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1.
Eur J Med Res ; 29(1): 224, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594732

RESUMO

The latest findings in iron metabolism and the newly uncovered process of ferroptosis have paved the way for new potential strategies in anti-leukemia treatments. In the current project, we reviewed and summarized the current role of nanomedicine in the treatment and diagnosis of leukemia through a comparison made between traditional approaches applied in the treatment and diagnosis of leukemia via the existing investigations about the ferroptosis molecular mechanisms involved in various anti-tumor treatments. The application of nanotechnology and other novel technologies may provide a new direction in ferroptosis-driven leukemia therapies. The article explores the potential of targeting ferroptosis, a new form of regulated cell death, as a new therapeutic strategy for leukemia. It discusses the mechanisms of ferroptosis and its role in leukemia and how nanotechnology can enhance the delivery and efficacy of ferroptosis-inducing agents. The article not only highlights the promise of ferroptosis-targeted therapies and nanotechnology in revolutionizing leukemia treatment, but also calls for further research to overcome challenges and fully realize the clinical potential of this innovative approach. Finally, it discusses the challenges and opportunities in clinical applications of ferroptosis.


Assuntos
Ferroptose , Leucemia , Humanos , Nanotecnologia , Leucemia/tratamento farmacológico
2.
Environ Sci Pollut Res Int ; 31(17): 24768-24787, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38523214

RESUMO

An alternative method to conventional synthesis is examined in this review by the use of plant extracts as reducing and capping agents. The use of plant extracts represents an economically viable and environmentally friendly alternative to conventional synthesis. In contrast to previous reviews, this review focuses on the synthesis of nano-compounds utilizing plant extracts, which lack comprehensive reports. In order to synthesize diverse nanostructures, researchers have discovered a sustainable and cost-effective method of harnessing functional groups in plant extracts. Each plant extract is discussed in detail, along with its potential applications, demonstrating the remarkable morphological diversity achieved by using these green synthesis approaches. A reduction and capping agent made from plant extracts is aligned with the principles of green chemistry and offers economic advantages as well as paving the way for industrial applications. In this review, it is discussed the significance of using plant extracts to synthesize nano-compounds, emphasizing their potential to shape the future of nanomaterials in a sustainable and ecologically friendly manner.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/química , Extratos Vegetais/química , Química Verde , Nanoestruturas/química , Plantas/química , Antibacterianos
3.
Environ Sci Pollut Res Int ; 31(14): 21370-21379, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388980

RESUMO

In this article, we present the synthesis of binary CdAl4O7/CdO nanocomposites using green tea extracts and green chemistry methods for high-performance hydrogen storage. The green tea extract contains bioactive compounds (polyphenols) that act as reducing agents, which facilitate the reaction between metal ions and water. By examining the structural and morphological characteristics of the obtained substrates using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR), it was demonstrated that the nanocomposites were successfully synthesized. We evaluated the electrochemical performance of the synthesized CdAl4O7/CdO nanocomposites using a three-electrode chronopotentiometry system. According to the results, the synthesized nanocomposites are capable of storing 1750 mAh/g of hydrogen at a constant current of 1 Amp. By using green tea extract as a natural structure-directing agent, the CdAl4O7/CdO nanocomposite can be developed more sustainably as high-performance hydrogen storage materials. Ultimately, this work contributes to the advancement of sustainable energy storage through the synthesis of a promising new material.


Assuntos
Hidrogênio , Nanocompostos , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Difração de Raios X , Chá/química
4.
Ecotoxicol Environ Saf ; 269: 115801, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064791

