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1.
Sci Rep ; 14(1): 6466, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499593

RESUMO

Organometal halide perovskite solar cells have reached a high power conversion efficiency of up to 25.8% but suffered from poor long-term stability against environmental factors such as ultraviolet irradiation and humidity of the environment. Herein, two different multifunctional transparent coatings containing AZO and ZnO porous UV light absorbers were employed on the front of the PSCs. This strategy is designed to improve the long-term stability of PSCs against UV irradiation. Moreover, the provided coatings exhibit two additional roles, including self-cleaning and high wear resistance. In this regard, AZO coating showed higher wear resistance compared to the ZnO coating. The photocatalytic self-cleaning properties of these prepared coatings make them stable against environmental pollutants. Furthermore, appropriate mechanical properties such as high hardness and low coefficient of friction that leads to high resistance against wear are other features of these coatings. The devices with AZO/Glass/FTO/meso-TiO2/Perovskite/spiro/Au and ZnO/Glass/FTO/meso-TiO2/Perovskite/spiro/Au configurations maintained 40% and 30% of their initial performance for 100 h during 11 days (9 h per day) against the UV light with the high intensity of 50 mW cm-2 which is due to higher absorption of AZO compared with ZnO in the ultraviolet region. Since AZO has a higher light transmission in the visible region in comparison to ZnO, perovskite cells with AZO protective layers have higher efficiency than perovskite cells with ZnO layers. It is worth noting that the mentioned features make these coatings usable for cover glass in all types of solar cells.

2.
Sci Rep ; 14(1): 1451, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228770

RESUMO

In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42-), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42- was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly.

3.
RSC Adv ; 13(50): 35639-35647, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38077985

RESUMO

In this study, a lactose fatty acid ester was enzymatically synthesised using immobilized Candida rugosa lipase (CRL). Its anticancer property against K562 leukemia and HeLa cancer cells was carefully investigated. In the first step, a de novo strategy was applied to encapsulate CRL into a microporous zeolite imidazolate framework called ZIF-8. Various characterization techniques including powder X-ray diffraction, Fourier transform infrared spectroscopy, N2 adsorption-desorption, field-emission scanning electron microscopy and thermogravimetric analysis were used to prove the successful encapsulation of CRL molecules during the formation of ZIF-8 crystals with an enzyme loading of 98% of initial CRL. The effect of various factors such as pH and temperature, affecting the enzymatic activity and reusability of the CRL@ZIF-8 composite were assessed against the free enzyme. Additionally, enzyme catalysis parameters, such as Km and Vmax, were also assessed. The obtained biocatalyst showed excellent activity in a wide pH range of 2-9 and a temperature range of 30-60 °C. According to the experimental results, the CRL@ZIF-8 composite maintained about 63% of its initial activity after 6 cycles of use. In the next step, the synthesized catalyst was applied for the synthesis of lactose caprate via enzymatic esterification of lactose with capric acid. Further experiments were performed to obtain the cytotoxicity profile of the new derivative. The growth inhibitory effect of the produced lactose caprate on K562 leukemia and HeLa cancer cells determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed its potential anticancer effects against both cell lines (IC50, 49.6 and 57.2 µg mL-1). Our results indicate that lactose caprate might be a promising candidate for further studies on K562 leukemia and HeLa cancer cells owing to its possible therapeutic usefulness.

4.
RSC Adv ; 13(44): 31213-31223, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37886018

RESUMO

Aminopropyl-1,3,5-triazine-2,4-diphosphonium tetrachloroferrate immobilized on halloysite nanotubes [(APTDP)(FeCl4)2@HNT] was prepared and fully characterized using different techniques such as FT-IR, thermogravimetric analysis (TGA), SEM/EDX, elemental mapping, TEM, ICP-OES, and elemental analysis (EA). This nanocatalyst was found to be highly effective for synthesis of various benzothiazole derivatives in excellent yields under solvent-free conditions. Furthermore, bis- and tris-benzothiazoles were smoothly synthesized from dinitrile and trinitrile in the presence of this catalytic system. High yields and purity, easy work up procedure, high catalytic activity (high TON and TOF) and easy recovery and reusability of the catalyst make this method a useful and important addition to the present methodologies for preparation of these vital heterocyclic compounds.

