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1.
Chemosphere ; 364: 143017, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39103104

RESUMO

Due to the increased human activities in burning of fossil fuels and deforestation, the CO2 level in the atmosphere gets increased up to 415 ppm; although it is an essential component for plant growth, an increased level of CO2 in the atmosphere leads to global warming and catastrophic climate change. Various conventional methods are used to capture and utilize CO2, among that a feasible and eco-friendly technique for creating value-added products is the CO2RR. Photochemical, electrochemical, thermochemical, and biochemical approaches can be used to decrease the level of CO2 in the atmosphere. The introduction of nano-catalysts in the reduction process helps in the efficient conversion of CO2 with improved selectivity, increased efficiency, and also enhanced stability of the catalyst materials. Thus, in this mini-review of nano-catalysts, some of the products formed during the reduction process, like CH3OH, C2H5OH, CO, HCOOH, and CH4, are explained. Among different types of metal catalysts, carbonaceous, single-atom catalysts, and MOF based catalysts play a significant role in the CO2 RR process. The effects of the catalyst material on the surface area, composition, and structural alterations are covered in depth. To aid in the design and development of high-performance nano-catalysts for value-added products, the current state, difficulties, and future prospects are provided.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/química , Catálise , Carbono/química , Metais/química , Oxirredução , Nanoestruturas/química , Atmosfera/química
2.
Chemosphere ; 357: 141934, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615957

RESUMO

In this study, the BiOBr/rGO nanocomposite photocatalysts are fabricated by a facile solvothermal method. The BiOBr growth on reduced graphene oxide (rGO) sheet could improve BiOBr's photocatalytic activity by increasing its adsorption ability, surface area, and charge carriers' separation efficiency. The prepared nanocomposites were characterized by XRD, Raman, FESEM, EDS, XPS, and UV-visible DRS. The BiOBr/rGO (BRG) nanocomposites showed improved photocatalytic activity for the photodegradation of Rhodamine B (RhB) dye and Tetracycline (TC) under visible light irradiation. Rhodamine B and tetracycline degradation efficiency were about 96% and 73% within 120 min under visible light irradiation. The PL analysis indicates that BiOBr/rGO nanocomposite exhibited maximum separation efficiency of photoinduced charge carriers. The trapping test confirmed that O2- and h+ are significant active photodegradation species. The GC-MS spectra detected the two plausible transformation routes of tetracycline degradation. The current work presented a low-cost and facile approach for fabricating Bi-based composites.


Assuntos
Antibacterianos , Bismuto , Grafite , Luz , Nanocompostos , Fotólise , Rodaminas , Tetraciclina , Grafite/química , Tetraciclina/química , Rodaminas/química , Bismuto/química , Catálise , Antibacterianos/química , Cinética , Nanocompostos/química , Poluentes Químicos da Água/química
3.
J Mol Model ; 29(12): 388, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38017290

RESUMO

CONTEXT: In this work, the 4-dimethylaminopyridinium-2,4-dinitrophenolate (4DMAP + 2,4DNP) by slow evaporation solution growth method has been presented. The Fourier transform infrared (FT-IR) (4000-400 cm-1) and FT-Raman (4000-50 cm-1) spectra were recorded for the grown crystal. METHODS: The computational calculation has been carried out with density functional theory (DFT) in ground state with Gaussian program package. Optimized geometrical parameters (bond distances, bond angles, and dihedral angles) have been obtained and compared with X-ray crystallography data. The calculated fundamental vibrational frequencies from DFT/B3LYP with 6-311 + + G(d,p) level of theory were scaled so as to agree with the observed results, and the scaling factors were reported. RESULTS: Experimental and computed ultraviolet-visible (UV-Vis) spectra in acetone and methanol solvents were found comparable to each other. Furthermore, the frontier molecular orbitals (FMOs) energies, molecular electrostatic potential (MEP), nonlinear optical (NLO), hirshfeld surface (HS), and global chemical descriptors of the molecule were also calculated. The thermal stability and the melting point of the title compound were analyzed by the thermogravimetric analysis/differential thermal analysis (TGA/DTA) techniques. The mechanical behavior of the organic single crystal was measured by Vickers micro-hardness method. The third-order nonlinear optical properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (ß), optical nonlinear susceptibility Reχ(3), and optical nonlinear susceptibility Imχ(3) were calculated by using the open and closed aperture Z-scan technique. CONCLUSION: The theoretical and experimental NLO values clearly proposed that the nonlinearity of 4DMAP + 2,4DNP molecule could be helped as a potential candidate for optical limiting, frequency doubling, and optical switching applications.

