Wound healing is a topic of significant interest in current times, owing to the escalating incidence of chronic diseases associated with impaired healing, as well as the growing number of elderly ...individuals within the population. Amongst the various approaches for fabrication of wound healing dressings, the utilization of selenium‐based nanoparticles has garnered considerable attention due to selenium's numerous advantages, including antioxidant, antiviral, antibacterial, and antifungal activities. With this perspective, we focused on the fabrication and characterization of hydrogels incorporated with selenium nanoparticles (SeNPs). In this work, we have developed a microwave‐assisted hydrothermal synthesis strategy for synthesis of the SeNPs that employ non‐toxic precursors, thereby reducing the risk of environmental toxicity and providing a cost‐effective alternative to conventional chemical and hydrothermal methods. Subsequently, we have successfully incorporated SeNPs into hyaluronic acid methacrylate/gelatin methacrylate‐based hydrogels. Hyaluronic acid and gelatin are selected to support the healing process further, and these polymers are methacrylated in order to further control mechanical properties of the hydrogel and improve the stability of the dressing. The nanoparticles and the nanoparticle‐incorporated hydrogels were characterized by various techniques including Fourier transform infrared spectroscopy, UV–Vis spectroscopy, scanning electron microscopy, and dynamic light scattering instruments. Mechanical behaviors, swelling and degradation properties of the dressings were evaluated. Afterwards, we have conducted cell culture studies with SeNPs‐loaded hydrogels to determine the efficacy of SeNPs in wound healing. According to experimental findings, in vitro scratch assay suggests that a hydrogel dressing containing SeNPs (HG‐SeNp2) support the cell migration more compared to other samples incorporated with nanoparticles and to the control study at 24 h, and the wound closure percentage was found to be statistically significant compared with the control study. This dressing hold promise as effective wound dressings that can facilitate and expedite the process of wound healing.
Selenium nanoparticles (SeNPs) are the valuable elements in wound healing applications.
An easy microwave‐assisted hydrothermal method was utilized for synthesizing SeNPs.
SeNPs were embedded into hydrogel wound dressings to better support the healing process.
Molybdenum disulfide (MoS2) nanoflowers consisting of hybridized 1T/2H phases have been synthesized by using a microwave‐assisted hydrothermal (MTH) method. The concentration of the 1T phase, ranging ...from 40 % to 73 %, is controlled by simply adjusting the ratio of the Mo and S precursors. By using the hybridized 1T/2H MoS2 as an electrode material, it was demonstrated that the resulting supercapacitor performance is dominated by the 1T phase concentration. It was found that a supercapacitor with 73 % 1T phase exhibits excellent capacitance of 259 F g−1 and great cyclic stability after 1000 cycles. The formation mechanism of the MHT‐synthesized hybridized 1T/2H MoS2 is also reported. More importantly, the mechanism also explains the observed relationship between the 1T phase concentration and the ratio of the Mo and S precursors.
Molybdenum disulfide (MoS2) nanoflowers consisting of hybridized 1T/2H phases have been synthesized by using a microwave‐assisted hydrothermal (MTH) method. The concentration of the 1T phase, ranging from 40 % to 73 %, is controlled by simply adjusting the ratio of the Mo and S precursors. The resulting supercapacitor performance using the hybridized 1T/2H MoS2 as an electrode material is dominated by the 1T phase concentration.
Nd3+,Y3+ codoped CaF2 nanoparticles (NPs) have been synthesized by a microwave-assisted hydrothermal method, using citrate moiety as capping agent. Y3+ ions have been introduced in the crystal ...structure to declusterize the Nd3+ ions and improve the emission properties. After a structural and morphological characterization of the obtained NPs, the optical properties of colloidal dispersions have been analyzed in the near infrared (NIR) range. The emission spectra reveal several transitions associated with different sites where the Nd3+ ions are accommodated in the crystal structure. Some bands show a marked dependence on the temperature, and a thermometric investigation reveals good thermal relative sensitivities in the physiological temperature range (20–60 °C), proving the applicability of the investigated colloidal NPs as optical nanothermometers.
•CaF2:Nd3+,Y3+ nanoparticles are prepared by a MW assisted hydrothermal method.•Water colloidal dispersions are very stable.•Optical thermometry is evaluated in the 1st and 2nd biological windows using Nd3+ emissions.•Very good relative thermal sensitivities are found.