RESUMO

In the present day, the widespread presence of lingering contaminants in ecosystems has prompted scientists to develop novel semiconductor nanoarchitectures that assist in photocatalytic reactions mediated by visible light. As a result, we propose to prepare a series of Dy-Mn-O based nano-catalysts using a sonochemical approach utilizing various ionic phases of surfactants as structure-directing agents. In this study, X-ray diffraction (XRD) and Rietveld refinement techniques were used to explore the fundamental effects of surfactants on the compositional-structural features of the materials. In terms of morphological profiles, DyMnO3/Dy2O3 (DM) nanostructures fabricated with Triton X-80 as a structure-directing agent showed the best uniformity with an acceptable size range between 14.14 and 52.35 nm. In the visible-light-driven photocatalytic domain, these nanocomposites provide high responsiveness based on their optical band gap value of 2.0 eV. According to our findings, two individual factors affect dye activity, namely dye type and concentration, which is why a high decomposition efficiency of 78.8% was obtained for 10 ppm Acid violet (AV) using DyMnO3/Dy2O3 nanocomposites after 120 min of exposure to visible light. Furthermore, radical quenching test confirmation confirmed the mechanistic behind the degradation process. This indicates that active species of O2•- and •OH may play a significant role in photocatalysis. As a result of repeated processes over three consecutive cycles, binary DyMnO3/Dy2O3 nanocomposites had an efficiency of 64.4% in removing dyes from the environment, indicating their high stability.


Assuntos
Ecossistema , Nanocompostos , Luz , Nanocompostos/química , Tensoativos , Catálise
5.
J Mech Behav Biomed Mater ; 148: 106155, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852085

RESUMO

OBJECTIVES: This study aimed to synthesize and characterize an environmentally friendly nanohydroxyapatite (n-HA) and evaluate its impact on enamel mineral content when incorporated into a Pistachio oleo gum resin (Saqqez) bio-chewing gum for in-situ models. We compared the effects of this green nano-hydroxyapatite (G n-HA) with those of a commercially available synthetic nano-hydroxyapatite (S n-HA). METHODS: Various analytical techniques were employed including XRD, FESEM, FT-IR, EDX/SEM and TGA/DTA to characterize the crystallinity, size and composition of the G n-HA powder. Three chewing gum groups were formulated: (1) Saqqez gum containing 10% wt G n-HA, (2) Saqqez gum containing 10% wt S n-HA, and (3) pure Saqqez gum. In order to evaluate the impact of these chewing gums on enamel, intraoral appliances were fabricated, each containing six enamel specimens. Participants were instructed to chew the gums while wearing these appliances. The calcium (Ca+2) and phosphorus (P) levels in enamel specimens, both with and without exposure to an acid challenge, were quantified using EDX/SEM. FE-SEM was employed to capture the microstructure of the enamel surface. In terms of the statistical analysis, one-way ANOVA and Tukey's post hoc tests were utilized to compare the data, where the significance level (α) was set at 0.05. RESULTS: The characterization tests confirmed the successful synthesis of G n-HA. Furthermore, EDX/SEM analysis of the enamel specimens from the intraoral appliance revealed significant variations in calcium (Ca+2) content among the enamel specimens (P = 0.000). The S n-HA group, in particular, exhibited the highest Ca+2 content, while the pure Saqqez group displayed the lowest. Nonetheless, there was no statistically significant differences in phosphorus (P) content observed among the three groups (P = 0.27). CONCLUSIONS: Saqqez gum can be considered a wholesome natural chewing gum that serves, as a carrier for delivering remineralization agents to the tooth surfaces. This was evident in the groups containing n-HA, exhibiting elevated Ca+2 levels. It's noteworthy that G n-HA demonstrated less efficacy in enamel remineralization compared to S n-HA.


Assuntos
Pistacia , Humanos , Cálcio , Goma de Mascar , Durapatita , Fósforo , Método Simples-Cego , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Int J Biol Macromol ; 253(Pt 8): 127583, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37866577

RESUMO

Modification surface of chitosan nanoparticles using ZnO nanoparticles is important interest in drug delivery because of the beneficial properties. In this study, we proposed a chitosan/ZnO nanocomposite for the targeted delivery of antibacterial peptide (LL37). Synthesized LL37-loaded chitosan/ZnO nanocomposite (CS/ZnO/LL37-NCs) was based on the ionotropic gelation method. The antibacterial activity of the synthesized platform versus Methicillin-resistant Staphylococcus aureus (MRSA) was determined by the microdilution method in 10 mM sodium phosphate buffer. The biofilm formation inhibitory was also evaluated using microtiter plate method. In addition, the ability of CS/ZnO/LL37-NCs on the icaA gene expression level was assessed by the Real-Time PCR. The loading and release investigations confirmed the suitability of CS/ZnO-NCs for LL37 encapsulation. Results showed 6 log10 CFU/ml reduction in MRSA treated with the CS/ZnO/LL37-NPs. Moreover, CS/ZnO/LL37-NCs showed 81 % biofilm formation inhibition than LL37 alone. Also, icaA gene expression decreased 1-fold in the face of CS/ZnO/LL37-NCs. In conclusion, the modification surface of chitosan nanoparticles with ZnO nanoparticles is a suitable chemical platform for the delivery of LL37 that could be used as a promising nanocarrier for enhancing the delivery of antibacterial peptide and improving the antibacterial activity of LL37.