5.
J Colloid Interface Sci ; 648: 78-89, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295372

RESUMO

Two novel MOF- ethyl cellulose (EC)- based nanocomposites have been designed and synthesized in water by electrospinning and applied for adsorption of congo red (CR) in water. Nano- Zeolitic Imidazolate Framework-67 (ZIF-67), and Materials of Institute Lavoisier (MIL-88A) were synthesized in aqueous solutions by a green method. To enhance the dye adsorption capacity and stability of MOFs, they have been incorporated into EC nanofiber to prepare composite adsorbents. The performance of both composites in the absorption of CR, a common pollutant in some industrial wastewaters, has then been investigated. Various parameters including initial dye concentration, the dosage of the adsorbent, pH, temperature and contact time were optimized. The results indicated 99.8 and 90.9% adsorption of CR by EC/ZIF-67 and EC/MIL-88A, respectively at pH = 7 and temperature at 25 °C after 50 min. Furthermore, the synthesized composites were separated conveniently and successfully reused five times without significant loss of their adsorption activity. For both composites, the adsorption behavior can be explained by pseudo-second-order kinetics, Intraparticular diffiusion and Elovich models demonstrated that the experimental data well matched to the pseudo-second-order kinetics. Intraparticular diffiusion model showed that the adsorption of CR on EC/ZIF-67 and EC/MIL-88a took place in one and two steps, respectively. Freundlich isotherm models and thermodynamic analysis indicated exothermic and spontaneous adsorption.

6.
ACS Omega ; 8(20): 17809-17818, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37251154

RESUMO

There is a growing concern that the increasing concentration of CO2 in the atmosphere contributes to a potential negative impact on global climate change. To deal with this problem, developing a set of innovative, practical technologies is essential. In the present study, maximizing the CO2 utilization and precipitation as CaCO3 was evaluated. In this manner, bovine carbonic anhydrase (BCA) was embedded into the microporous zeolite imidazolate framework, ZIF-8, via physical absorption and encapsulation. Running as crystal seeds, these nanocomposites (enzyme-embedded MOFs) were in situ grown on the cross-linked electrospun polyvinyl alcohol (CPVA). The prepared composites displayed much higher stability against denaturants, high temperatures, and acidic media than free BCA, and BCA immobilized into or on ZIF-8. During 37 days of storage period study, BCA@ZIF-8/CPVA and BCA/ZIF-8/CPVA maintained more than 99 and 75% of their initial activity, respectively. The composition of BCA@ZIF-8 and BCA/ZIF-8 with CPVA improved stability for consecutive usage in recovery reactions, recycling easiness, and greater control over the catalytic process. The amounts of calcium carbonate obtained by one mg each of fresh BCA@ZIF-8/CPVA and BCA/ZIF-8/CPVA were 55.45 and 49.15 mg, respectively. The precipitated calcium carbonate by BCA@ZIF-8/CPVA reached 64.8% of the initial run, while this amount was 43.6% for BCA/ZIF-8/CPVA after eight cycles. These results indicated that the BCA@ZIF-8/CPVA and BCA/ZIF-8/CPVA fibers could be efficiently applied to CO2 sequestration.

7.
ACS Omega ; 8(18): 15883-15895, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179652

RESUMO

The current study deals with the synthesis and characterization of a novel catalyst made from diphenhydramine hydrochloride and CuCl ([HDPH]Cl-CuCl). The prepared catalyst was thoroughly characterized using various techniques, such as 1H NMR, Fourier transform-infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis and derivative thermogravimetry. More importantly, the observed hydrogen bond between the components was proven experimentally. The activity of this catalyst was checked in the preparation of some new derivatives of tetrahydrocinnolin-5(1H)-ones via a multicomponent reaction between dimedone, aromatic aldehydes, and aryl/alkyl hydrazines in ethanol as a green solvent. Also, for the first time, this new homogeneous catalytic system was effectively used for the preparation of unsymmetric tetrahydrocinnolin-5(1H)-one derivatives as well as mono- and bis-tetrahydrocinnolin-5(1H)-ones from two different aryl aldehydes and dialdehydes, respectively. The effectiveness of this catalyst was further confirmed by the preparation of compounds containing both tetrahydrocinnolin-5(1H)-one and benzimidazole moieties from dialdehydes. The one-pot operation, mild conditions, rapid reaction, and high atom economy, along with the recyclability and reusability of the catalyst, are other notable features of this approach.

