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1.
Adv Mater ; 36(26): e2401878, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602717

RESUMO

2D conjugated metal-organic frameworks (2D c-MOFs) have garnered significant attention as promising electroactive materials for energy storage. However, their further applications are hindered by low capacity, limited cycling life, and underutilization of the active sites. Herein, Cu-TBA (TBA = octahydroxyltetrabenzoanthracene) with large conjugation units (narrow energy gap) and a unique rhombus topology is introduced as the cathode material for sodium-ion batteries (SIBs). Notably, Cu-TBA with a rhombus topology exhibits a high specific surface area (613 m2 g-1) and metallic band structure. Additionally, Cu-TBA outperforms its hexagonal counterpart, Cu-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxyltriphenylene), demonstrating superior reversible capacity (153.6 mAh g-1 at 50 mA g-1) and outstanding cyclability with minimal capacity decay even after 3000 cycles at 1 A g-1. This work elucidates a new strategy to enhance the electrochemical performance of 2D c-MOFs cathode materials by narrowing the energy gap of organic linkers, effectively expanding the utilization of 2D c-MOFs for SIBs.

2.
Angew Chem Int Ed Engl ; : e202405168, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668683

RESUMO

2D conjugated metal-organic frameworks (2D c-MOFs) with large pore sizes and high surface areas are advantageous for adsorbing iodine species to enhance the electrochemical performance of aqueous dual-ion batteries (ADIBs). However, most of the reported 2D c-MOFs feature microporous structures, with few examples exhibiting mesoporous characteristics. Herein, we developed two mesoporous 2D c-MOFs, namely PA-TAPA-Cu-MOF and PA-PyTTA-Cu-MOF, using newly designed arylimide based multitopic catechol ligands (6OH-PA-TAPA and 8OH-PA-PyTTA). Notably, PA-TAPA-Cu-MOF exhibits the largest pore sizes (3.9 nm) among all reported 2D c-MOFs. Furthermore, we demonstrated that these 2D c-MOFs can serve as promising cathode host materials for polyiodides in ADIBs for the first time. The incorporation of triphenylamine moieties in PA-TAPA-Cu-MOF resulted in a higher specific capacity (423.4 mAh g-1 after 100 cycles at 1.0 A g-1) and superior cycling performance, retaining 96 % capacity over 1000 cycles at 10 A g-1 compared to PA-PyTTA-Cu-MOF. Our comparative analysis revealed that the increased number of N anchoring sites and larger pore size in PA-TAPA-Cu-MOF facilitate efficient anchoring and conversion of I3 -, as supported by spectroscopic electrochemistry and density functional theory calculations.

3.
Angew Chem Int Ed Engl ; 63(25): e202405239, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634305

RESUMO

The evolution of two-dimensional conjugated metal-organic frameworks (2D c-MOFs) provides a significant prospect for researching the next generation of green and advanced energy storage systems (ESSs). Especially, conjugation and topology engineering serve as an irreplaceable character in adjusting the electrochemical properties of ESSs. Herein, we proposed a novel strategy using conjugation and topology engineering to demonstrate the application of 2D c-MOFs in robust potassium-ion batteries (PIBs) for the first time. By comparing 2D c-MOFs with the rhombus/kagome structure as well as three/four-arm core, the rhombus structure (sql-Cu-TBA-MOF) cathode for PIBs can display the impressive electrochemical performance, including a high specific discharge capacity of 178.4 mAh g-1 (at 0.2 A g-1) and a well long-term cycle stability of more than 9,000 (at 10.0 A g-1). Moreover, full PIBs (FPIBs) are constructed by pairing sql-Cu-TBA-MOF cathode with dipotassium terephthalate (KTP) anode, which delivers a high reversible discharge specific capacity of 146.6 mAh g-1 (at 0.1 A g-1) and great practical application prospect. These findings provide reasonable implications for the design of 2D c-MOFs from the perspective of conjugation and topology engineering for advanced energy storage systems.