Assuntos
Quitosana , Staphylococcus aureus Resistente à Meticilina , Nanocompostos , Óxido de Zinco , Quitosana/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Biofilmes , Peptídeos/farmacologia , Testes de Sensibilidade Microbiana
7.
Ecotoxicol Environ Saf ; 266: 115578, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856984

RESUMO

In this study, a green approach was used to synthesize SmMnO3 magnetic nanoparticles via the auto combustion method, where pomegranate juice was utilized as a natural fuel. The concentration of fuel was varied to investigate its effect on the purity and morphology of SmMnO3 nanoparticles. The physiochemical properties of the synthesized nanoparticles, including crystal structures, morphology, optical, and magnetic properties, were investigated using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), Vibrating Sample Magnetometer (VSM), Diffuse Reflectance Spectroscopy (DRS), X-ray fluorescence (XRF) and Brunauer-Emmett-Teller (BET). The band gap of the as-synthesized nanoparticles was determined to be 1.8 eV, indicating their potential as a photocatalyst. The photocatalytic activity of SmMnO3 nanoparticles was evaluated against Methyl violet and Erythrosine, and the mechanism of photocatalyst was determined using EDTA, benzoic acid, and benzoquinone as scavengers. Photocatalytic activity was studied in both UV and visible light, and it was found that the maximum degradation (94%) was related to the degradation of Erythrosine (10 ppm) in the presence of visible light. The stability test of SmMnO3 performed and confirmed the stability of nanoparticles after 5 cycles. The results suggest that SmMnO3 nanoparticles synthesized via the green auto combustion method using pomegranate juice as a natural fuel can serve as a promising photocatalyst for the degradation of organic pollutants in the environment. Further studies can be conducted to investigate their potential in other applications.


Assuntos
Poluentes Ambientais , Nanopartículas , Poluentes da Água , Samário , Eritrosina , Luz , Água , Catálise
9.
Chemosphere ; 338: 139564, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467852

RESUMO

In recent years, water contamination has become a significant crisis, and it is crucial to find new materials that can efficiently eliminate these contaminants. The current work presents the Sm2CuO4 nanophotocatalyst for the decolorization of different water-soluble organic contaminants. The fabrication of Sm2CuO4 nanostructures was achieved using a simple and rapid sonochemical pathway, resulting in an optical bandgap of 1.62 eV as determined by diffuse reflectance spectroscopy. Several factors, including different organic contaminants, organic contaminant concentrations, Sm2CuO4 dosages, and the pH of the media, were scrutinized to achieve the best efficiency. The results manifested that Sm2CuO4 was highly effective in removing different organic contaminants from water. For example, when 30 mg of Sm2CuO4 was used with 20 mg L-1 methyl orange under visible irradiation for 100 min, 91.4% of the methyl orange was destroyed. Further investigation revealed that holes (h+) were primarily responsible for pollutant photodegradation when using Sm2CuO4 as a photocatalyst. This finding suggests that Sm2CuO4 could be an excellent candidate for developing new materials to effectively remove water contaminants.