8.
Sci Rep ; 13(1): 6368, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076530

RESUMO

Inorganic hole-transport materials (HTMs) such as copper indium disulfide (CIS) have been applied in perovskite solar cells (PSCs) to improve the poor stability of the conventional Spiro-based PSCs. However, CIS-PSCs' main drawback is their lower efficiency than Spiro-PSCs. In this work, copolymer-templated TiO2 (CT-TiO2) structures have been used as an electron transfer layer (ETL) to improve the photocurrent density and efficiency of CIS-PSCs. Compared to the conventional random porous TiO2 ETLs, copolymer-templated TiO2 ETLs with a lower refractive index improve the transmittance of input light into the cell and therefore enhance the photovoltaic performance. Interestingly, a large number of surface hydroxyl groups on the CT-TiO2 induce a self-healing effect in perovskite. Thus, they provide superior stability in CIS-PSC. The fabricated CIS-PSC presents a conversion efficiency of 11.08% (Jsc = 23.35 mA/cm2, Voc = 0.995, and FF = 0.477) with a device area of 0.09 cm2 under 100 mW/cm2. Moreover, these unsealed CIS-PSCs retained 100% of their performance after aging tests for 90 days under ambient conditions and even increased from 11.08 to 11.27 over time due to self-healing properties.

9.
RSC Adv ; 12(34): 22180-22187, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-36043092

RESUMO

An efficient and reusable catalyst, which is 3-(propylthio)propane-1-sulfonic acid immobillized on functionalized magnetic nanoparticles [PTPSA@SiO2-Fe3O4], has been synthesized. For the first time, it is highlighted under solvent-free conditions for the catalytic activity in multicomponent synthesis of dihydrotetrazolo[1,5-a]pyrimidines, dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylates and tetrahydrotetrazolo[5,1-b]quinazolinones. The structure of the catalyst was well confirmed by characterization techniques, such as FT-IR, TGA, SEM-EDX, elemental mapping, TEM, VSM and elemental analysis. Besides, this unique catalyst was found to be effectual up to six cycles, which made it spotlighted. Recyclability of catalyst, excellent yield of the products, short reaction time and clean reaction profile are the advantages of the present protocol.

10.
RSC Adv ; 12(10): 5971-5977, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35424559

RESUMO

The self-assembly approach was used for amine decoration of core/shell Fe3O4@Au with 4-aminothiophenol. This structure was used for covalent immobilization of lipase using a Ugi 4-component reaction. The amine group on the structure and carboxylic group from lipase can react in the Ugi reaction and a firm and stable covalent bond is created between enzyme and support. The synthesized structure was fully characterized and its activity was explored in different situations. The results showed the pH and temperature stability of immobilized lipase compared to free lipase in a wide range of pH and temperature. Also after 60 days, it showed excellent activity while residual activity for the free enzyme was only 10%. The synthesized structure was conveniently separated using an external magnetic field and reused 6 times without losing the activity of the immobilized enzyme.

11.
Dalton Trans ; 50(30): 10567-10579, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34263897

RESUMO

Environmental concerns, particularly global warming, represent serious threats to public health globally. Metal-organic frameworks (MOFs) are innovative materials with prominent features such as ultrahigh surface area, high porosity and tunable cavities, which make them unique materials both in adsorption of carbon dioxide and catalysis. The design of new nanocomposites by using metal-organic frameworks as building materials has received broad attention recently. Here, nanocrystals of two unique MOF structures (UiO-66 and ZIF-67) were incorporated into electrospun polyvinyl alcohol (PVA) and polystyrene (PS) fibers (noted as MOFibers) by an ex situ method, to transform non-toxic, abundant, economical and renewable CO2 gas to cyclic carbonates in a solvent-free medium. In order to improve the composites' performance, different electrospinning parameters, including applied voltage, flow rate, collection distance, PVA and PS weight fraction in solution, and MOF weight fraction relative to the polymer, were intensively investigated. The synthesized samples were characterized by multiple techniques, such as FTIR, XRD, SEM, UV-vis and TGA, as well as N2 and CO2 adsorption measurement. It was found that all of the composites show properties combining the advantages of MOFs and polymers, such as thermal, chemical, and mechanical stability, structural flexibility, lightweight, adsorption performance and catalytic properties. Additionally, all systems were environment-friendly and the PVA/MOF fibers were easily separated and recycled for consecutive cycles.