4.
J Colloid Interface Sci ; 663: 656-664, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430835

RESUMO

Ion concentration and mobility are tightly associated with the ionic conductance of polymer electrolytes in solid-state lithium batteries. However, the anions involved in the movement are irrelevant to energy generation and cause uncontrolled dendritic growth and concentration polarization. In the current study, we proposed the strategy of using a bipolar organic molecule as the anion/cation-hosting cathode to expand the active charge carriers of polymer electrolytes. As a proof-of-concept demonstration of the novel strategy, a bipolar phthalocyanine derivative (2,3,9,10,16,17,23,24-octamethoxyphthalocyaninato) Ni(II) (NiPc-(OH)8) that could successively store anions and cations was used as the cathode hosting material in quasi-solid-state dual-ion batteries (QSSDIBs). Interestingly, peripheral polyhydroxyl substituents could build a compatible interface with poly(vinylidene fluoride-hexafluoro propylene-based gel polymer electrolytes (PVDF-HFP). As expected, NiPc-(OH)8 displays a high specific capacity of 248.2 mAh/g (at 50 mA g-1) and improved cyclic stability compared with that in liquid electrolyte. This study provides a solution to the issue of anion migration and could open another way to build high-performance QSSDIBs.

5.
Adv Mater ; 36(6): e2305605, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37566706

RESUMO

Potassium-ion batteries (PIBs) are gradually gaining attention owing to their natural abundance, excellent security, and high energy density. However, developing excellent organic cathode materials for PIBs to overcome the poor cycling stability and slow kinetics caused by the large radii of K+ ions is challenging. This study demonstrates for the first time the application of a hexaazanonaphthalene (HATN)-based 2D π-d conjugated metal-organic framework (2D c-MOF) with dual-active centers (Cu-HATNH) and integrates Cu-HATNH with carbon nanotubes (Cu-HATNH@CNT) as the cathode material for PIBs. Owing to this systematic module integration and more exposed active sites with high utilization, Cu-HATNH@CNT exhibits a high initial capacity (317.5 mA h g-1 at 0.1 A g-1 ), excellent long-term cycling stability (capacity retention of 96.8% at 5 A g-1 after 2200 cycles), and outstanding rate capacity (147.1 mA h g-1 at 10 A g-1 ). The reaction mechanism and performance are determined by combining experimental characterization and density functional theory calculations. This contribution provides new opportunities for designing high-performance 2D c-MOF cathodes with multiple active sites for PIBs.

6.
Angew Chem Int Ed Engl ; 63(3): e202314411, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37897193

RESUMO

In the emerging aqueous zinc ion batteries (AZIBs), proton (H+ ) with the smallest molar mass and fast (de)coordination kinetics is considered as the most ideal charge carrier compared with Zn2+ counterpart, however, searching for new hosting materials for H+ storage is still at its infancy. Herein, redox-active hydrogen-bonded organic frameworks (HOFs) assembled from diaminotriazine moiety decorated hexaazatrinnphthalene (HOF-HATN) are for the first time developed as the stable cathode hosting material for boosting H+ storage in AZIBs. The unique integration of hydrogen-bonding networks and strong π-π stacking endow it rapid Grotthuss proton conduction, stable supramolecular structure and inclined H+ storage. As a consequence, HOF-HATN displays a high capacity (320 mAh g-1 at 0.05 A g-1 ) and robust cyclability of (>10000 cycles at 5 A g-1 ) based on three-step cation coordination storage. These findings get insight into the proton transport and storage behavior in HOFs and provide the molecular engineering strategy for constructing well-defined cathode hosting materials for rechargeable aqueous batteries.

