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1.
Carbohydr Polym ; 339: 122263, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823927

RESUMEN

Photochromic wood materials are very important and appealing for smart windows. Herein, we describe the development of transparent photochromic wood that can change its color under ultraviolet and visible lights. Photoluminescent transparent wood was prepared by delignification of wood followed by infiltration with a combination of gum Arabic/chitosan/acrylic acid (ACA), lanthanide-activated aluminum strontium oxide (LASO) as a photoluminescent, and Genipin as a cross-linking agent. The produced mixture was then infused into the lignin-modified wood substrate. In order to develop a luminescent colorless wood, the LASO phosphor must be well-distributed in the ACA solution without aggregation. According to the colorimetric parameters and photoluminescence spectra, this optically active wooden window switched color from transparent in daylight to green when UV-irradiated. Transmission electron microscopy (TEM) was employed to examine the morphological features of phosphor nanoparticles. The morphological features of the developed smart wooden window were investigated by scanning electron microscopy (SEM), X-ray fluorescent spectroscopy (XRF), and energy-dispersive X-ray analyzer (EDX). The mechanical performance was explored by investigating both hardness and resistance to scratches. The luminescent woods displayed an emission band at 518 nm when excited at 365 nm. The superhydrophobic performance and ultraviolet shielding of woods were improved upon increasing the phosphor content.

2.
Int J Biol Macromol ; 273(Pt 2): 133226, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38889827

RESUMEN

Multifunctional transparent woods have recently attracted a great interest as efficient products for many applications, such as smart window and smart packaging. Herein, a transparent wood with several desirable properties, including flame-retardant activity, ultraviolet shielding, superhydrophobicity, good roughness, durability and photostability was developed. The current photoluminescent wood showed a remarkable capacity to keep releasing light in the dark for extended durations. Multifunctional transparent wood was prepared by infiltrating a delignified wooden bulk with a combination of polyvinyl alcohol (PVA), ammonium polyphosphate (APP), cellulose nanocrystals, and rare-earth strontium aluminate nanoparticles (RSAN). Cellulose nanocrystals were prepared from microcrystalline cellulose, and used as reinforcement nanofiller to enhance the mechanical strength of the polyvinyl alcohol matrix and a dispersant agent to avoid agglomeration of RSAN. RSAN displayed diameters of 8-16 nm, while cellulose nanocrystals displayed lengths of 75-150 nm and diameters of 5-10 nm. According to photoluminescence spectra and the colorimetric space coordinates reported by the CIE Lab parameters, the transparent wood changed color to bright green when exposed to UV irradiation. For the produced phosphorescent wood surfaces, an absorption band was detected at 365 nm to generate an emission band at 519 nm.


Asunto(s)
Celulosa , Nanocompuestos , Nanopartículas , Alcohol Polivinílico , Madera , Celulosa/química , Nanocompuestos/química , Madera/química , Alcohol Polivinílico/química , Nanopartículas/química , Fenómenos Mecánicos , Rayos Ultravioleta
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124497, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-38795527

RESUMEN

Smart packaging materials have been used to protect human health from environmental hazards by sending real-time colorimetric signals for changes in the food packaging environment. However, the colorimetric material sensors use synthetic sensor dyes, which are toxic, expensive, non-biodegradable, and difficult to prepare. Herein, a simple strategy is presented for the development of an environmentally-friendly halochromic wood able to change color upon exposure to spoilage of food. A combination of anthocyanin (Ac)/aluminum (Al) mordant (Ac/Al) nanoparticles and cellulose nanowhiskers (CNW)-reinforced polyvinyl alcohol (PVA) was infiltrated into a delignified wood to produce a translucent wood with halochromic properties. CNW were employed as reinforcement agent to improve the mechanical performance of PVA. Additionally, CNW function as a dispersing agent to prevent agglomeration of Ac/Al nanoparticles. The diameters of CNW are in the range of 12-19 nm, whereas Ac/Al particles showed diameters of 9-22 nm. The smart wood changed color from purplish to colorless when exposed to food spoilage. A hypsochromic change from 539 nm to 370 nm was shown by the anthocyanin receptor when the spoilage level of food increased. This could be attributed to the pH-driven molecular switching of anthocyanin, leading to charge delocalization.