12.
RSC Adv ; 11(20): 11976-11983, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35423765

RESUMO

1,1'-(6-(Propyl amino)-1,3,5-triazine-2,4-diyl)bis(pyridinium) hydrogen sulfate immobillized on halloysite nanotubes [(PATDBP)(HSO4)2@HNT] as a solid acid nanocatalyst was successfully synthesized and characterized by various analysis techniques such as FT-IR, TGA, SEM/EDX, elemental mapping, TEM and elemental analysis. This catalyst was found to be highly efficient for the convenient synthesis of naphthopyranopyrimidine derivatives through a one-pot three-component reaction of ß-naphthol, aldehydes and N,N-dimethylbarbituric acid in excellent yields under solvent-free conditions. Furthermore, the catalyst could be recovered and reused five times without any notable loss of its activity.

13.
RSC Adv ; 10(55): 33137-33147, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35515057

RESUMO

A novel and unique platform was prepared based on a dendrimer containing thiol groups supported on nanosilica (nSTDP), and ultrafine platinum nanoparticles were synthesized and immobilized on the thiol decorated branches of nSTPD. The new catalyst, (Ptnp@nSTDP), was characterized by different techniques such as FE-SEM, TEM, ICP, XPS and DR UV-vis. This heterogeneous catalyst presented an outstanding performance for the synthesis of benzimidazole and benzothiazole derivatives through a reaction between benzyl alcohol derivatives and 2-aminothiophenol or 1,2-phenylenediamine. No requirement for the pre-reduction of catalysts and using water as a green solvent make it an individual catalyst for these reactions. Furthermore, the catalyst can be easily recovered and reused five consecutive times in the production of benzimidazoles and benzothiazoles without significant leaching of Pt and loss of its activity which illustrated the chemical stability of the catalyst during the reaction.

14.
RSC Adv ; 10(36): 21198-21205, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35518753

RESUMO

Dendrimers are of great interest due to their special structural topology and chemical versatility. Owing to their properties, dendrimers have found practical applications in catalytic processes as efficient nanoreactors. Therefore, we herein report an environmentally attractive strategy and highly efficient route for the synthesis of a wide variety of diaryl sulfides using palladium nanoparticles immobilized on a nano-silica triazine dendritic polymer (Pdnp-nSTDP) as a nanoreactor. In this manner, different diaryl or aryl heteroaryl sulfides and bis(aryl/heteroarylthio)benzene/anthracene/pyridine derivatives were prepared via C-S cross-coupling reactions of aryl halides with diaryl/diheteroaryl disulfides under thermal conditions and microwave irradiation. The catalyst could be easily recovered and reused several times without any significant loss of its activity.

15.
ACS Appl Bio Mater ; 3(12): 8414-8426, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35019613

RESUMO

To expand the field of nanomaterial and engineering of enzyme in eco-friendly processes, gold mesoflower (Au-MF) nanostructure was applied for preparation of three series of immobilized lipase (Au-MF/SAM 1-3) through biofunctionalization of surface by Ugi multicomponent reaction. The synthesized Au-MF/SAM 1-3/lipase as unique biocatalysts was confirmed by different analytical tools and techniques. Compared to the free lipase, the Au-MF/SAM 1-3/lipase showed more stability at high temperature and pH. Also, these biocatalysts showed high storage stability and reusability after 2 months and eight cycles, respectively. Moreover, the kinetic behavior was investigated and the results showed a minimal impairment of catalytic activity of immobilized lipase. The kinetic constants of the immobilized lipase, Au-MF/SAM 2/lipase, are Km = 0.37 mM, Vmax = 0.22 mM min-1, and kcat = 154 min-1. The immobilized lipase showed smaller activation energy (Ea) than that of free enzyme, indicating that the immobilized enzyme is less sensitive to temperature. In the following, the biodiesel production from palmitic acid was studied in the presence of Au-MF/SAM 2/lipase as an efficient biocatalyst. The influence of different reaction parameters such as temperature, molar ratio of alcohol to palmitic acid, water content, and lipase amount was deeply investigated.