Niobium pentoxide (Nb2O5) was synthesized by the microwave-assisted hydrothermal method using two different niobium precursors: niobium ammoniacal oxalate (P1) and niobium chloride (P2). The XRD ...result confirms the presence of Nb2O5 with low crystallinity for both precursor samples. The SEM images show differences between the material morphologies but with the same aggregation particle characteristics. Photocatalytic degradation of the rhodamine B (RhB) dye was performed using both samples of Nb2O5 as a photocatalyst under UVC illumination using a 24 factorial design experimental method. The studied variables were the type of precursor (P1 and P2), the RhB concentration (1 × 10−5 and 3 × 10−5 M), the Nb2O5 photocatalyst dosage (25 and 50 mg), and the time of the photocatalysis analysis (30 and 60 min), verifying the influence on the RhB dye removal efficiency. The factorial design showed that all variables had a significant effect on the process, but the variables with the most influence were RhB concentration and photocatalysis time. For both precursors, the samples that showed greater removal efficiency were those under conditions 1 × 10−5 M, 50 mg, and 60 min, obtaining 92.87% and 98.99%, respectively. The high rate of RhB removal suggests that the Nb2O5 obtained by microwave-assisted hydrothermal synthesis has the potential to be used in photocatalytic processes to remove organic pollutants from effluents.
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•ZnSnO3 was fabricated by a microwave-assisted hydrothermal method and calcination.•ZnSnO3 presented a nanocubic and porous structure.•Porous ZnSnO3 nanocubes presented sensitivity ...and selectivity to triethylamine.•High response and fast response time toward triethylamine detection were attained.•The sensor showed a low detection limit (∼0.6 ppm) to triethylamine detection.
Triethylamine (TEA), a volatile organic compound (VOC), is present in several industrial processes and is harmful to human health. Therefore, the development of highly sensitive TEA sensors is desirable. Semiconductor metal oxides (SMOx) have been widely used for VOCs detection due to their efficiency and feasibility. Herein, we report the template-free synthesis of zinc stannate nanocubes (NC-ZnSnO3) by the microwave-assisted hydrothermal method followed by a calcination step. The sample's sensing properties were investigated for different VOCs (methanol, ethanol, isopropanol, acetic acid, acetone, 2-butanone, acetaldehyde, benzene, toluene, m-xylene, and TEA). The sensor presented an improved selectivity toward TEA, showing the highest response of 57.5 to 100 ppm of TEA with a fast response time of 4 s at the optimum operating temperature of 350 °C. The NC-ZnSnO3 also showed a low detection limit for TEA of about 0.6 ppm. In summary, this work described an efficient method for producing NC-ZnSnO3 and demonstrated that this material has high selectivity and sensitivity for TEA detection.
Silver vanadate (Ag3VO4) is considered one of the most important semiconductors. It finds practical applications in electrochemical cells, as bactericidal and virucidal agents, in photocatalysis, and ...environmental remediation. Despite the impressive experimental progress, the dependence of the properties of a material is strongly linked to its chemical composition and structure. In this sense, the peculiar physical-chemical properties of the vanadate's class have become important. However, the fundamentals of structure in this material remain poorly understood, and the theoretical insight into the morphology linked to its properties is completely missing. In the present study, different synthesis times were tested in the obtention of Ag3VO4 crystals by the microwave-assisted hydrothermal method, and their properties were discussed based on experimental results and quantum mechanics simulations. Structural characterizations (XRD, Raman and UV–vis spectroscopy, FE-SEM, and TEM analyses) confirmed the material order at short, medium, and long-range. Theoretical calculations contributed to identifying the atom distribution in the structure, nature of the type of electronic transition, and density of states present in the valence and conduction bands. The topological analysis of the electron density indicated transit chemical interactions and unexpected argentophilic interactions, and Mulliken, Hirshfeld and Bader population analysis provided the charges present on the chemical elements of the crystal. Predicted theoretical surface shapes and their stabilities were evaluated along with FE-SEM images.
This work reports the microstructural (XRD/SEM), dilatometric and electrical characterization (impedance spectroscopy) of ceria (CeO2) obtained by microwave-assisted hydrothermal synthesis under mild ...conditions (T = 120 °C and short reaction times of 10 and 20 min). The as-prepared and calcined powders show characteristic diffraction peaks of the cubic fluorite-type structure of cerium oxide. A remarkable sinterability allows obtaining dense ceramics (relative densities exceeding 95%) with enhanced electrical properties (σt = 2.14 × 10−5 S cm−1 at 500 °C) after sintering at a temperature as low as 1200 °C.