Asunto(s)
Antocianinas , Celulosa , Embalaje de Alimentos , Alcohol Polivinílico , Madera , Antocianinas/química , Antocianinas/análisis , Celulosa/química , Alcohol Polivinílico/química , Madera/química , Embalaje de Alimentos/métodos , Colorimetría/métodos , Nanopartículas/química , Color , Tecnología Química Verde/métodos
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124397, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38718744

RESUMEN

Smart polymer glue with photoluminescence and water-repellent properties was developed. The luminescent adhesive continues emitting light for up to 120 min after turning the excitation source off. Nanoparticles of lanthanide strontium aluminum oxide (LSAO) (8-13 nm) were consistently immobilized into carboxymethyl cellulose-reinforced gum Arabic (CMC/GA) adhesive. Using various concentrations of LSAO, the generated adhesives showed emission intensity at 519 nm and an excitation band at 365 nm. Depending on LSAO content, both of afterglow and fluorescence emission were monitored. Photochromism was detected as the transparent adhesive film changes color to green under ultraviolet irradiation. A greenish-yellow lightening in a darkened place was also observed. The nanocomposite resistance to scratches and hydrophobicity were found to enhance as the LSAO content was increased in the carboxymethyl cellulose-reinforced gum Arabic matrix. The LSAO@CMC/GA nanocomposite showed high durability and photostability. The present strategy proved the viability of a potential mass production toward photoluminescent adhesives for various smart applications, such as smart packaging, anti-counterfeiting printing, smart windows, and safety signs.

5.
Int J Biol Macromol ; 267(Pt 2): 131649, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636751

RESUMEN

The colorless ammonia gas has been a significant intermediate in the industrial sector. However, prolonged exposure to ammonia causes harmful effects to organs or even death. Herein, an environmentally friendly solid-state ammonia sensor was developed utilizing colorimetric polycaprolactone-co-polylactic acid nanofibrous membrane. Pomegranate (Punica granatum L.) peel contains anthocyanin (ACN) as a naturally occurring spectroscopic probe. A mordant (potassium aluminum sulfate) is used to immobilize the anthocyanin direct dyestuff inside nanofibers, generating mordant/anthocyanin (M/ACN) coordinated complex nanoparticles. When exposed to ammonia, the color change of anthocyanin-encapsulated polycaprolactone-co-polylactic acid nanofibrous membrane from purple to transparent was examined by absorbance spectra and CIE Lab color parameters. With a quick colorimetric shift, the polycaprolactone-co-polylactic acid fabric exhibits a detection limit of 5-150 mg/L. The absorbance spectra showed a hypsochromic shift when exposed to ammonia, displaying an absorption shift from 559 nm to 391 nm with an isosbestic point of 448 nm. Scanning electron microscopy (SEM) images revealed that the polycaprolactone-co-polylactic acid nanofibers had a diameter of 75-125 nm, whereas transmission electron microscopy (TEM) images revealed that M/ACN nanoparticles exhibited diameters of 10-20 nm.


Asunto(s)
Amoníaco , Antocianinas , Nanofibras , Poliésteres , Nanofibras/química , Poliésteres/química , Antocianinas/química , Amoníaco/química , Amoníaco/análisis , Gases/química , Colorimetría
6.
Int J Biol Macromol ; 264(Pt 2): 130766, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462101

RESUMEN

An inorganic/organic nanocomposite was used to develop an afterglow and color-tunable smart window. A combination of polylactic acid (PLA) plastic waste as an environmentally-friendly hosting agent, and lanthanide-activated strontium aluminum oxide nanoparticles (SAON) encapsulated with silica nanoparticles (SAON@Silica) as a photoluminescent efficient agent resulted in a smart organic/inorganic nanocomposite. In order to prepare SAON-encapsulated silica nanoparticles (SAON@Silica), the SAON nanoparticles were coated with silica using the heterogeneous precipitation method. By using transmission electron microscopy (TEM), SAON showed a diameter range of 5-12 nm, while the SAON@Silica nanoparticles showed a diameter range of 50-100 nm. In order to ensure the development of a colorless plastic film, a homogeneous dispersion of the phosphorescent Phosphor@Silica nanoparticles throughout the plastic bulk was confirmed. CIE Lab coordinates and luminescence spectra were used to study the color shift characteristics. Under visible light conditions, the plastic films were transparent. The photoluminescent films emitted green light at 525 nm when excited at 375 nm. The hydrophobicity and ultraviolet protection were enhanced without altering the fundamental physico-mechanical performance of the plastic sheet. The current color-tunable plastic can be used in many potential applications, such as warning signs, anti-counterfeiting barcodes, smart windows, and protective apparel.