4.
Sci Rep ; 13(1): 16820, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798379

RESUMO

Defect engineering is a promising method for improving light harvesting in photocatalytic materials like Zinc sulphide (ZnS). By altering the S/Zn molar ratio during hydrothermal processes, Zn and S defects are successfully introduced into the ZnS crystal. The band structures can be modified by adding defects to the crystal structure of ZnS samples. During the treatment process, defects are formed on the surface. XRD and Raman studies are used for the confirmation of the crystallinity and phase formation of the samples. Using an X-ray peak pattern assessment based on the Debye Scherer model, the Williamson-Hall model, and the size strain plot, it was possible to study the influence of crystal defect on the structural characteristics of ZnS nanoparticles. The band gap (Eg) values were estimated using UV-Vis diffuse spectroscopy (UV-Vis DRS) and found that the Eg is reduced from 3.28 to 3.49 eV by altering the S/Zn molar ratio. Photoluminescence study (PL) shows these ZnS nanoparticles emit violet and blue radiations. In keeping with the results of XRD, TEM demonstrated the nanoscale of the prepared samples and exhibited a small agglomeration of homogenous nanoparticles. Scanning electron microscopy (SEM) was used to examine the surface morphology of the ZnS particles. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS) were used to evaluate and validate the elemental composition. XPS results indicate the presence of defects on the prepared ZnS nanoparticles. For the investigation of vacancy-dependent catalytic activity under exposure to visible light, defective ZnS with different quantities of Zn and S voids are used as catalysts. The lowest S/Zn sample, ZnS0.67 and the highest S/Zn sample, ZnS3, show superior photocatalytic activity.

5.
Chemosphere ; 341: 139979, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37659517

RESUMO

Over the past 50 years, the emergence of plastic waste as one of the most urgent environmental problems in the world has given rise to several proposals to address the rising levels of contaminants associated with plastic debris. Worldwide plastic production has increased significantly over the last 70 years, reaching a record high of 359 million tonnes in 2020. China is currently the world's largest plastic producer, with a share of 17.5%. Of the total marine waste, microplastics account for 75%, while land-based pollution accounts for responsible for 80-90%, and ocean-based pollution 10-20% only in overall pollution problems. Even at small dosages (10 µg/mL), microplastics have been found to cause toxic effects on human and animal health. This review examines the sources of microplastic contamination, the prevalent reaches of microplastics, their impacts, and the remediation methods for microplastic contamination. This review explains the relationship between the community composition and the presence of microplastic particulate matter in aquatic ecosystems. The interaction between microplastics and emerging pollutants, including heavy metals, has been linked to enhanced toxicity. The review article provided a comprehensive overview of microplastic, including its fate, environmental toxicity, and possible remediation strategies. The results of our study are of great value as they illustrate a current perspective and provide an in-depth analysis of the current status of microplastics in development, their test requirements, and remediation technologies suitable for various environments.


Assuntos
Recuperação e Remediação Ambiental , Microplásticos , Animais , Humanos , Plásticos , Ecossistema , Poluição Ambiental
6.
Luminescence ; 38(11): 1892-1903, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37560763

