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Here, we report the effect of the substrate, sonication process, and postannealing on the structural, morphological, and optical properties of ZnO thin films grown in the presence of isopropyl alcohol (IPA) at temperature 30–65 °C by the successive ionic layer adsorption and reaction (SILAR) method on both soda lime glass (SLG) and Cu foil. The X-ray diffraction (XRD) patterns confirmed the preferential growth thin films along (002) and (101) planes of the wurtzite ZnO structure when deposited on SLG and Cu foil substrates, respectively. Both XRD and Raman spectra confirmed the ZnO and Cu-oxide phases of the deposited films. The scanning electron microscopy image of the deposited films shows compact and uniformly distributed grains for samples grown without sonication while using IPA at temperatures 50 and 65 °C. The postannealing treatment improves the crystallinity of the films, further evident by XRD and transmission and reflection results. The estimated optical band gaps are in the range of 3.37–3.48 eV for the as-grown samples. Our experimental results revealed that high-quality ZnO thin films could be grown without sonication using an IPA dispersant at 50 °C, which is much lower than the reported results using the SILAR method. This study suggests that in the presence of IPA, the SLG substrate results in better c-axis-oriented ZnO thin films than that of deionized water, ethylene glycol, and propylene glycol at the optimum temperature of 50 °C. Air annealing of the samples grown on Cu foils induced the formation of Cu x O/ZnO junctions, which is evident from the characteristic I–V curve including the structural and optical data.

Cuprous oxide (Cu2O) thin films have been grown on both soda lime glass (SLG) microscope slides and Fluorine-doped Tin Oxide (FTO) substrates by a modified SILAR technique. The pH level of the bath solution was systematically varied in the range of 4.50 – 7.95 to elucidate their effect on the physical properties of the deposited product. The prepared films showed compact surface morphology composed of spherical grains evident from their SEM images. The XRD measurement showed that the as-deposited films were single phase Cu2O with (111) preferred orientation and this texturing was found to be increasing with increasing pH and annealing temperature. The annealed Cu2O films were found to be stable up to 200 °C and completely converted to cupric oxide (CuO) phases when the temperature reached to 350 °C. The estimated optical bandgaps of the as-grown samples were found in the range of 2.28 – 2.48 eV using UV-Vis-NIR transmission data and showing a bandgap narrowing trend with the decreasing level of solution pH. The effect of post-annealing temperatures (75-350 0C) on the as-deposited films was also studied and found to be crucial to control the optical bandgap (1.44 – 2.13) eV and electrical properties of the films. The sheet resistance of the as-deposited samples was found to be decreasing from 4120 MΩ/square to 800 MΩ/square while grown with increasing acetic acid content in the precursor solutions and decreasing up to 2.66 MΩ/square while annealing up to 250 °C in the air.

We present a combined experimental and Hubbard interaction corrected density functional theory (DFT+U) based study of monoclinic scheelite (ms) bismuth vanadate BiVO4 (BVO). The ms-BVO samples were synthesized using the standard solid state reaction technique. The ms phase of the synthesized BVO samples has been confirmed from Rietveld analysis of the powder x-ray diffraction pattern and room temperature Raman spectroscopy. Both experimentally obtained crystal parameters and Raman peak positions were benchmarked against the DFT+U simulations. The variations in morphology and chemical concentrations due to different sintering temperatures and milling times were analyzed using field emission scanning electron microscopy and energy dispersive x-ray spectroscopy. The measured energy bandgap in the range of 2.38–2.58 eV from UV-Vis-NIR diffuse reflection spectroscopy was explained within the context of grain size variations in combination with bismuth and oxygen vacancies from DFT+U simulations.

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Herein, we have investigated the reinforcing potential of starch and cellulose pulp in a matrix of polyvinyl alcohol (PVA). Polyvinyl alcohol, starch, and pulp fibers having different compositions were constructed in order to achieve better reinforced composite films. Various techniques were utilized for extract the physical, mechanical as well as thermal properties. The magnitudes of tensile strength were reduced with rising of starch content in PVA. Tensile strength values of (PVA + starch) mixtures were enhanced with the enhancement of pulp fibers content. The properties of bulk density and water absorption revealed the significant impact of starch and pulp fibers. The obtained result of thermal stability of PVA was superior which was reduced by addition of starch content; therefore, regained with the insertion of pulp fibers content in PVA-starch matrix.

Oriented ZnO seed layers were deposited by three different techniques, namely, simple drop casting (DC), sol-gel derived dip coating (DPC) and spin coating of ball-milled ZnO powder solution(BMD) for the subsequent growth of vertically aligned ZnO nanorods along the substrate normal. X-ray diffraction (XRD) analyses revealed that ZnO(DC) seed layer exhibit the highest preferential c-axis texturing among the ZnO seed layers synthesized by different techniques. The Scanning Electron Microscopy (SEM) analysis evident that the morphology of ZnO seed layer surface is compact and coherently carpets the underlying substrate. ZnO nanorods(NRs) were then grown by hydrothermal method atop the ZnO seeded and non-seeded substrates grown by different techniques to elucidate the best ZnO seed layer promoting well-aligned ZnO Nanorods. The presence of c-axis oriented ZnO(DC) seeding layers was found to significantly affect the surface morphology and crystallographic orientation of the resultant ZnO NRs films. The optical band gap of ZnO(DC) seed and ZnO NRs were estimated to be 3.30 eV and in the range of 3.18 – 3.25 eV respectively by using UV-VIS-NIR diffuse reflection spectroscopy. The room temperature photoluminescence analyses revealed that nanostructured ZnO films exhibit a sharp near-band-edge luminescence peak at ∼380 nm consistent with the estimated optical band gap and the ZnO nanorod arrays are notably free from defect-related green-yellow emission peaks.

Spinel ferrite Ni[Formula: see text]Mn[Formula: see text]Zn[Formula: see text]Fe2O4 was prepared by a conventional ceramic process followed by sintering at three different temperatures (1050[Formula: see text]C, 1100[Formula: see text]C and 1150[Formula: see text]C). X-ray diffraction (XRD) investigations stated the single-phase cubic spinel structure and the FTIR spectra revealed two prominent bands within the wavenumber region from 600 cm[Formula: see text] to 400 cm[Formula: see text]. Surface morphology showed highly crystalline grain development with sizes ranging from 0.27 [Formula: see text]m to 0.88 [Formula: see text]m. The magnetic hysteresis curve at ambient temperature revealed a significant effect of sintering temperature on both coercivity ([Formula: see text] and saturation magnetization ([Formula: see text]. Temperature caused a decrease in DC electrical resistivity, while the electron transport increased, suggesting the semiconducting nature of all samples and that they well followed the Arrhenius law from which their activation energies were determined. The values of Curie temperature ([Formula: see text] and activation energy were influenced by the sintering temperature. Frequency-dependent dielectric behavior (100 Hz–1 MHz) was also analyzed, which may be interpreted by the Maxwell–Wagner-type polarization. The UV–vis–NIR reflectance curve was analyzed to calculate the bandgap of ferrites, which showed a decreasing trend with increasing sintering temperature.