Asunto(s)
Metales de Tierras Raras , Nanopartículas , Dióxido de Silicio , Poliésteres , Óxido de Aluminio , Aluminio
8.
Luminescence ; 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38088104

RESUMEN

Polyester textiles have been applied in numerous industrial applications. Polyester fibers are characterized with being excellent insulators to electricity, having excellent flexural and impact strength, ease of manufacture, low-cost, as well as having resistance to moisture and chemicals. However, polyester fibers cannot be stained due to the absence of active dyeing sites on the surface of the fibrous structure. Thus, polyester cannot be dyed after it has been extruded. Herein, we report the development of novel-colored polyester fabrics using plasma-assisted dyeing and anthocyanin natural probe for determination of ammonia that may cause severe harmful effects to human organs and even death. Anthocyanin was extracted from red cabbage and characterized. The water-soluble anthocyanin was fastened to polyester fibers by mordant (potash alum) to generate anthocyanin-mordant coordinative complex nanoparticles. Polyester can be treated with thin layer of anthocyanin probe after activation with plasma. The results showed excellent colorfastness, ultraviolet blocking, and antibacterial performance of the anthocyanin-dyed polyester (APET) fibers. The APET fibers showed great potential for developing a portable colorimetric device for an on-site detection of ammonia. APET displayed a detection limit of aqueous ammonia in the range of 25-200 ppb, displaying a change in color from purple (542 nm) to white (387 nm).

9.
Environ Technol ; : 1-23, 2023 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-37953534

RESUMEN

ABSTRACTResearch efforts are focusing on investigating cost-effective and ecologically friendly ways to create nanoparticles as a result of promising developments in green technology (NPs). This experiment focused on the effectiveness of using biochar (TWB) made from coffee waste to extract levofloxacin (LEV) from water. The conclusive results of the trials showed that TWB is an effective adsorbent for removing LEV from liquid solutions. The TWB produced through biological processes underwent comprehensive analysis using techniques such as X-ray diffractometry (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area measurement (BET), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. The bioengineered TWB's exceptional crystalline properties, which closely resemble the monoclinic structure of bulk TWB, were confirmed by the XRD analysis. Based on the scanning electron microscopy (SEM) data, the synthesis of TWB Nanoparticles resulted in the formation of spherical particles with an approximate diameter of 40 nm, accompanied by a substantial surface area of 285.55 m²/g. The Pseudo-Second-Order model, which best captured Levofloxacin's adsorption characteristics, was evaluated on the TWB, and the results showed that external mass transfer was the main determinant of response rate. It was also found that the adsorption process was endothermic and spontaneous. The system was optimized using the Box-Behnken design (BBD) methodology. The achieved removal capacity of 1119.19 mg/g utilizing the tested adsorbent was determined to be reasonable when compared to the performance of other previously used adsorbents when evaluating the effectiveness of eliminating LEV. The process of LEV adsorption onto TWB involves a number of different mechanisms, such as ion exchange, π-π interactions, electrostatic pore filling, and hydrogen bonding. Following extensive testing in connection with a real-world sample, the adsorbent demonstrated remarkable efficacy, and it maintained good performance even after undergoing three further regeneration cycles. By adjusting the annealing temperature, we controlled the synthesis of TWB nanoparticles across a range of sizes in order to maximize their antibacterial capabilities. This research utilized a pair of Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and a pair of Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate the antibacterial efficacy of TWB.


Green synthesis of biochar via using tea waste.Adsorption studies of harmful pesticides Levofloxacin (LEV).The adsorbents exhibited good reusability for four adsorption/desorption cycles.Adsorption fit with pseudo second order kinetics and Langmuir isotherm model.The adsorption fitted to pseudo-second-order kinetically.This system will provide helpful guidance for coloured effluent treatment.Optimized the results by using Box-Behnken design.

