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1.
Ecotoxicol Environ Saf ; 269: 115801, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38064791

ABSTRACT

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.


Subject(s)
Ecosystem , Nanocomposites , Light , Nanocomposites/chemistry , Surface-Active Agents , Catalysis
2.
Ultrason Sonochem ; 95: 106362, 2023 May.
Article in English | MEDLINE | ID: mdl-36907102

ABSTRACT

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.

3.
Inorg Chem ; 61(18): 6750-6763, 2022 May 09.
Article in English | MEDLINE | ID: mdl-35465668

ABSTRACT

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.

4.
J Colloid Interface Sci ; 613: 1-14, 2022 May.
Article in English | MEDLINE | ID: mdl-35030412

ABSTRACT

In this study, we firstly introduce an ultra-high sensitive V3.6Mo2.4O16-chitosan (MV-CHT) nanocomposite for electrochemical hydroxychloroquine sulfate (HCQ) monitoring toward paracetamol (PCM) and pantoprazole (PPZ) in environmental and clinical diagnostics. The single-phase MV nanostructures are prepared via the sol-gel pechini route, followed by engineering maleic acid as a structure-directing agent. The stabilization of the MV electro-catalysts is adopted by varying critical factors such as calcination temperature, different chelating ligands, chelating molality and cross-linker concentration. The structural and morphological characterizations, namely, ordered active sites, structural integrity, porous network and dispersibility on the cationic polymer are confirmed by physicochemical analyses. Also, analytical nature of the MV-CHT modified carbon paste electrode (MV-CHT/CPE) is constructed via electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) techniques. As a result, the nano-MV-CHT/CPE platforms with 10% of polymeric matrixes delivered the boosted analytical performance in terms of linear ranges (0.0019-194.0 µM), lower detection limit (LOD = 0.224 nM), together with excellent sensitivity and selectivity. The novel combination of MV nanoparticles and CHT provide the fluent channels for rapid charge transport and effective surface area. Such results illustrate the synergistic and interaction capability of MV-CHT-based sensing catalysts with bioactive molecules, which make them as superior drug monitoring devices.


Subject(s)
Chitosan , Nanocomposites , Carbon , Electrochemical Techniques , Electrodes , Hydroxychloroquine , Limit of Detection , Molybdenum , Vanadates
5.
Biosens Bioelectron ; 178: 113017, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33493895

ABSTRACT

A novel nano-electrocatalyst based on Cu5V2O10 is successfully fabricated by one-pot hydrothermal treatment and used for the examination of mefenamic acid (MFA) in real samples, for the first time. Controlling the combined factors of complexing agent's (4, 4'-Diaminodiphenylmethane, DDM) molar ratio, hydrothermal temperature, and reaction time is responsible for providing the optimal structural and morphological changes of the crystals. The effect of operating conditions of Cu5V2O10 nanostructures is investigated using FT-IR, XRD, and EDX as structural and elemental analyses. Also, other properties such as particle size and morphological studies were accomplished by FE-SEM, and HR-TEM. The results reveal that the monoclinic phase of Cu5V2O10 with particle size of 34 nm is the outcome of hydrothermal treatment of 200 °C for 18 h, which DDM template with molar ratio of 2.0 M serves as phase stabilizing matrix. Herein, it is demonstrated the electrochemical biosensing characteristics of the nano-scale Cu5V2O10 modified carbon paste electrode (CV/CPE) by voltammetry techniques. The drug sensing capabilities of the boosted CV/CPE platform exhibit linear dynamic range of 0.01-470 µM, and low detection limit of 2.34 nM with excellent sensitivity and selectivity. The appropriate electrical conductivity and layered structure of the compound causes a valuable platform for minimally invasive assessment of MFA in biological and pharmaceutical media with recovery rate of 98.3%-110.0% and 93.6%-106.7%, respectively. As a result, the proposed nanostructures as great candidate offer excellent electrocatalytic activity in biomedicine applications.


Subject(s)
Biosensing Techniques , Nanostructures , Pharmaceutical Preparations , Carbon , Electrochemical Techniques , Electrodes , Limit of Detection , Mefenamic Acid , Spectroscopy, Fourier Transform Infrared
6.
Ultrason Sonochem ; 61: 104822, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31670255

ABSTRACT

In the current research, various conventional chemical preparation methods without ultrasound aid (precipitation, microwave, and hydrothermal) were compared with sonochemical procedure and were performed for providing of PrVO4 nanostructures using Schiff-base ligands. The small size products with monodisperse particles (~39 nm) optimized by sonochemical fabrication method and using H2 acacpn ligand via ultrasonic probe with power of 60 W and frequency of 18 KHz. The produced PrVO4 nanostructures applied for degradation of diverse organic dyes through the photocatalytic process. Dye types, pH adjusting of dye, dosage of catalyst, synthesis method of nanoparticles and light source as impressive factors inquired for dye removal ability. The outcomes presented the removal efficiency of Eriochorom Black T in optimal conditions of pH = 11 and the catalysts amounts of PrVO4 were adjusted to be 0.05 g. The PrVO4 photocatalyst shows high removal efficiency (ca 86.92 and 89.61%) after 90 min of operation under UV light. The best-obtained framework confirmed the basic study to compare different method in order to acquire suitable catalyst materials. The simple, fast and economic strategy for synthesis PrVO4 with high photodegradation efficiency is sonochemical method against other ways, and it could be extended to the most efficient catalyst materials for water treatment. Consequently, the PrVO4 may suggestion a hopeful avenue for designing the novel generation, low-cost and outstanding potential photocatalyst materials for water treatment.

