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Ce, Cu co-doped ZnS nanoparticles were prepared at room temperature using a chemical co-precipitation method. The prepared nanoparticles were characterized by X- ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive analysis of X-rays (EDAX), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and high resolution Raman spectroscopic techniques. Transmission electron microscopy (TEM) and X-ray diffraction studies showed that the diameter of the particles was around 2–3 nm. Broadened XRD peaks revealed the formation of nanoparticles with a face centered cubic (fcc) structure. DRS studies confirmed that the band gap increased with an increase in the dopant concentration. The Raman spectra of undoped and Ce, Cu ions co-doped ZnS nanoparticles showed longitudinal optical mode and transverse optical mode. Compared with the Raman modes (276 and 351 cm −1 ) of undoped ZnS nanoparticles, the Raman modes of Ce, Cu co- doped ZnS nanoparticles were slightly shifted towards lower frequency. PL spectra of the samples showed remarkable enhancement in the intensity upon doping. [ABSTRACT FROM AUTHOR]

In this work, we have investigated on Lantana camara mediated silver nanoparticles (AgNPs) with different leaf extract (LE) quantity for the evaluation of efficient bactericidal activity. The AgNPs were prepared by simple, capable, eco-friendly and biosynthesis method using L. camara LE. This method allowed the synthesis of crystalline nanoparticles, which was confirmed by X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns. The X-ray photoelectron spectroscopy (XPS) analysis confirmed the formation of metallic silver and elucidates the surface state composition of AgNPs. UV–vis spectra of AgNPs and visual perception of brownish yellow color from colorless reaction mixture confirmed the AgNP formation. Involvement of functional groups of L. camara leaf extract in the reduction and capping process of nanoparticles was well displayed in Fourier transform infrared spectroscopy (FTIR). Decrement of particle size with an increment of leaf extract volume was evident in AFM, TEM images and also through a blue shift in the UV–vis spectra. The rate of formation and size of AgNPs were dependent on LE quantity. Meanwhile, these AgNPs exhibited effective antibacterial activity with the decrement of particle size against all tested bacterial cultures. [ABSTRACT FROM AUTHOR]

Zirconium oxide (zirconia) powder has been synthesized by co-precipitation method. The structural characterization of prepared sample was obtained by X-ray diffraction and showed monoclinic phase. Further surface morphology was confirmed by scanning electron microscopy (SEM). The frequency dependence of dielectric constant, dielectric loss, and impedance of the sample was investigated at room temperature. The obtained results partially motivated for alternative silicon based on devices. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nearly spherical Ag NPs are prepared using P. amboinicus leaf extract. [•] The green synthesis route is simple, nontoxic, reliable and eco-friendly benign. [•] XRD and SAED patterns attested the crystalline nature of the samples. [•] Biomolecules of the leaf extract play dual role as both reducing and capping agents. [•] It exhibited effective antimicrobial efficacy against E. coli and Penicillium spp. [Copyright &y& Elsevier]

Highlights: [•] NiO–Ag films were deposited using DC reactive magnetron sputtering technique. [•] Surface morphology was highly influenced by reactive gas of oxygen. [•] The resistivity values exhibited a decreasing tendency with partial pressure of oxygen. [•] The electrical properties of p-NiO films were enhanced by Ag doping. [ABSTRACT FROM AUTHOR]

• Nanostructured WO 3 thin films were prepared by electron beam evaporation. • The gas sensing measurements were evaluated towards different operating temperatures, different gases and different concentrations. • When the substrate temperature increased to 100 °C, grain size of the film increased and nanorods appeared and possess a very high surface to volume ratio. • The films deposited at substrate temperature of 100 °C shows high response value of 58 towards ethanol gas. In the recent years, metal oxide semiconductors such as SnO 2 , CuO, Fe 2 O 3 , TiO 2 , WO 3 and ZnO were investigated for the detection of ethanol gas in the environment. Among these, WO 3 is one of the best n-type semiconductor material for ethanol gas detection. In this paper, nanostructured WO 3 thin films were prepared by electron beam evaporation on glass substrate and investigated their ethanol gas sensing properties. Surface morphology, structural and elemental analysis of the WO 3 thin films were analysed by scanning electron microscopy (SEM), atomic microscopy (AFM), X-ray diffraction and X-ray photoelectron spectroscopy. The as deposited films exhibited nanostructure and highly influenced by the substrate temperature. From the X-ray photoelectron spectroscopy analysis, we found that substrate temperature increases the binding energy shift in lower energy regions and shows that WO 3 films contain oxygen vacancies. The gas sensor sensitivities were measured for different gases with different concentrations at various operating temperatures. The obtained results show that the nanostructure WO 3 films are suitable sensing material for ethanol gas. The nanostructure WO 3 films deposited at substrate temperature of 100 °C shows best sensitivity with quick response and recovery time, which is attributed to the formation of nanorods and possess a very high surface to volume ratio. [ABSTRACT FROM AUTHOR]

Abstract: Nickel oxide thin films of various thicknesses were grown on glass substrates by dc reactive magnetron sputtering technique in a pure oxygen atmosphere with sputtering power of 150 W and substrate temperature of 523 K. Crystalline properties of NiO films as a function of film thickness were investigated using X-ray diffraction. XRD analysis revealed that (200) is the preferred orientation and the orientation of the films changed from (200) to (220) at film thickness of 350 nm. The maximum optical transmittance of 60% and band gap of 3.82 eV was observed at the film thickness of 350 nm. The lowest electrical resistivity of 5.1 Ω cm was observed at a film thickness of 350 nm, thereafter resistivity increases with film thickness. [Copyright &y& Elsevier]