10.
ACS Omega ; 8(35): 32130-32145, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37692223

RESUMEN

Eliminating pesticides is essential for lowering the dangers to our environment. To do this effectively, it is crucial to find adsorbents with remarkable adsorption capacities, easy retrieval, and separation. Metal-organic frameworks (MOFs) have been extensively recognized for their exceptional ability to absorb pollutants. Therefore, we used novel lanthanum metal-organic frameworks (La-MOFs) to eliminate deltamethrin (DEL) from aqueous solutions. We proved through experimentation that the La-MOF is an efficient adsorbent for DEL from water. A study of the material revealed that the adsorbent had a surface area of 952.96 m2 per gram and a pore volume of 1.038 cm3/g. These outcomes show how this substance can absorb particles. Utilizing kinetic models and conforming to the pseudo-second-order model, a thorough analysis of the efficiency of DEL adsorption onto La-MOF was conducted. To create a perfectly tailored approach, we utilized many parameters. The synthetic La-MOF adsorbent may undergo up to five steps of adsorption-desorption and has exceptional cyclability and reusability. To confirm purifying wastewater samples in the laboratory, the presentation of the established adsorbent was evaluated. For the management of industrial effluent and water filtration, the La-MOF adsorbent offered a simple and effective solution. Our investigation suggests that the method we describe for removing DEL from wastewater samples using the La-MOF adsorbent is unique.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123063, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37390719

RESUMEN

The target of the current study is to create a novel hybrid nanocomposite (Cs@Pyc.SOF) by combining the anti-hepatitis C virus (HCV) drug sofosbuvir with the nano antioxidant pycnogenol (Pyc) and nano biomolecules like chitosan nanoparticles (Cs NPs). The characterization procedure works to verify the creation of nanocomposite (NCP) using several different techniques. UV-Vis spectroscopy is used to measure SOF loading efficiency. The various concentrations of the SOF drug were used to determine the binding constant rate Kb, which was found to be 7.35 ± 0.95 min-1 with an 83% loading efficiency. At pH 7.4, the release rate was 80.6% after two hours and 92% after 48 h, whereas at pH 6.8, it was 29% after two hours and 94% after 48 h. After 2 and 48 h, the release rate in water was 38% and 77%, respectively. . The SRB technique for fast screening is used for the cytotoxicity test, where the investigated composites show a safety status and high viability against the examined cell line. The cytotoxicity assay of the SOF hybrid materials has been identified with cell lines like mouse normal liver cells (BNL). So, Cs@Pyc.SOF was recommended as a substitute medication for the therapy of HCV, but the results need clinical studies.


Asunto(s)
Quitosano , Hepatitis C , Animales , Ratones , Sofosbuvir , Antivirales/uso terapéutico , Hepacivirus , Preparaciones Farmacéuticas , Quimioterapia Combinada , Hepatitis C/tratamiento farmacológico , Análisis Espectral , Ribavirina
12.
ACS Omega ; 8(19): 16956-16965, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37214711

RESUMEN

ß-Cyclodextrin (CD) is currently exploited for the implantation of lipophobic polymer dots (PDs) for antimicrobial and anticancer laborers. Moreover, the PDs were investigated to act as a chemo-sensor for metal detection. The data revealed that under basic conditions, photoluminescent PDs (5.1 nm) were successively clustered with a controllable size at 190 °C, whereas under acidic conditions, smaller-sized non-photoluminescent carbon nanoparticles (2.9 nm) were obtained. The fluorescence intensity of synthesized PDs under basic conditions was affected by pH, and such an intensity was significantly higher compared to that prepared under acidic conditions. The PDs were exploited as florescent detectors in estimation of Ag+ ions in aquatic streams. Treatment of Ag+ ion colloids with PDs resulted in fluorescence quenching attributing to the production of AgNPs that approved by spectral studies. The cell viability percent was estimated for Escherichia coli, Staphylococcus aureus, and Candida albicans after incubation with PDs implanted under basic conditions for 24 h. The cell mortality percent was estimated for breast cancer (MCF-7) after incubation with different concentrations of PDs that were implanted under acidic versus basic conditions to show that treatment of the tested cells with 1000 µg/mL PDs prepared under basic (IC50 232.5 µg/mL) and acidic (IC50 88.6 µg/mL) conditions resulted in cell mortality percentages of 70 and 90%, respectively.