17.
RSC Adv ; 9(49): 28460-28469, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-35529640

RESUMO

In this work, maximizing the utilization of CO2 and its precipitation as CaCO3 by using immobilized bovine carbonic anhydrase (BCA) was evaluated. In this way, selection of suitable carriers which have a gas adsorption function would enhance the CO2 sequestration efficiency of the carbonic anhydrase (CA). So a metal-organic framework (MOF), an excellent material for gas adsorption and enzyme immobilization was used. In this manner, BCA was encapsulated into the microporous zeolite imidazolate framework, ZIF-8, for the first time, using a bottle-around-a-ship method. Systematic characterization including powder X-ray diffraction (PXRD), UV-vis, and Fourier transform infrared (FT-IR) spectroscopies, BET, field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDX) confirmed that the entrapment of BCA molecules was successfully achieved during the crystal growth of ZIF-8 with an enzyme loading of ca. 100 ± 1.2 mg g-1 of BCA-ZIF-8. Optimization of the matrix for increasing the stability of the enzyme in an encapsulated form is the main aim of the present study. The de novo approach was proposed because this method provides better enzyme protection from degradation, minimizes enzyme leaching and enables multiple reuse. Then, the influence of different parameters, including pH, temperature, storage and reusability, was evaluated for enzyme@MOF composites versus free enzymes. The prepared biocatalyst exhibited outstanding activity in a wide pH and temperature range and demonstrates high storage stability up to 37 days. This efficient and simple association procedure seems well-adapted to produce an enzymatic bio-catalyst for biocatalytic hydration of CO2. The FT-IR analysis revealed that the structure of BCA was well maintained during the encapsulation process. The thermal stability and reusability of the BCA-ZIF-8 increased noticeably due to the structural rigidity and confinement of the ZIF-8 scaffolds. These two parameters are very important for practical applications.

18.
J Org Chem ; 83(23): 14743-14750, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30398359

RESUMO

This report explains an efficient method for synthesis of an array of quinolines via the reaction of 2-aminoaryl ketones with terminal and internal alkynes in the presence of propylphosphonium tetrachloroindate ionic liquid supported on nanosilica (PPInCl-nSiO2) as a heterogeneous and reusable catalyst under solvent-free conditions. Inspired by this catalytic system, the first easy one-step synthesis of symmetric and unsymmetric pyrido[3,2- g or 2,3- g]quinolines was investigated through the reaction of diaroylphenylenediamines with one alkyne or two different alkynes.

19.
ACS Comb Sci ; 20(6): 358-365, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29689156

RESUMO

A versatile and straightforward synthetic strategy for the construction of new tetrasubstituted 1,3-diazinones is described. The procedure is based on CsF-catalyzed, microwave-assisted, ring transformation reaction of arylidene azlactones with amidines. Moreover, this technique provides diversified trans- N-(6-oxo-1,4,5,6-tetrahydropyrimidin-5-yl)benzamides with a good antimicrobial activity.


Assuntos
Antibacterianos/síntese química , Benzamidas/síntese química , Césio/química , Fluoretos/química , Oxazolona/análogos & derivados , Oxazolona/química , Pirimidinas/síntese química , Bacillus subtilis/efeitos dos fármacos , Catálise , Escherichia coli/efeitos dos fármacos , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo
20.
ACS Comb Sci ; 20(1): 19-25, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29215873

RESUMO

In this Research Article, we report an efficient synthesis of 1,3-dimethyl-5-aryl-7-(pyridine-3(2)(4)-yl)pyrimidine-2,4(1H,3H)-diones via a three-component reaction of aryl aldehydes, 1,3-dimethyl-6-aminouracil and carbonitriles in the presences of triazine diphosphonium hydrogen sulfate ionic liquid supported on functionalized nanosilica (APTADPHS-nSiO2) as a reusable catalyst under microwave irradiation and solvent-free conditions. The bis-derivatives of pyridine-pyrimidines were also efficiently prepared from dialdehydes and dinitriles. In addition, 3-methyl-1H-pyrazole-5-amine was used successfully instead of 1,3-dimethyl-6-aminouracil under the same conditions to afford the corresponding products in high yields. The catalyst can be reused at least five times without any significant loss of its activity. The easy recovery, reusability and excellent activity of the catalyst as well as easy workup are other noteworthy advantages of this method.


Assuntos
Líquidos Iônicos/química , Nanopartículas/química , Piridinas/síntese química , Pirimidinas/síntese química , Dióxido de Silício/química , Catálise , Técnicas de Química Combinatória , Espectroscopia de Ressonância Magnética/métodos , Micro-Ondas , Compostos Organofosforados/química , Propriedades de Superfície , Triazinas/química
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