Enhancing the optical properties of [P(MMA-co-AN)/ZrO2]TF by doping fluorescein dye, TD-DFT/DMOl3 simulations and COVID-19 main protease docking

Poly methyl methacrylate-co-acrylonitrile [P(MMA-co-AN)]HB hybrid blend was first synthesized by precipitation polymerization and characterized by static light scattering. With a thickness of 200 ± 5 nm, the hybrid nanocomposite of [P(MMA-co-AN)/ZrO2]HNC thin films were fabricated by spin coating method. X-Ray diffraction studies showed a monoclinic cell structure with an average crystalline size of 180 nm for the fabricated films. An improvement in the optical properties were figured out when fluorescein dye was doped in the hybrid nanocomposite. Where the optical energy gap was decreased from 4.31 to 4.025 eV for fluorescein doped hybrid nanocomposite. While a possible energy transfer between ZrO2 and fluorescein was investigated in the laser photoluminescence spectra. DFT-CASTEP simulations were deployed to calculate the theoretical optical properties for the molecules under consideration. The structural and optical simulations of [P(MMA-co-AN)/ZrO2]HNC were found to match the experimental data. Molecular docking studies of [P(MMA-co-AN)/ZrO2]Iso against the main protease of novel corona virus COVID 19 (PDB code 6LU7 Hormone) showed an interesting interaction.

Synthesis, electrospinning, and molecular docking of poly(methyl methacrylate) Schiff bases and their applications as polymeric antimicrobial agents and for dye removal

The antibacterial activity of a variety of modified poly(methyl methacrylate) Schiff bases against common microbial infections and removal of methylene blue (MB) dye were screened. The Schiff bases were synthesized from the reaction of the modified (PMMA) with vanillin (PMMA)Van and cinnamaldehyde (PMMA)Cin. By using Fourier transformer infrared (FT-IR), X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), the structures of the nanofibers of the synthesized Schiff bases were confirmed. The modified Kirky-Bauer method was used to screen the antibacterial activities of all the obtained materials against various bacterial species, including gram-positive bacterial (Bacillus subtilis (4k1p), Staphylococcus aureus), Gram-negative bacteria (Escherichia coli (7ab3), Pseudomonas aeruginosa). Inhibition zones against gram-positive bacteria ranged in diameter from 7 to 14 mm, whereas for the Gram-negative bacteria, the inhibition zones found to be ranged between 6 and 13 mm. With a minimum bactericidal concentration (MBC) of 8 mg/mL and a minimum inhibitory concentration (MIC) of 2 mg/mL, (PMMA)Van shown the greatest antibacterial activity. Lastly, molecular docking research was done to better understand the interactions between this series' targets and inhibitors for (PMMA)Van and (PMMA)Cin (4k1p and 7ab3). Molecular modeling of these surface-adsorbed polymers indicated that (PMMA)Van binds more strongly with Nitrogen than does (PMMA)Cin through extra hydrogen-bonding interactions. All the developed materials were evaluated for the removal of 0.1 g/L methylene blue dye (MB) from an aqueous solution. The elimination percentage of MB dye ranged from 26.67% by using 0.05 g powder of (PMMA)Cin to 85.63% by employing 0.05 g nanofibers of (PMMA)Van.

Study of the structural characteristics, optical properties, and electrical conductivity of doped [P(An-MMa)/ZrO2]TF nanofiber composite using experimental data and TD-DFT/DMol3 computations