13.
Int J Biol Macromol ; 238: 124028, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-36924871

RESUMEN

Fluorescent inks have been emerged as a desirable encoding technique to enhance anticounterfeiting printing of commercial goods. However, significant drawbacks with fluorescent inks, such as poor durability, low efficiency, and high cost. Herein, we describe the preparation of a self-healing authentication ink based on carboxymethyl cellulose (CMC) hydrogel immobilized with nitrogen-doped carbon dots (NCD) nanoparticles (NPs) for cutting-edge anticounterfeiting applications. Security inks that self-heal are very durable. Under ambient conditions, the prepared NCD@CMC hydrogel could self-heal with a high healing efficiency. It might stick to diverse surfaces such as plastic, glass and paper sheets. The self-healing composite ink demonstrated outstanding photostability under UV light. Straightforward and environmentally friendly method was applied on the agricultural waste of rice straw toward the production of NCD using hydrothermal carbonization in an aqueous medium, and in the presence of NH4OH as an inexpensive passivating agent. The quantum yield (QY) for NCD reached 24.09 %. Various concentrations of NCD NPs were employed to produce self-healable nanocomposite inks with a variety of emission properties. Stamping homogeneous films onto paper surfaces produced a transparent layer. The CIE Lab and emission spectra of prints independently verified the capability of NCD nanocomposite inks to vary their color to blue under UV illumination. To measure the particle diameter of the prepared NCD, their morphological characteristics were examined by transmission electron microscopy (TEM) to indicate diameters of 10-25 nm. Utilizing various analytical techniques, the morphology and chemical composition of the fluorescent prints were examined. We examined the mechanical qualities of the stamped papers as well as the rheological characteristics of the ink hydrogel. Due to their colorless appearance, the excitation band of the printed films was peaked at 364 nm, while their emission was peaked at 465 nm. The current smart ink holds high potential for numerous applications like smart packaging and authentication, and shows great promise as a practical and mass production approach for easily creating anticounterfeiting stamps.


Asunto(s)
Carboximetilcelulosa de Sodio , Hidrogeles , Carboximetilcelulosa de Sodio/química , Carbono/química , Colorantes , Rayos Ultravioleta
14.
Environ Sci Pollut Res Int ; 30(22): 62676-62688, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36947383

RESUMEN

Simple and green strategy was described for the development of multifunctional polyester nanofibers (PNFs). Solution blow spinning (SBS) technology was applied to in situ immobilize nanocomposites of polyaniline (PANi) and silver nanoparticles (AgNPs) into plasma-treated polyester nanoscaled fibers prepared. The polyester nanofibers were prepared from recycled polyethylene terephthalate waste, which was exposed plasma-curing and a REDOX reaction in the presence of AgNO3, aniline, and CH3COONH4. Plasma-catalyzed oxidative polymerization of aniline to polyaniline together with a reductive process of Ag+ to silver nanoparticles led to their enduring insoluble dispersion into the surface of polyester nanofibers. By taking the advantage of the PANi oxidation, AgNPs were precipitated from an aqueous medium of AgNPs. The morphological properties were investigated by various analytical techniques. The polyester fiber diameter was determined in the range of 450-650 nm. In addition, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were utilized to examine AgNPs, demonstrating diameters of 4-20 nm. The plasma-uncured AgNPs/PANi immobilized nanofibrous film displayed weak absorption bands at 399 nm and 403 nm upon increasing the concentration of AgNPs. On the other hand, the plasma-cured AgNPs/PANi immobilized nanofibers displayed strong absorption bands at 526 nm and 568 nm upon increasing the concentration of AgNPs. The AgNP-induced antimicrobial performance and the PANi-induced electrically conductivity were explored. The prepared PNFs showed high UV protection.


Asunto(s)
Nanopartículas del Metal , Nanofibras , Plata/farmacología , Tereftalatos Polietilenos , Compuestos de Anilina , Oxidación-Reducción
15.
RSC Adv ; 13(10): 6466-6480, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36860528

RESUMEN

As their manufacturing and consumption have increased, pharmaceutical chemicals have increasingly been found in wastewater. It is necessary to look into more effective methods, including adsorption, because current therapies can't completely eliminate these micro contaminants. This investigation aims to assess the diclofenac sodium (DS) adsorption onto an Fe3O4@TAC@SA polymer in a static system. Through Box-Behnken design (BBD), system optimization was carried out, and the ideal conditions - adsorbent mass of 0.01 g and agitation speed of 200 rpm - were chosen. The adsorbent was created utilizing X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), allowing us to gain a comprehensive understanding of its properties. The analysis of the adsorption process revealed that the external mass transference was the primary rate-controlling step, and the Pseudo-Second-Order model demonstrated the best correlation to kinetic experimental results. An endothermic, spontaneous adsorption process took place. The removal capacity was 858 mg g-1, which is a respectable result when compared to other adsorbents that have been utilized in the past to remove DS. Ion exchange, π-π interactions, electrostatic pore filling and hydrogen bonding all play a role in the adsorption of DS on the Fe3O4@TAC@SA polymer. After careful examination of the adsorbent towards a true sample, it was determined to be highly efficient after three regenerative cycles.