RESUMO

Praseodymium (Pr)-doped ZnS nanoparticles were synthesized using a low-cost microwave-assisted technique and investigations on their structure, morphology, optical properties, Raman resonance, dielectric properties, and luminescence were conducted. Broad X-ray diffraction peaks suggested the formation of low-dimensional Pr-doped ZnS nanoparticles with a cubic structure that was validated using transmission electron microscopy (TEM)/high-resolution TEM analysis. The energy gaps were identified using diffuse reflectance spectroscopy and it was found that the values varied between 3.54eV and 3.61eV for different samples. Vibrational experiments on Pr-doped ZnS nanoparticles revealed significant Raman modes at ~270 and ~350 cm-1 that were associated with optical phonon modes that are shifted to lower wavenumbers, indicating phonon confinement in the synthesized products. The photoluminescence (PL) spectra of all samples demonstrated that the pure and Pr-doped ZnS nanoparticles were three-level laser active materials. Energy-dispersive X-ray spectroscopy and mapping study confirmed the homogeneous presence of Pr in ZnS. TEM studies showed that the particles were of very small size and in the cubic phase. The samples had high dielectric constant values between 13 and 24 and low loss values, according to the dielectric analysis. With an increase in frequency and a change in the Pr content of ZnS, an intense peak could be seen in the PL spectra at a wavelength of 360 nm, and some other peaks observed corresponded to the transition of Pr3+ . The produced nanoparticles were appropriate for optoelectronic applications due to their short dimension, high energy gap, high dielectric constant, and low loss values.


Assuntos
Nanopartículas , Praseodímio , Micro-Ondas , Nanopartículas/química , Compostos de Zinco/química
7.
Chemosphere ; 338: 139432, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37419154

RESUMO

In this research, novel Bi2WO6/MWCNT nanohybrids were synthesized via a cost-effective hydrothermal route. The photocatalytic performance of these specimens was tested through the photodegradation of Ciprofloxacin (CIP) under simulated sunlight. Various physicochemical techniques systematically characterized the prepared pure, Bi2WO6/MWCNT nanohybrid photocatalysts. The XRD and Raman spectra revealed the structural/phase properties of Bi2WO6/MWCNT nanohybrids. FESEM and TEM pictures revealed the attachment and distribution of plate-like Bi2WO6 nanoparticles along the nanotubes. The optical absorption and bandgap energy of Bi2WO6 was affected by the addition of MWCNT, which was analyzed by UV-DRS spectroscopy. The introduction of MWCNT reduces the bandgap value of Bi2WO6 from 2.76 to 2.46 eV. The BWM-10 nanohybrid showed superior photocatalytic activity for CIP photodegradation; 91.3% of CIP was degraded under sunlight irradiation. The PL and transient photocurrent test confirm that photoinduced charge separation efficiency is better in BWM-10 nanohybrids. The scavenger test indicates that h+ & •O2 have mainly contributed to the CIP degradation process. Furthermore, the BWM-10 catalyst demonstrated outstanding reusability and firmness in four successive cycles. It is anticipated that the Bi2WO6/MWCNT nanohybrids will be employed as photocatalysts for environmental remediation and energy conversion. This research presents a novel technique for developing an effective photocatalyst for pollutant degradation.


Assuntos
Antibacterianos , Ciprofloxacina , Processos Fotoquímicos , Luz Solar , Ciprofloxacina/química , Fotólise , Nanoestruturas/química , Análise Espectral Raman , Poluentes Ambientais/química , Antibacterianos/química
8.
Micromachines (Basel) ; 14(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36985012

RESUMO

A graphene oxide (GO)/poly 3-methyl aniline (P3MA) photodetector has been developed for light detection in a broad optical region: UV, Vis, and IR. The 3-methyl aniline was initially synthesized via radical polymerization using an acid medium, i.e., K2S2O8 oxidant. Consequently, the GO/P3MA composite was obtained through the adsorption of GO into the surface of P3MA. The chemical structure and optical properties of the prepared materials have been illustrated via XRD, FTIR, SEM, and TEM analysis. The absorbance measurements demonstrate good optical properties in the UV, Vis, and near-IR regions, although a decrease in the bandgap from 2.4 to 1.6 eV after the composite formation was located. The current density (Jph) varies between 0.29 and 0.68 mA·cm-2 (at 2.0 V) under dark and light, respectively. The photodetector has been tested using on/off chopped light at a low potential, in which the produced Jph values decrease from 0.14 to 0.04 µA·cm-2, respectively. The GO/P3MA photodetector exhibits excellent R (and D) values of 4 and 2.7 mA·W-1 (0.90 × 109 and 0.60 × 109 Jones) in the UV (340 nm) and IR (730 nm) regions, respectively. The R and D values obtained here make the prepared photodetector a promising candidate for future light detection instruments.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36943565