7.
Cell Chem Biol ; 31(3): 428-445, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-37802076

RESUMO

Recent years have seen a remarkable growth in the field of protein-based medical treatments. Nevertheless, concerns have arisen regarding the cytotoxicity limitations, low affinity, potential immunogenicity, low stability, and challenges to modify these proteins. To overcome these obstacles, proximity-induced chemistry has emerged as a next-generation strategy for advancing protein therapeutics. This method allows site-specific modification of proteins with therapeutic agents, improving their effectiveness without extensive engineering. In addition, this innovative approach enables spatial control of the reaction based on proximity, facilitating the formation of irreversible covalent bonds between therapeutic proteins and their targets. This capability becomes particularly valuable in addressing challenges such as the low affinity frequently encountered between therapeutic proteins and their targets, as well as the limited availability of small molecules for specific protein targets. As a result, proximity-induced chemistry is reshaping the field of protein drug preparation and propelling the revolution in novel protein therapeutics.


Assuntos
Proteínas
8.
J Colloid Interface Sci ; 649: 159-165, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37348335

RESUMO

High-performance organic small-molecule electrode materials are troubled with their high solubility in liquid electrolytes. The construction of quasi-solid-state lithium organic batteries (LOBs) using gel polymer electrolytes with high mechanical properties, compromised ionic conductivity, high safety, and eco-friendly is an effective way to inhibit the dissolution of active materials. Herein, two hexaazatriphenylene (HATN)-based organic cathode materials (HATNA-6OCH3 and HATNA-6OH) are synthesized and then matched with polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP)-based gel polymer electrolytes to construct quasi-solid-state LOBs. Thanks to the enhanced interfacial compatibility between organic cathode material and gel polymer electrolyte, HATNA-6OH with compatible hydroxyl group shows the enhanced electrochemical properties compared with HATNA-6OCH3. Further, the electrochemical performance is improved when HATNA-6OH is combined with a gel polymer electrolyte modified with a succinonitrile (SN) plasticizer (GPE-0.4SN), including a high specific capacity of 153.3 mAh g-1 at 50 mA g-1 and a good reversible capacity of 88 mAh g-1 after 100 cycles at 200 mA g-1. In addition, the good electrochemical properties and lithium-ion storage mechanism of HATNA-6OH have been elucidated using density functional theory (DFT) and spectral characterizations.

9.
Small ; 19(35): e2301578, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37105762

RESUMO

The development of coordination polymers with π-d conjugation (CCPs) provides ide prospects for exploring the next generation of environmental-friendliness energy storage systems. Herein, the synthesis, experimental characterizations, and Na-ion storage mechanism of π-d CCPs with multiple-active sites are reported, which use quinone-fused aza-phenazine (AP) and aza-phenazin (AP) as the organic ligands coordinated with the metal center (Ni2+ ). Among them, NiQAP as the cathode material exhibits impressive electrochemical properties applied in sodium-ion batteries (SIBs), including the high initial/stable discharge specific capacities (180.0/225.6 mAh g-1 ) at 0.05 A g-1 , a long-term cycle stability up to 10,000 cycles at 1.0 A g-1 with a high reversible capacity of 100.1 mAh g-1 , and good rate capability of 99.6 mAh g-1 even at 5.0 A g-1 . Moreover, the Na-ion storage mechanism of NiQAP is also performed by the density functional theory (DFT) calculation, showing multiple-active sites of C≐O and C≐N (in the quinone and phenazine structure) and NiO4 (in the coordination unit) for Na-ion storage. These results highlight the importance of organic electrode material with the coordination units and provide a foundation for further studying the CCPs with multiple active sites for energy storage systems.

10.
Opt Express ; 30(26): 46722-46733, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558617

RESUMO

With the developments of the tunable laser source (TLS), there are increasing demands for high-resolution dynamic wavelength calibration in recent years. Considering mutual constraints between wide measurement range and high calibration resolution, we propose a dynamic wavelength calibration method based on an auxiliary Mach-Zehnder interferometer (MZI) and the synchrosqueezed wavelet transform (SSWT). Our proposed method can achieve a calibration resolution of 5 fm and a tuning range of 10 nm. Moreover, the measurement range and spatial resolution of the optical frequency domain reflectometer (OFDR) system are improved to ∼80 m and ∼mm, respectively. Our proposed approach can substantially reduce the subtle spectrum distortion (tens of fm) in coherent optical spectrum analyzer (COSA) systems.