The powder form of the new nanofiber composite of poly(acrylonitrile-co-methylmethacrylate) (P(An-MMa)) with zirconium dioxide (ZrO2) was synthesized using the sol-gel method and subsequently converted to a thin film [P(An-MMa)/ZrO2]TF via the physical vapor deposition (PVD) technique. Numerous characterization techniques, including Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and ultraviolet-visible (UV-Vis) optical spectroscopy, were used to characterize [P(An-MMa)/ZrO2]TF. Additionally, using density functional theory (DFT), optimization via time-dependent density functional theory (TD-DFT/DMol3) and Cambridge Serial Total Energy Bundle (TD-DFT/CASTEP) was developed. The TD-DFT calculations accurately matched the observed XRD and Raman spectra and validated the molecular structure of the examined materials. The average crystallite size of [P(An-MMa)/ZrO2]TF, as determined by XRD calculations, is 171.04 nm. The SEM image depicts a one-dimensional morphological structure made up of tightly packed fibrous nanowires or brushes. The optical properties of the films were determined using optical absorbance spectrophotometric results in the 200-850-nm wavelength range. The optical energy bandgaps computed using Tauc's equation for [P(An-MMa)/ZrO2]TF are 2.352 and 2.253 eV, respectively, whereas the isolated molecule of the composite [P(An-MMa)/ZrO2]Iso has a bandgap of 2.415 eV as determined by TD-DFT/DMol3. The optical characteristics predicted by CASTEP in TD-DFT are in good agreement with the experimental values. The investigated large optical energy bandgap nanofiber composite is advantageous for some energy storage applications.

A comparative study of Cu-anchored 0D and 1D ZnO nanostructures for the reduction of organic pollutants in water

In this work, Cu NPs were loaded at a fixed percentage (5 wt%) on 1D, (1D + 0D) and 0D ZnO nanostructures to investigate the effect of the support morphology on the reduction of organic pollutants in water. The synthesized materials were characterized by high-resolution transmission electron microscopy (HR-TEM), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption-desorption and X-ray photoelectron spectroscopy (XPS). The results reveal that the loading of Cu NPs decreases the optical band gap, and a slight change in the crystallite sizes increases the specific surface area value of the nanocomposites. The TEM images reveal that 1D ZnO has an average width of 44.7 nm and an average length of 211 nm, while 0D ZnO has an average diameter of 54.5 nm. The HR-TEM and XPS data confirm the loading of metallic Cu NPs on the surface of the ZnO nanostructures. The pure ZnO and nanocomposites were tested for 4-nitrophenol (4-NP) reduction in the presence of NaBH4 at room temperature. The obtained results show that pure ZnO nanostructures have no catalytic performance, while the nanocomposites showed good catalytic activities. The catalytic reduction efficiency of 4-NP was found to follow the order of Cu/0DZnO > Cu/(1D + 0D)ZnO > Cu/1DZnO. The complete reduction of 4-NP has been observed to be achievable within 60 s using the Cu/0DZnO nanocomposite, with a k app value of 8.42 min-1 and good recyclability of up to five cycles. This nanocomposite was then applied in the reduction of organic dyes in water; it was found that the reduction rate constants for the methylene blue, Congo red, and acriflavine hydrochloride dyes were 1.4 min-1, 1.2 min-1, and 3.81 min-1, respectively. The high catalytic performance of this nanocomposite may be due to the small particle size, high specific surface area, and the high dispersion of Cu NPs on the surface of ZnO.

Kinetics and Mechanism Studies of Oxidation of Dibromothymolsulfonphthalein Toxic Dye by Potassium Permanganate in Neutral Media with the Synthesis of 2-Bromo-6-isopropyl-3-methyl-cyclohexa-2,5-dienone

The oxidation of 3',3″-dibromothymolsulfonphthalein (DBTS) in neutral medium by potassium permanganate multi-equivalent oxidant has been studied spectrophotometrically. Pseudo-first-order plots showed inverted S-shape throughout the entire course of the reaction. The initial rates were found to be relatively fast in the early stages, followed by a decrease in the oxidation rates over longer time periods in the slow stage. Under pseudo-first-order conditions where [DBTS] ≫ 10 [MnO₄ ^-], the experimental results showed a first-order dependence in [MnO₄ ^-] and fractional-first-order kinetics in the [DBTS] concentration. The formation of 1:1 coordination intermediate complex prior to the rate-determining step was revealed kinetically. In addition, the intermediate species involving complexes of Mn(V) coordination has been detected. The oxidation product of DBTS was identified by Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, and gas chromatography-mass analysis. The obtained results indicated the formation of 2-bromo-6-isopropyl-3-methyl-cyclohexa-2,5-dienone as a derivative oxidation of DBTS.