RESUMO

Among different types of semiconductor photocatalysts, MoS2 hybridized with graphitic carbon heterojunction has developed the most promising "celebrity" due to its static chemical properties, suitable band structure, and facile synthesis. Physiochemical and surface characterizations were revealed with structural, electronic, and optical analysis. Diffused reflectance spectroscopy evidenced the energy band gap tailoring from 2.62 eV for pure g-C3N4 and 1.68 eV for MoS2 to 2.12 eV for the hybridized heterojunction nanocomposite. Effective electron/hole pair separation, rise in redox species, and great utilization of solar range because of band gap modifying leading to greater degradation efficacy of g-C3N4/MoS2 heterojunction. The photocatalytic degradation with MoS2/g-C3N4 heterojunction catalyst to remove methylene blue dye was remarkably enriched and much higher than g-C3N4. By carefully examining the stimulus aspects, a probable mechanism is suggested, assuming that the concurring influence of MoS2 and g-C3N4, the lesser crystallite size, and more solubility in aquatic solution furnish the efficient e--h+ pair separation and tremendous photocatalytic degradation activity. This work delivers a novel idea to improve the efficient MoS2/g-C3N4 heterojunction for improved photocatalytic degradation in environmental refinement.

10.
J Mol Model ; 29(2): 45, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36656395

RESUMO

CONTEXT: The improvement of new organic flavone-based donor-spacer-acceptor (D-π-A) type dye molecules of the 3-(4-hydroxypiperidin-2-yloxy)-7-hydroxy-2-(3,4-dihydroxyphenyl)-4H-chromen-4-one (D1), 7-hydroxy-2-(3,4-dihydroxyphenyl)-3-(piperidin-4-yloxy)-4H-chromen-4-one (D2), and 3-((2-aminopyridin-4-yloxy)methoxy)-7-hydroxy-2-(3,4-dihydroxyphenyl)-4H-chromen-4-one (D3) were successfully designed and synthesized for dye-sensitized solar cells (DSSCs). METHODS: Here, we discuss the synthesis of flavone compounds as well as their photophysical and electrochemical characterization. Using the Gaussian 09w software, the electronic structures and apsorption spectra have been calculated at the B3LYP, B3PW91, CAM-B3LYP, MPW1PW91, PBEPBE, and ωB97XD theory with the 6-311G(d,p) basis sets. RESULTS: The computed values of the D2 molecule ground state optimized HOMOs-LUMOs energy is well positioned for advantageous charge transfer (CT) into the semiconducting material (TiO2) as well as the electron injection process. With a high power conversion efficiency (PCE) of 3.46% (VOC = 0.718 V, JSC = 7.07 mA cm-2, and FF = 0.68), the D2 compound also demonstrated good photovoltaic (PV) properties. CONCLUSION: These findings unequivocally demonstrate that altering the D-π-A metal-free organic material electron-withdrawing capacity is a useful strategy for enhancing the optical and electrical characteristics of the organic PV system.


Assuntos
Flavonas , Corantes , Eletricidade , Eletrônica , Elétrons
11.
J Environ Manage ; 330: 117134, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584459

RESUMO

Recently, the major environmental pollution produced by the release of wastewater in liquid type is one of the most extensive forms of foremost pollution in water ecosystems. In this article, the Bi2O3/g-C3N4 nanocomposite with a direct Z-scheme was effectively obtained by a facile hydrothermal system. The crystal structures, surface morphology, chemical composition, and the optical belongings of the as-obtained composite catalysts were examined by Power XRD, FT-IR spectra, High-resolution XPS spectra, FE-SEM images with EDX spectra, High-resolution TEM images, UV-Vis DRS, and PL spectra respectively. Furthermore, the photocatalytic performance was assessed by the degradation of aqueous Rhodamine B (Rh B) dye under visible-light exposure. The Bi2O3/g-C3N4 composite photocatalysts (PCs) showed the maximum photo-degradation efficiency through a rate constant value of 0.0149 min-1, which is 4.9 and 5.3 folds superior to Bi2O3, and GCN, respectively. The better GBO2 nanocomposite PCs showed a superior photocatalytic degradation performance (>82%) of aqueous Rh B dye after five successive recycles. Moreover, based on these outcomes of the radical scavenging test, a direct and effective Z-scheme photocatalytic charger transfer mechanism was also projected. Finally, the reusability of the as-obtained Bi2O3/g-C3N4 nanocomposite has better stability and reusability, which was a favourable applicant for wastewater handling.