16.
ACS Omega ; 8(5): 5042-5049, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36777607

RESUMEN

The present study introduced the construction and electroanalytical characterization of novel tirofiban (TIR) carbon paste voltammetric sensors integrated with copper oxide nanoparticles. The copper oxide nanostructure remarkably enhanced the oxidation of TIR molecules on the electrode surface with an irreversible anodic oxidation peak at about 1.18 V. The peak current values of the recorded differential pulse voltammograms were correlated to the TIR concentrations within a defined linear range from 0.060 to 7.41 µg mL-1 with an LOD value of 20.7 ng mL-1. Based on the electrochemical behavior of TIR at different scan rates and with the aid of the molecular orbital calculations performed on the TIR molecule, the electro-oxidation reaction was postulated to undergo through the oxidation of the five-membered-ring nitrogen atom with the transfer of one electron and one proton. Based on the reported selectivity and sensitivity of the proposed method, TIR was successfully determined in Aggrastat intravenous infusion and biological samples with mean average recoveries agreeable with the UV spectrophotometric method.

17.
ACS Omega ; 7(23): 19454-19464, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35721986

RESUMEN

Linen has been a significant material for textile packaging. Thus, the application of the simple spray-coating method to coat linen fibers with a flame-retardant, antimicrobial, hydrophobic, and anticounterfeiting luminescent nanocomposite is an innovative technique. In this new approach, the ecologically benign room-temperature vulcanizing (RTV) silicone rubber was employed to immobilize the environmentally friendly Exolit AP 422 (Ex) and lanthanide-doped strontium aluminum oxide (RESAO) nanoscale particles onto the linen fibrous surface. Both morphological properties and elemental compositions of RESAO and treated fabrics were examined by transmission electron microscopy (TEM), scanning electron microscopy (SEM), wavelength-dispersive X-ray fluorescence (WD-XRF), Fourier transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray spectroscopy (EDX). In the fire resistance test, the treated linen fabrics produced a char layer, giving them the property of self-extinguishing. Furthermore, the coated linen samples' fire-retardant efficacy remained intact after 35 washing cycles. As the concentration of RESAO increased, so did the treated linen superhydrophobicity. Upon excitation at 366 nm, an emission band of 519 nm was generated from a colorless luminescent film deposited onto the linen surface. The coated linen displayed a luminescent activity by changing color from off-white beneath daylight to green beneath UV source, which was proved by CIE Lab parameters and photoluminescence spectral analysis. The photoluminescence effect was identified in the treated linen as reported by emission, excitation, and decay time spectral analysis. The comfort properties of coated linen fabrics were measured to assess their mechanical and comfort features. The treated linen exhibited excellent UV shielding and improved antimicrobial performance. The current simple strategy could be useful for large-scale production of multifunctional smart textiles such as packaging textiles.

18.
Microsc Res Tech ; 85(7): 2607-2617, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35373877

RESUMEN

Anticounterfeiting of commercial products has been improved using photochromism as an intriguing approach. In order to develop a mechanically reliable nanocomposite, the engineering procedure of the anticounterfeiting nanocomposite must be improved. Rare-earth doped aluminate/polypropylene (REA/PP) hybrid nanofibers were successfully made by electrospinning, and they were shown to be mechanically stable and highly photoluminescent, making them ideal for anticounterfeiting applications. UV-induced photochromic anticounterfeiting properties were monitored in the synthesized nanocomposite films. In order to ensure that the REA-PP film is completely transparent, REA must be embedded into the polypropylene nanofibers in nano-sized particle shape to facilitate a better dispersion without agglomeration of REA particles in polypropylene matrix. The morphology and structure of REA were studied by transmission electron microscopy and X-ray diffraction. The morphologies and chemical contents of the polypropylene nanofibrous films were studied by scanning electron microscopy, X-ray fluorescence, and energy-dispersive X-ray spectroscopy. The REA-PP nanofibrous film showed absorbance and emission maxima at 365 and 517 nm, respectively. When exposed to UV light, the photochromic activity of the transparent nanofibrous substrates to greenish-yellow was rapid and reversible without fatigue. Hydrophobicity of REA-PP films increased without affecting their original look or mechanical properties, while increasing the REA content. It was possible to produce ultraviolet-induced photochromic nanofibrous films that were transparent, flexible, and cost-effective. As a result of this method, numerous anticounterfeiting materials could be developed toward a better marketplace with both economy and community values. HIGHLIGHTS: Rare-earth aluminate/polypropylene (REA/PP) electrospun nanofibers were prepared. The photochromic transparent nanofibers displayed green emission under UV light. The nanofibrous films were flexible, mechanically stable and highly luminescent. Films showed absorbance and emission maxima at 365 and 517 nm, respectively. Hydrophobicity was improved without affecting the films original properties.

