for highly efficient C2 H2 /CO2 separation. The suitable pore confinement in CAU-10-H can not only provide multipoint binding interactions with C2 H2 but also enable the dense packing of C2 H2 inside the pores. This material exhibits one of the highest C2 H2 storage densities of 392 g L-1 and highly selective adsorption of C2 H2 over CO2 at ambient conditions, achieved by a low C2 H2 adsorption enthalpy (27 kJ mol-1 ). Breakthrough experiments confirm its exceptional separation performance for C2 H2 /CO2 mixtures, affording both large C2 H2 uptake of 3.3 mmol g-1 and high separation factor of 3.4. CAU-10-H achieves the benchmark balance between separation performance, stability, and cost for C2 H2 /CO2 separation.

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