Assuntos
Ecossistema , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Fontes de Energia Elétrica , Água
12.
J Mol Model ; 28(11): 349, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36214920

RESUMO

In this study, the computational studies of the PO3H2, CONHOH, and SO2H (A1-A3) molecules were investigated for optoelectronic applications on the basis of tetrahydroquinoline (C1-1) dye. Besides, a detailed calculation of the molecular structures, energy levels, driving force of injection, regeneration, non-linear optical (NLO) property, chemical hardness, excitation binding energy, light-harvesting efficiency (LHE), absorption spectra, and photovoltaic (PV) parameters were all discussed in details using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. The optoelectronic properties of C1-1-based A1-A3 molecules are originated to be tuned by changing the position of the acceptor. To get a maximum absorption spectrum of C1-1, Becke's three-parameter and Lee-Yang-Parr (B3LYP), Coulomb-attenuating method-B3LYP (CAM-B3LYP), and Head-Gordon model (ωB97XD) were used for the TD-DFT method. Results reveal that the TD-É·B97XD and 6-31G(d) combined functionals were provided reliable effects to the C1-1. Therefore, absorption spectra of the A1-A3 dyes were followed by the TD-É·B97XD/6-31G(d) techniques. The designed A1 (PO3H2) dye displayed a smaller energy gap and red-shifted broadened spectra than the other dyes and C1-1 can be utilized to get a better PV properties. In addition, NLO properties of the A1-A3 chromophores were calculated by the polarizability and first-order hyperpolarizability. Consequently, A1 dye has a superior value of the NLO activity. This study will deliver a valuable reference to the upcoming molecular proposal of tetrahydroquinoline dyes for optoelectronic applications.


Assuntos
Corantes , Corantes/química , Teoria da Densidade Funcional , Modelos Moleculares , Estrutura Molecular
13.
Nanomaterials (Basel) ; 12(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36014662

RESUMO

MoO3 thin films are fabricated using nebulizer spray pyrolysis technique, which is doped with Fe at various concentrations of 1, 2, 3, and 4% for ammonia gas sensors application at room temperature. X-ray diffraction (XRD) study confirms the growth of the crystal by Fe doping up to 3%, nano rods shape morphology of the thin film samples observed by field emission scanning electron microscope (FESEM), reduction in bandgap is evidenced via UV-VIS spectrophotometer. Gas sensing study is performed using gas analyzing chamber attached with Keithley source meter. Since 3% Fe doped MoO3 sample displayed nano rods over the film surface which exhibits highest sensitivity of 38,500%, in a short period of raise and decay time 54 and 6 s. Our findings confirms that the 3% Fe doped MoO3 films suitability for ammonia gas sensing application.

14.
Biomater Sci ; 10(20): 5956-5967, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36043904

RESUMO

Lead-free halide perovskites have gained attention in recent years as viable materials with more distinctive characteristics than conventional semiconductor materials. Lead-free Cs3Bi2I9 colloidal perovskite nanocrystal is chosen to eliminate its single-phase synthesis difficulty and implement the material in bioimaging applications. Nanostructured Cs3Bi2I9 perovskite composites were coated with a thin coating of SiO2 by an in situ tetraethyl orthosilicate/(3-aminopropyl)trimethoxysilane injection growth method to enhance their stability in aqueous medium and biocompatibility. Single-phase novel Cs3Bi2I9 colloidal perovskite nanocrystal synthesis was successfully developed and optimized by adopting different synthetic conditions with varied experimental parameters. Characterization studies, including X-ray diffractometry and transmission electron microscopy, confirm the hexagonal structure of Cs3Bi2I9 crystals and their cubic morphology. A broad emission peak in the red region was captured for pure and composite perovskite under different excitation wavelengths and was observed using a UV-visible spectrophotometer. Bioimaging of Cs3Bi2I9@SiO2 composites incorporated with L929 cells was conducted using an inverted fluorescence microscope under blue and green excitation. The results obtained from bioimaging studies indicated that the Cs3Bi2I9@SiO2 nanocomposites entered the cell field and exhibited an emission under excitation. The non-toxic behavior of the synthesized Cs3Bi2I9@SiO2 composites was demonstrated using MTT cytotoxicity assay in L929 fibroblast mouse cells, showing better cell compatibility.