Fabrication and Characterization of Polypyrrole/Multi-Walled Carbon Nanotubes Thin Films Using Thermal Evaporation

Polypyrrole/multiwalled carbon nanotubes composites (PPy/MWCNTs) were produced in an acidic solution utilizing an in situ oxidative polymerization method using ferric chloride as an oxidizing agent and sodium dodecyl sulfate as a soft template. Thermal evaporation was used to fabricate thin films from polypyrrole/multiwalled carbon nanotube composites. The resulting composites were examined by different techniques to explore their morphology, structural and electrical characteristics. The surface morphology analysis revealed that polypyrrole structure is a two-dimensional film with impeded nanoparticles and the thickness of coated PPy around the MWCNTs decreases when increasing the amount of MWCNTs. XRD analysis revealed that the average crystallite size of the prepared composites is 62.26 nm. The direct energy gap for PPy is affected by a factor ranging from 2.41 eV to 1.47 eV depending on the contents of MWCNTs. The thin film's optical properties were examined using experimental and TDDFT-DFT/DMOl³ simulation techniques. The optical constants and optical conductivity of the composites were calculated and correlated. The structural and optical characteristics of the simulated nanocomposites as single isolated molecules accord well with the experimental results. The nanocomposite thin films demonstrated promising results, making them a viable candidate for polymer solar cell demands. Under optimal circumstances, the constructed planar heterojunction solar cells with a 75 ± 3 nm layer of PPy/MWCNTs had a power conversion efficiency (PCE) of 6.86%.

Thermal Analysis of a Metal-Organic Framework ZnxCo1-X-ZIF-8 for Recent Applications

Zeolitic imidazolate frameworks (ZIFs) are interesting materials for use in several aspects: energy storage material, gas sensing, and photocatalysis. The thermal stability and pyrolysis process are crucial in determining the active phase of the material. A deep understanding of the pyrolysis mechanism is in demand. Therefore, the thermodynamics and combustion process with different heating rates was examined, and the kinetic parameters were computed employing thermogravimetric tests. Based on the TG analysis of combustion, pyrolysis moves to the high-temperature region with an increase in heating rate. The decomposition process can be separated into the dehydration (300-503 K) and the pyrolysis reaction (703-1100 K). Three points of the decomposition process are performed by dynamical analysis owing to shifts of slopes, but the combustion process has only one stage. The Zeolitic imidazolate framework's structure properties were examined using TDDFT-DFT/DMOl3 simulation techniques. Dynamical parameters, for instance, the possible mechanism, the pre-exponential factor, and the apparent activation energy are obtained through comparison using the Kissinger formula. The thermodynamics analysis of the Zn1-xCox-ZIF-8 materials is an effective way to explore the temperature influence on the process of pyrolysis, which can benefit several environment purifications, photocatalyst, and recent applications.

Experimental characterization, TDDFT-DFT, and spin effect on [PEG/H2O–ZrO2/TiO2]h hybrid nanofluid 3D flow as potential ceramic industry application

Doped zirconium oxide nanoparticles [ZrO2]NPs in the [PEG–H2O] and [TiO2]NPs in the [PEG–H2O/ZrO2]C matrices to fabricated the [PEG–H2O/ZrO2+TiO2]h hybrid nanofluid films by a sol–gel method, the average crystallite size is 100 ± 5 nm. The nanofluid and hybrid nanofluid thin films are studied using combined experimental and DFT theoretical method (DMOl3), including FTIR spectrum and optical properties. Mathematically, Higher rate of reactions of rotating [PEG/H2O–ZrO2]m, and [PEG–H2O/ZrO2+TiO2]h nanofluids on an extending sheet is considered with thermal radiation and heat source. The numerical Runge–Kutta–Fehlberg of 4–5th order (RKF45) method is used to solve the issue. The results specifically determine that Δ E g Opt ${\Delta}{E}_{g}^{\text{Opt}}$ values decrease from 2.27 eV for [PEG–H2O/ZrO2]m mono nanofluid to 1.596 eV for [PEG–H2O/ZrO2+TiO2]h hybrid nanofluid using the DFT computations HOMO and LUMO calculation. This result concluded that the [PEG–H2O/ZrO2]m transformed from semiconductor to [PEG–H2O/ZrO2+TiO2]h as a superconductor hybrid nanofluid by addition [TiO2]NPs. The hybrid nanoparticles have a higher influence than nanoparticles on the velocity distributions.