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•CeO2 synthesized under mild conditions of temperature and reaction time.•Highly dense ceramics at low processing temperatures.•Enhanced ionic conductivity with respect to commercial material.
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•Different amount of Cu or Mn doped TiO2 were synthesized and used as photoanode in DSSCs.•1,10-phenanthroline and Cu, Mn, Cr-1,10-phenanthroline complexes were used as dyes.•0.5% and ...1% Cu or Mn doped TiO2 were increased the efficiency of solar cells.•When doping amount reached 2%, efficiency of solar cells decreased.
The effects of the concentrations of different metal dopants on TiO2 and different metal 1,10-phenanthroline (Phen) complexes on dye sensitized solar cells (DSSCs) yield were investigated. TiO2 were doped with Cu or Mn by different percentages (0.5%, 1%, 2%). Undoped and doped TiO2 nanoparticles were synthesized via microwave assisted hydrothermal method and these nanoparticles were used as photoanode by coating FTO glass by spin coater. Synthesized samples were characterized with SEM, EDS, XRD, DRS. DSSCs were prepared with photoanodes which have doped TiO2 nanoparticles as active layer. These photoanodes were sensitized with Phen. Also for comparing, different metal (Cu, Mn or Cr)-Phen complex dyes were used with undoped TiO2, 1% Cu doped TiO2 and 1% Mn doped TiO2 photoanodes. Prepared solar cells were characterized with linear sweep voltammetry and electrochemical impedance spectroscopy. While N719 sensitized 0.5% and 1% Cu or Mn doped TiO2 have more solar conversion efficiency than 2% doped Cu or Mn and undoped TiO2, all Cu or Mn doped TiO2 photoanodes have more efficiency except 2% doped Mn doped TiO2 than undoped TiO2 photoanode when sensitized with Phen by using interaction of Cu or Mn ions with Phen.
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•Microwave-assisted hydrothermal method is used to prepare phase pure anatase TiO2.•TiO2 particles are nanosized and mesoporous in nature.•TiO2 particles exhibited very high N2 ...adsorption capacity.•Photodegradation efficiency of 98% was achieved in degrading methylene blue dye using TiO2 particles.
Among the different polymorphs of TiO2, the anatase form has the highest photocatalytic activity. However, preparing anatase TiO2 typically requires long reaction times, high pressures, or both. Therefore, it is important to develop easy and quick methods to prepare anatase TiO2. In these lines, an easy microwave-assisted hydrothermal method is used in this work to prepare mesoporous and phase pure anatase TiO2 nanospheres (ATNS) with an average crystallite size of ∼ 10 nm. Titanium butoxide and methanol are used as the precursor and solvent, respectively, to prepare ATNS. Due to its moderate loss tangent value of ∼ 0.659, methanol aids in the efficient absorption of microwaves and rapid local heating for the reaction to complete quickly, leading to the formation of TiO2 nanospheres with mesoporosity, a high specific surface area of 60.46 m2/g, and a high N2 adsorption capacity. ANTS photodegrade methylene blue dye with an efficiency as high as 98 %. The enhanced intrinsic photocatalytic activity of ATNS is attributed to the combined effect of mesoporosity, high specific surface area, and high N2 adsorption capacity.
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•A new bismuth molybdate β(L)-Bi2Mo2O9 has been discovered and its structure solved.•This phase appears to be a low temperature polymorphic form of β-Bi2Mo2O9.•It is stable up to ...532 °C where it transforms to the know high temperature form.•Tested in propene oxidation, it is as active and selective as α-Bi2Mo3O12.
A new bismuth molybdate, obtained by means of microwave-assisted hydrothermal synthesis, is described by the chemical formula: β(L)-Bi2Mo2O9, in accordance with its low crystallization temperature and transition to β-Bi2Mo2O9 at 532 °C. Its structure, solved ab initio using powder diffraction data, crystallizes in the monoclinic system (space group P21/c), with a = 8.11413(5), b = 8.54445(5), c = 13.43623(6) Å, and β = 123.5085(2)°. This phase has been tested as a catalyst for the oxidation of propene. It appears to be highly stable on stream, with a specific rate of propene conversion comparable to that of α-Bi2Mo3O12 and a slightly higher selectivity to acrolein. A possible active site for the abstraction of the first hydrogen from propene has been identified, by analogy with that proposed for α-Bi2Mo3O12 and seems to correspond to a molybdenyl Mo = O oxygen that is weakly coordinated to a neighboring Bi cation.
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