Assuntos
Poluentes Ambientais , Nanoestruturas , Poluentes Químicos da Água , Poluentes da Água , Poluentes Químicos da Água/química , Nanoestruturas/química , Água , Catálise
10.
Ultrason Sonochem ; 95: 106362, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36907102

RESUMO

Thulium vanadate (TmVO4) nanorods were successfully prepared by a simple sonochemical approach using Schiff-base ligands. Additionally, TmVO4 nanorods were employed as a photocatalyst. The most optimal crystal structure and morphology of TmVO4 have been determined and optimized by varying Schiff-base ligands, the molar ratio of H2Salen, the sonication time and power, and the calcination time. A Eriochrome Black T (EBT) analysis revealed that the specific surface area was 24.91 m2/g. A bandgap of 2.3 eV was determined by diffuse reflectance spectroscopy (DRS) spectroscopy, which makes this compound suitable for visible photocatalytic applications. In order to assess the photocatalytic performance under visible light, two anionic dyes (EBT) and cationic dyes (Methyl Violet (MV)) were used as models. A variety of factors have been studied in order to improve the efficiency of the photocatalytic reaction, including dye type, pH, dye concentration, and catalyst loading. Under visible light, the highest efficiency was achieved (97.7%) when 45 mg TmVO4 nanocatalysts were present in 10 ppm Eriochorome Black T at pH = 10.

11.
Ultrason Sonochem ; 90: 106167, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36122482

RESUMO

Due to poor rate proficiency and electrochemical capacity of transition metal oxides, production electrode materials as operative way to develop the electrochemical performance is a crucial strategy to make sure the great electroactive sites and fast electron/ion diffusion route. In order to solve this problem, carbon-based nanocomposites as conductive substrates are applied. The nanostructured BaMoO4/ZnO was produced by sonochemical method in the presence of tween 20 as stabilizing agent. Effect of graphene quantum dots (GQDs) and graphene oxide (GO) for developing hydrogen capacity of BaMoO4/ZnO was studied by providing representative composites of BaMoO4/ZnO-GQDs and BaMoO4/ZnO-GO. For this purpose, GQDs was synthesized using green source of Spiraea crenata and the GO provided by commercial company. The structural analysis shows preparation of scales-like morphology of BaMoO4/ZnO without any impurities through SEM, TEM, XRD, EDS and FT-IR characterization data. Also, the specific surface area for BaMoO4/ZnO-GQDs (11 m2/g) and BaMoO4/ZnO-GO (124 m2/g) nanocomposites increased by comparing to BaMoO4/ZnO (9.1 m2/g). The resultant nanocomposites used as new active compounds for applying in hydrogen storage strategies using cyclic voltammetry and chronopotentiometry tests. Comprehensively, the hydrogen capacitance after 15 cycles was demonstrated on the nanostructured BaMoO4/ZnO about 129 mAhg-1. It demanded the maximum capacitance for BaMoO4/ZnO-GQDs and BaMoO4/ZnO-GO nanocomposites were 284 and 213 mAhg-1 respectively, which was higher than the initial nanostructured BaMoO4/ZnO. It was exposed from the carbon based structured that; the endorsed electrochemical hydrogen storage (EHS) performance is ascribed to the reaction of the redox pair of Mo6+ /Mo5+ at the active sites throughout the EHS procedure. This study delivers a novel plan and potential sorption electrode materials to progress the intrinsic action of conductive compounds.


Assuntos
Grafite , Óxido de Zinco , Grafite/química , Óxido de Zinco/química , Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Eletrodos , Óxidos/química
12.
RSC Adv ; 12(36): 23481-23502, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090397

RESUMO

The elimination of toxic and hazardous contaminants from different environmental media has become a global challenge, causing researchers to focus on the treatment of pollutants. Accordingly, the elimination of inorganic and organic pollutants using sustainable, effective, and low-cost heterogeneous catalysts is considered as one of the most essential routes for this aim. Thus, many efforts have been devoted to the synthesis of novel compounds and improving their catalytic performance. Recently, palladium- and copper-based hydrogels have been used as catalysts for reduction, degradation, and decomposition reactions because they have significant features such as high mechanical strength, thermal stability, and high surface area. Herein, we summarize the progress achieved in this field, including the various methods for the synthesis of copper- and palladium-based hydrogel catalysts and their applications for environmental remediation. Moreover, palladium- and copper-based hydrogel catalysts, which have certain advantages, including high catalytic ability, reusability, easy work-up, and simple synthesis, are proposed as a new group of effective catalysts.