Assuntos
Nanocompostos , Nanopartículas , Animais , Compostos de Cálcio , Camundongos , Nanocompostos/química , Óxidos , Dióxido de Silício/química , Titânio
15.
Chemosphere ; 307(Pt 1): 135652, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35817189

RESUMO

Bismuth, a heavy metal which is found to be inexpensive and at a reduced cost, is utilized in the synthesis of different nanomaterials with novel structure, remarkable physical and chemical properties, adjustable bandgap, notable efficiency for photothermal conversion. These characteristics have made this element desirable for various applications such as storage and conversion of energy, electronics, sensors, photocatalysis, and other biomedical applications. These review papers are the vital points for the students, this report guides them to the research papers which focus on the impressive development in the area of bismuth and similar nanostructures. The purpose of the present review is to discuss the various synthesis routes of bismuth-based nanomaterials along with green synthesis, different nanostructures of bismuth, their significant properties, diverse applications and directions for the upcoming research. Therefore, with these different tuneable synthesis methods of bismuth-based nanomaterials combined with their novel properties, would elucidate on the future devices based on various nanostructures of bismuth.


Assuntos
Nanocompostos , Nanoestruturas , Bismuto/química , Humanos , Nanoestruturas/química , Fenômenos Físicos
16.
Sci Rep ; 12(1): 11572, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799052

RESUMO

In recent years, there has been an increase in demand for inexpensive biowaste-derived photocatalysts for the degradation of hazardous dyes and pharmacological drugs. Here, we developed eggshell derived hydroxyapatite nanoparticles entrenched on two-dimensional g-C3N4 nanosheets. The structural, morphological and photophysical behavior of the materials is confirmed through various analytical techniques. The photocatalytic performance of the highly efficient HAp/gC3N4 photocatalyst is evaluated against methylene blue (MB) and doxycycline drug contaminates under UV-visible light exposure. The HAp/gC3N4 photocatalyst exhibit excellent photocatalytic performance for MB dye (93.69%) and doxycycline drug (83.08%) compared to bare HAp and g-C3N4 nanosheets. The ultimate point to note is that the HAp/gC3N4 photocatalyst was recycled in four consecutive cycles without any degradation performance. Superoxide radicals play an important role in degradation performance, which has been confirmed by scavenger experiments. Therefore, the biowaste-derived HAp combined with gC3N4 nanosheets is a promising photocatalyst for the degradation of hazardous dyes and pharmacological drug wastes.


Assuntos
Corantes , Durapatita , Catálise , Doxiciclina , Luz , Azul de Metileno
17.
Polymers (Basel) ; 14(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35566911

RESUMO

Hybrid polymer films of polyvinyl pyrrolidone (PVP)/polyvinyl alcohol (PVA) embedded with gradient levels of Bi-powder were prepared using a conventional solution casting process. XRD, FTIR, and SEM techniques have been used to examine the micro/molecular structure and morphology of the synthesized flexible films. The intensities of the diffraction peaks and transmission spectrum of the PVP/PVA gradually declined with the introduction of Bi-metal. In addition, filler changes the microstructure surface of the pure film. The modification in the microstructure leads to an enhancement in the optical absorption characteristic of the blend films. The indirect allowed transition energy was calculated via Tauc's and ASF (Absorption Spectra Fitting) models. The decrease in the hybrid film's bandgap returns to the localized states in the forbidden region, which led the present films to be suitable for photo-electric, solar cell, etc., applications. The relation between the transition energy and the refractive index was studied. The enhancement in the refractive index with Bi-metal concentrations led to use the as-prepared films in optical sensors. The rise of Bi-metal concentrations leads also to the improvement of the nonlinear susceptibility and refractive parameters. The optical limiting characteristics revealed that the higher concentration dopant films reduce the light transmission intensity which is appropriate for laser attenuation and optical limiting in photonic devices. The results suggest that hybrid films are promising materials in a wide range of opto-electronic applications.