11.
Environ Pollut ; 295: 118707, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34923062

RESUMO

Biochar application into paddy is an improved strategy for addressing methane (CH4) stimulation of straw biomass incorporation. Whereas, the differentiative patterns and mechanisms on CH4 emission of straw biomass and biochar after long years still need to be disentangled. Considering economic feasibility, a seven-year of field experiment was conducted to explore the long-term CH4 mitigation effect of annual low-rate biochar incorporation (RSC, 2.8 t ha-1), with annual rice straw incorporation (RS, 8 t ha-1) and control (CK, with no biochar or rice straw amendment incorporation) as a comparation. Results showed that RSC mitigated CH4 emission while RS stimulated CH4 significantly (p < 0.05) and stably over 7 experimental years compared with CK. RSC mitigated 14.8-46.7% of CH4 emission compared with CK. In comparison to RSC, RS increased 111-950.5% of CH4 emission during 7 field experimental years. On the 7th field experimental year, pH was significantly increased both in RS and RSC treatment (p < 0.05). RSC significantly (p < 0.05) increased soil nitrate (NO3--N) compared with RS while RS significantly (p < 0.05) increased dissolved carbon (DOC) compared to RSC. Soil NO3--N inhibition on methanogens and promotion on methanotrophs activities were verified by laboratory experiment, while soil pH and DOC mainly promoted methanogens abundance. Significantly (p < 0.05) increased DOC and soil pH enhanced methanogens growth and stimulated CH4 emission in RS treatment. Higher soil NO3--N content in RSC than CK and RS contributed to CH4 mitigation. Soil NO3--N and DOC were identified as the key factors differentiating CH4 emission patterns of RS and RSC in 2019. Collectively, soil NO3--N impacts on CH4 flux provide new ideas for prolonged effect of biochar amendment on CH4 mitigation after years.


Assuntos
Óxido Nitroso , Oryza , Agricultura , Carvão Vegetal , Metano , Óxido Nitroso/análise , Solo
12.
RSC Adv ; 11(14): 7913-7924, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35423344

RESUMO

A new Prussian blue analog (PBA) that contains three metal elements and has peroxidase-like activity was synthesized by a simple method. Then, AgNO3 solution was added slowly to the PBA solution under continuous stirring. We found that this synthesis method could be used to prepare other PBAs, and that the anchoring of Ag+ on the surface of PBA could enhance the peroxidase-like activity of the material, suggesting potential applications for the Ag+-decorated Prussian blue analog (Ag-PBA) in traditional Chinese medicine. Ag-PBA is a new type of multi-metal cubic nano-enzyme that exhibits good stability and excellent peroxidase-like activity; as such, it could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 and Ag-PBA. We then developed a new method to measure the content of antioxidant substances in Chinese herbs by using the excellent peroxidase-like activity of Ag-PBA. Using the Chinese herb Lycium ruthenicum Murr. as a model compound, we measured the content of the antioxidant substances in Lycium ruthenicum Murr. by this new method. After optimization of reaction temperature, concentrations of TMB and H2O2, and reaction time, the content of the antioxidant substances was measured and calculated in comparison with anthocyanidin standards. The results of the Ag-PBA method and the classical DPPH method were compared by a paired t-test, with no statistically significant difference found between the methods. Hence, these two methods can be used interchangeably, although the Ag-PBA method had the advantages of simplicity, rapidness, and good stability. Moreover, the Ag-PBA method has a low limit of quantification and a shorter reaction time, which are improvements on the DPPH method, and it is not necessary to avoid light. Therefore, we anticipate that the Ag-PBA method may be used widely for the measurement of the content of antioxidant substances in Chinese herbs.

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