19.
ACS Omega ; 7(12): 10599-10607, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35382282

RESUMEN

A simple inorganic/organic nanocomposite was used to generate long-lasting phosphorescent pebbles for easy commercial manufacturing of smart products. An organic/inorganic nanocomposite was made from low-molecular-weight unsaturated polyester and rare-earth-activated strontium aluminum oxide nanoparticles doped with europium and dysprosium. The polyester resin was mixed with phosphorescent strontium aluminate oxide nanoparticles and methylethyl ketone peroxide as a cross-linking agent to create a viscous mixture that can be hardened in a few minutes at room temperature. Before adding the hardener catalyst, the phosphorescent strontium aluminate nanoparticles were dispersed throughout the polyester resin in a homogeneous manner to ensure that the pigment did not accumulate. Long-lasting, reversible luminescence was shown by the photoluminescent substrates. The emission was reported at 515 nm upon exciting the pebble at 365 nm. In normal visible light, both blank and luminescent pebbles had a translucent appearance. As a result of UV irradiation, the photoluminescent pebbles produced an intense green color. The three-dimensional CIE Lab (International Commission on Illumination) color coordinates and luminescence spectra were used to investigate the color changing characteristics. Photophysical characteristics, including excitation, emission, and lifetime, were also investigated. Scanning electron microscopy, wavelength-dispersive X-ray fluorescence spectroscopy, and energy-dispersive X-ray analysis were employed to report the surface morphologies and elemental content. Without impairing the pebbles' original physico-mechanical characteristics, the pebbles showed improved superhydrophobic activity. The current simple colorless long-lasting phosphorescent nanocomposite can be applied to a variety of surfaces, like ceramics, glassware, tiles, and metals.

20.
Environ Sci Pollut Res Int ; 29(40): 60173-60188, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35419683

RESUMEN

Sugarcane bagasse agricultural waste has been one of the most common solid pollutants worldwide. Thus, introducing a simple method to convert sugarcane bagasse into value-added materials has been highly significant. Herein, we develop a simple and green strategy to reprocess sugarcane bagasse as a starting material for the preparation of graphene oxide nanosheets toward the preparation of novel photoluminescent, hydrophobic, and anticorrosive epoxy nanocomposite coatings integrated with lanthanide-doped aluminate nanoparticles. Environmentally friendly graphene oxide (GO) nanostructures were provided by a single-step preparation procedure from sugarcane bagasse (SCB) agricultural waste using ferrocene-based oxidation under muffled conditions. The oxidized SCB nanostructures were applied as a drier, anticorrosion, and crosslinking agent for epoxy coatings. Different concentrations of pigment phosphor were applied onto the epoxy coating. The generated epoxy-graphene-aluminate (EGA) paints were then coated onto mild steel. The hydrophobic properties and hardness as well as resistance to scratch of the EGA paints were examined. The transparency and colorimetric screening of the EGA nanocomposite paints were determined by the absorption spectral analysis and CIE Lab parameters. The luminescent translucent paints demonstrated a bright green emission at 520 nm when excited at 372 nm. The anticorrosion properties of the painted steel submerged in NaCl(aq) were inspected by the electrochemical impedance spectral (EIS) method. The EGA paints with phosphor (11% w/w) exhibited the most distinct anti-corrosion properties and long-persistent luminescence. The produced paints displayed high durability and photostability.


Asunto(s)
Grafito , Nanocompuestos , Saccharum , Celulosa/química , Grafito/química , Pintura , Saccharum/química , Acero
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