15.
Biomed Pharmacother ; 153: 113369, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35780615

RESUMO

Medicine/nanotechnology as a new and applicable technique according to drug delivery systems has gained great consideration for cancer treatment. Polysaccharides including, cellulose, ß-cyclodextrin and sodium carboxymethyl cellulose and chitosan as natural bio-materials, are appropriate candidates for designing and formulations of these nanosystems because of the exceptional advantages such as bio-compatibility, bio-degradability, non-toxicity, and gelling characteristics. An intelligent drug delivery platform based on these hybrids nowadays is developed, which can be used for dual-responsive dual-drug delivery. Nanotechnology accompany with biological molecules has been carefully considered to decrease the drawbacks of conventional cancer treatments. Consequently, this review is intended to state and investigate on the latest development on the combination treatment of platforms based on the hybrids of anticancer drugs/nanoparticles/Polysaccharides in the fields of biomedical therapeutics and cancer therapy owing to the bio-compatibility, great surface area, good chemical and mechanical features, the challenges and future perspectives are reported as well.


Assuntos
Quitosana , Leucemia , Nanopartículas , beta-Ciclodextrinas , Carboximetilcelulose Sódica/química , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Nanopartículas/química , Sódio
16.
Carbohydr Polym ; 291: 119634, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698353

RESUMO

In this study, the fabrication of LL37-loaded chitosan nanoparticles (CS/LL37-NPs) was based on an ionotropic gelation method between sodium tripolyphosphate (TPP) and chitosan. Synthesized chitosan nanoparticles (CS-NPs) were approved by Fourier Transform Infrared (FTIR), UV-vis spectroscopy, Dynamic Light Scattering (DLS), Scanning Electron Microscope (SEM), and Transmission Electron Microscopy (TEM). The encapsulation efficiency of LL37 in this delivery system (CS/LL37-NPs) was 86.9%. According to in vitro release profile, the release of LL37 from CS/LL37-NPs was almost complete after 5 days. Additionally, CS/LL37-NPs can cause an increase in the half-life and prolonged LL37 antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA). This delivery system demonstrated 68% biofilm formation inhibition compared to the LL37 alone. Also, icaA gene expression in the face of CS/LL37-NPs was significantly decreased. This study showed the important role of delivery systems in enhancing LL37 antibacterial and antibiofilm activity which can be suggested as a promising agent in the inhibition of bacterial growth and the prevention of biofilm formation.


Assuntos
Quitosana , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Antibacterianos/farmacologia , Biofilmes , Quitosana/química , Quitosana/farmacologia , Nanopartículas/química , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Sci Total Environ ; 836: 155527, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35508244

RESUMO

In this project, the protective effect of Biebersteinia multifida root extract (BMRE) against corrosion of 1018 low carbon steel (1018LCS) in HCl solutions was appraised by assessing weight loss, electrochemical impedance spectroscopy (EIS), and polarization at 25 °C. The maximum inhibitory efficacy for the concentration of 1 g/l of the BMRE was 92.8% at 25 °C after 2 h and increased to 95.3% after 24 h of immersion. Polarization experiments have shown that the extract in acidic solutions can act as a mixed corrosion inhibitor. The corrosion inhibitory efficacy of BMRE decreased with increasing temperature, and at all temperature settings studied, the adsorption of BMRE molecules on 1018 LCS was consistent with the Langmuir adsorption isotherm. The Scanning Electron Microscopy (SEM) analysis confirmed the protection of 1018 LCS in the acidic solution containing BMRE extract. Quantum chemistry studies of four main constituents of the extract called vasicinone, umbelliferon, scopoletin, and ferulic acid were performed by density functional theory, DFT, in neutral and protonated states. Calculated quantum parameters were used to investigate the active sites and donor-receptor interactions of molecules.