18.
Nanomaterials (Basel) ; 12(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35407178

RESUMO

The growth of the textile industry results in a massive accumulation of dyes on water. This enormous rise in pigments is the primary source of water pollution, affecting the aquatic lives and our ecosystem balance. This study aims to notify the fabrication of neodymium incorporated copper oxide (Nd2O3 doped CuO) nanoparticles by combustion method for effective degradation of dye, methylene blue (MB). X-ray diffraction (XRD), Field emission Scanning electron microscopy (FESEM), Zeta potential have been applied for characterization. Photocatalyst validity has been evaluated for methylene blue degradation (MB). Test conditions such as time of contact, H2O2, pH, and photo-Fenton have been modified to identify optimal degradation conditions. Noticeably, 7.5% Nd2O3 doped CuO nanoparticle demonstrated the highest photocatalytic efficiency, up to 90.8% in 80 min, with a 0.0227 min-1 degradation rate. However, the photocatalytic efficiency at pH 10 becomes 99% with a rate constant of 0.082 min-1. Cyclic experiments showed the Nd2O3 doped CuO nanoparticle's stability over repeated use. Scavenge hydroxyl radical species responsible for degradation using 7.5% Nd2O3 doped CuO nanoparticles have been investigated under visible irradiation.

19.
ACS Omega ; 7(15): 12716-12723, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35474841

RESUMO

Textile-based flexible and wearable electronic devices provide an excellent solution to thermal management systems, thermal therapy, and deicing applications through the Joule heating approach. However, challenges persist in designing such cost-effective electronic devices for efficient heating performance. Herein, this study adopted a facile solution-processed strategy, "dip-coating", to develop a high-performance Joule heating device by unformly coating the intrinsically conducting polymer (CP) poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) onto the surface of cotton textiles. The structural and morphological attributes of the cotton/CP mixture were evaluated using various characterization techniques. The electrothermal characteristics of the cotton/CP sample included rapid thermal response, uniform surface temperature distribution up to 94 °C, excellent stability, and endurance in heating performance under various mechanical deformations. The real-time illustration of the fabric heater affixed on a human finger has demonstrated its outstanding potential for thermal therapy applications. The fabricated heater may further expand it purposes toward deicing, defogging, and defrosting applications.

20.
J Mol Model ; 28(5): 112, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35378623

RESUMO

B3LYP, B97D, and M06-2X density functionals are utilized for probing the effect of decorating X (X = Co, Ti, Sc, or Ca) metals on the sensing performance of an aluminum phosphide nanotube (AlPNT) in detecting the hydrazine (HZ) gas. We predict that the interaction of pristine AlPNT with HZ is physisorption, and our calculated sensing response (SR) of AlPNT is approximately 2.7. The adsorption energy of HZ changes from - 4.6 to - 21.0, - 21.9, - 22.4, and - 23.8 kcal/mol by decorating the Co, Ti, Sc, and Ca metals into the AlPNT surface, respectively. Also, Co, Ti, Sc, and Ca rise the SR to 22.5, 36.8, 50.4, and 89.0, respectively, indicating that by increasing the atomic radius of metals, the sensitivity is more increased. So, we concluded that Ca much more increases the sensitivity of AlPNT toward HZ. Our calculations demonstrate that the electrostatic interaction has the main contribution in the formation of HZ/X decorated AlPNT (X@AlPNT) complexes. The expected recovery time is 22.0 s for the HZ desorption from the Ca@AlPNT at 298 K. Finally, we found that all of the X@AlPNTs have superior sensing performance toward HZ compared to the X@carbon nanotubes.


Assuntos
Nanotubos de Carbono , Compostos de Alumínio , Hidrazinas , Metais , Fosfinas
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