7.
Ultrason Sonochem ; 58: 104686, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31450328

ABSTRACT

Solar photocatalytic process has been shown to be an energy effective and eco-friendly degradation of unwanted pollutants present in the industrial wastewater. The present study introduces the preparation and characterization of novel holmium vanadate (HoVO4) nanostructures that fully used in the photodegradation efficiency of anionic and cationic organic pollutants. HoVO4 synthesized via a sonochemical-assisted route and triethylenetetramine (TETA) was used as a capping and precipitation agent. The experiments were carried out under a probe as sonication source, and its power was adjusted in 30 W (9 kHz), 50 W (15 kHz) and 80 W (24 kHz) for different samples. The obtained nanostructures were characterized by surface analytical and spectral techniques includes XRD, FT-IR, SEM, TEM and UV-visible spectra measurements. The HR-SEM images reveal that HoVO4 exists as a spindle-shape with spherical morphology together. HR-TEM images reveal that prepared catalyst has a spherical structure with uniform particle size. The results outline 67.6% elimination of methyl violet dye within 90 min under UV light in the presence of the optimal nano-sized formulation of 24.5 nm size. The prepared photocatalyst possesses high stability and reusability without appreciable loss of catalytic activity up to three runs.

8.
Ultrason Sonochem ; 59: 104719, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31421621

ABSTRACT

In order to obtain a highly efficient photocatalyst for water treatment, the sonochemical procedure applied to fabrication of excellent DyVO4 nanoparticles. A comparative study between two different synthesis routes (precipitation and sonochemical) was investigated in this work. Also, the influence of anionic, cationic and nonionic surfactant was studied on the formation of uniform particles. Further, the photocatalytic performance over the DyVO4 nanoparticles was studied under visible light by modifying the operational variables. Investigation of the photocatalytic mechanism process was conducted using hole scavengers for capturing reactive species. It was found that the DyVO4 nanoparticles sonochemically (a ultrasound probe with power of 60 W (18 KHz)) synthesized in presence of CTAB as an optimum condition, are uniform with average size of ~24 nm. The results showed that DyVO4 could remove near 88% of erythrosine, under the optimum condition of 0.05 g catalyst dosage and at initial pH 4. The DyVO4 maintained relatively high stability and reusability removal for erythrosine after five repeated cycles. The results could provide effective functional materials for elimination of chemical contaminants from wastewater through the photocatalytic process.

9.
J Environ Manage ; 230: 266-281, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30292015

ABSTRACT

Neodymium Vanadate (NdVO4) nanostructures were successfully synthesized via a modified solid state method in the presence of ligand. These nanoparticles were further used as a photocatalyst. Primarily the best structural formations and smallest crystallite sizes of the systems were identified and optimized by changing the calcination time, calcination temperature and molar ratio of the ligand. The cationic (Methyl Violet (MV)), and anionic (Eosin Y (EY) and Eriochrome Black T (EBT)) dyes were used as a model to evaluate the photoactivity under UV-Vis irradiation. Several operational factors were examined to improve the photocatalytic efficiency include type of dye, type of light source, pH and dye concentration. As a result, the best efficiency in 5 ppm Eriochorome Black T at pH = 11 was achieved in the presence of 0.05 g NdVO4 nanocatalysts.


Subject(s)
Nanoparticles/chemistry , Neodymium/chemistry , Vanadates/chemistry , Water Purification/methods , Catalysis , Coloring Agents/chemistry , Nanostructures/chemistry , Photochemical Processes
10.
Ultrason Sonochem ; 42: 201-211, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29429662

ABSTRACT

This paper presents a new approach to preparation of neodymium vanadate nanostructures via facile sonochemical route. Several parameters were compared to reach optimum size and uniformity of as-made samples. These factors include sonication time, sonication power, solvent and using ethylenediamine as alkaline and capping agent, for the first time. Neodymium vanadate nano-photocatalyst applied in decolouration of dye as organic contaminant. Effect of type of dye, type of irradiation source, pH and catalyst loading was described on improving efficiency of catalyst function. Numerous techniques were specified in order to determine purity, morphology and optical properties of products consist XRD, FT-IR, EDX, SEM, TEM and DRS.

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