Assuntos
Magnoliopsida , Aço , Ácidos , Carbono/química , Corrosão , Extratos Vegetais/química
18.
Sci Rep ; 12(1): 8103, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577885

RESUMO

Halloysite nanotubes (HNTs) with high active sites are used as natural layered mineral supports. Sulfur- and nitrogen-co doped graphene quantum dots (S, N-GQDs) as conductive additive and CoFe2O4 as the electrocatalyst was decorated on a HNT support to design an effective and environmentally friendly active material. Herein, an eco-friendly CoFe2O4/S, N-GQDs/HNTs nanocomposite is fabricated via a green hydrothermal method to equip developed hydrogen storage sites and to allow for quick charge transportation for hydrogen storage utilization. The hydrogen storage capacity of pure HNTs was 300 mAhg-1 at a current density of 1 mA after 20 cycles, while that of S, N-GQD-coated HNTs (S, N-GQDs/HNTs) was 466 mAhg-1 under identical conditions. It was also conceivable to increase the hydrogen sorption ability through the spillover procedure by interlinking CoFe2O4 in the halloysite nanoclay. The hydrogen storage capacity of the CoFe2O4/HNTs was 450 mAhg-1, while that of the representative designed nanocomposites of CoFe2O4/S, N-GQDs/HNTs was 600 mAhg-1. The halloysite nano clay and treated halloysite show potential as electrode materials for electrochemical energy storage in alkaline media; in particular, ternary CoFe2O4/S, N-GQD/HNT nanocomposites prove developed hydrogen sorption performance in terms of presence of conductive additive, physisorption, and spillover mechanisms.

19.
Talanta ; 247: 123593, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35636361

RESUMO

Today, in most fields, wide research has been done in the manufacture of biosensors and the detection of various types of substances, including drugs. Nevertheless, the analytical detection of drugs from a biological sample by a simple and portable method for on-site detection is still important and very challenging. This paper investigates the electrochemical determination of the mefenamic acid (MEF), with a novel carbon paste electrode modified with terbium titanate nanostructures (TTN/CPE). The effect of the capping agent on the morphology and size of terbium titanate synthesized from terbium nitrate in the presence of ethylene glycol (EG) as a stabilization agent is investigated. The as-produced nanostructures are characterized by X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). Electrochemical studies in optimized conditions indicate MEF has two linear responses in the range of 1.0 × 10-2-4.0 × 102 µM with a detection limit of 2.4 nM at the surface of TTN/CPE. The suggested sensor reveals good sensitivity, selectivity, stability, and reproducibility and can be utilized for some important biological samples and wastewater with satisfactory results.


Assuntos
Carbono , Nanopartículas , Carbono/química , Indústria Farmacêutica , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Ácido Mefenâmico , Nanopartículas/química , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Térbio , Titânio/química , Águas Residuárias
20.
Inorg Chem ; 61(18): 6750-6763, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35465668

RESUMO

Owing to the extensive requirement for renewable energy sources such as hydrogen, great efforts are being devoted to optimizing the active ingredients for advanced hydrogen storage. In this regard, an ideal spinel-perovskite nanocomposite based on Li-Mn-Fe-Si materials was successfully fabricated via a one-pot hydrothermal route to store hydrogen electrochemically. To optimize both the phase composition and morphological features of nanostructures, the reaction was engineered under different conditions. Li-Mn-Fe-Si spinel-perovskite diphase structures were created with diverse shapes of polyhedral-shaped bulk particles, nanoparticles, nanoplates, and hierarchical structures. The alteration of multiple factors such as hydrothermal reaction time, temperature, polymeric surfactant type, and calcination temperature was surveyed to achieve the optimized size and morphology of the nanoproducts to be obtained. The morphological changes, structural regulations, porosity, and magnetic properties of the nanosized products were studied via field-emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray powder diffraction (XRD), Raman spectroscopy, Brunauer-Emmett-Teller (BET), and vibrating sample magnetometer (VSM) analyses. In addition, the electrochemistry features of the Li0.66Mn1.85Fe0.43O4/Fe2.57Si0.43O4/FeSiO3 (LMFO/FSO) nanocomposites were introduced on the basis of discharge capacity, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry(CV) methods in an alkaline electrolyte. The discharge capacity of the LMFO/FSO nanostructures with a nanoplate-like morphology as an optimal sample was calculated to be 910 mAh/g after 15 cycles at a constant current of 1 mA. The electrochemistry results confirm that the hydrogen storage capability of nanoplate composites is higher than those of other morphologies due to their superior surface area and faster electron transfer. Besides, this proposed strategy could simultaneously manipulate the architectural and compositional complexities to generate a superior electrochemical behavior in energy storage devices.

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