Abstract: Nickel oxide (NiO) thin films were prepared on glass substrates at various bias voltages using dc reactive magnetron sputtering technique. The influence of substrate bias voltage on structural, optical and electrical properties was systematically investigated using X-ray diffraction (XRD), SEM, EDS, spectrophotometer and Hall effect studies. The NiO films are crystalline with preferential growth along (200) plane. The NiO films exhibit optical transmittance of 55% and direct band gap of 3.78eV at the substrate bias voltage of −75V. The electrical resistivity decreases as substrate bias voltage increases from 0 to −75V thereafter it was slightly increased. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of cadmium indate were deposited onto the glass substrates by employing dc magnetron sputtering from cadmium–indium alloy target under various substrate temperatures in the range 373–673K. The films were characterized by studying their structural and electrical properties. The films formed at substrate temperature <423K were amorphous while those deposited at ≥423K were polycrystalline with cubic spinel structure. The films prepared at a substrate temperature of 673K exhibited low electrical resistivity of 3.5×10−4 Ωcm and Hall mobility of 29cm2/Vs. [Copyright &y& Elsevier]

Abstract: Cadmium indate films were deposited by dc reactive magnetron sputtering onto glass substrates in an oxygen partial pressure of 5×10−4 mbar and at various substrate temperatures in the range 373–673 K. The influence of substrate temperature on the structural, electrical and optical properties of the films was systematically studied. The films formed at substrate temperatures <423 K were amorphous while those deposited at ≥423 K were polycrystalline with cubic spinel structure. The decrease of electrical resistivity and increase of Hall mobility with the increase of substrate temperature were due to the improvement in the crystallinity of the films. The temperature dependence of Hall mobility measurements indicated that the grain boundary scattering of charge carriers was predominant in the films. The films formed at a substrate temperature of 673 K exhibited an electrical resistivity of 3.5×10−4 Ω cm, Hall mobility of 29 cm2 V−1 s−1, optical transmittance of 88%, optical band gap of 3.28 eV and figure of merit of 5×10−2 Ω−1. [Copyright &y& Elsevier]

Optical absorption studies on vacuum flash evaporated polycrystalline Cu0.5Ag0.5InSe2 thin films are reported. The absorption humps observed in the spectra are attributed to transitions from the valence sub-bands to the conduction band. From the optical transmittance data, the optical band gap energies, spin–orbit and crystal-field parameters are determined. [Copyright &y& Elsevier]

Graphical representation of NiO, NCO and NCO/NiO NFs synthesization. [Display omitted] • NCO/NiO NFs, nanocomposites were synthesized via a facile electrospun and solvothermal method for a future electrode material of supercapacitor. • The NCO/NiO NFs having quick signal transfer in gas sensing and have high specific capacitance (1007 Fg−1) and good cyclic performance (92%). • Ammonia gas sensing performance of NCO/NiO NFs was measured, and the fast response and recovery times were found and are 32 s and 34 s, respectively. • NCO/NiO NFs nanocomposite materials could be utilized for constructing of good solid-state supercapacitors and gas sensing devices. In the present study, we investigated the NiCo 2 O 4 /NiO (NCO/NiO) composite nanofibers (NFs) synthesized via a facile electrospinning and solvothermal method as a future electrode material. The synthesized samples are characterized and their electrochemical and gas sensing properties are investigated. The morphology, structural, asymmetric vibrations and elemental compositions in the prepared samples are studied by Field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Raman spectroscopy, Energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The prepared NCO/NiO NFs exhibit high specific capacitance (1212 Fg−1) and good cyclic performance (94%), showing promising supercapacitor properties. For NCO/NiO NFs, the continuity of the structure contributes to rapid signal transmission in gas detection. Ammonia gas measurement of NCO/NiO NFs operated at 100 °C showed fast response and recovery times of 17 and 11 s, respectively. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been synthesized by Lantana camara leaf extract through simple green route and evaluated their antibacterial and catalytic activities. The leaf extract (LE) itself acts as both reducing and stabilizing agent at once for desired nanoparticle synthesis. The colorless reaction mixture turns to yellowish brown attesting the AgNPs formation and displayed UV–Vis absorption spectra. Structural analysis confirms the crystalline nature and formation of fcc structured metallic silver with majority (1 1 1) facets. Morphological studies elicit the formation of almost spherical shaped nanoparticles and as AgNO 3 concentration is increased, there is an increment in the particle size. The FTIR analysis evidences the presence of various functional groups of biomolecules of LE is responsible for stabilization of AgNPs. Zeta potential measurement attests the higher stability of synthesized AgNPs. The synthesized AgNPs exhibited good antibacterial activity when tested against Escherichia coli , Pseudomonas spp., Bacillus spp. and Staphylococcus spp. using standard Kirby–Bauer disc diffusion assay. Furthermore, they showed good catalytic activity on the reduction of methylene blue by L. camara extract which is monitored and confirmed by the UV–Vis spectrophotometer. [ABSTRACT FROM AUTHOR]

Abstract: Nanoparticles of Zinc sulfide co-doped with equal atomic percentages of Mn and Te (5, 10 and 15at%) were synthesized for the first time by chemical co-precipitation method. Thiophenol was used to passivate the surface of the particles. The as-prepared samples were amorphous in nature and nano-crystallinity was induced after calcining at 300°C/2h. The nanoparticles were characterized by EDAX, XRD, TEM, optical absorption and PL studies. EDAX spectra revealed only minor deviations of the dopant concentrations from the target compositions. The nanoparticles showed cubic structure. The particle size estimated from XRD/TEM was in the range 3–5nm. Optical absorption studies showed a blue-shift of the fundamental absorption edge with respect to that of bulk ZnS. PL spectra showed emission in the red region with composition dependent emission wavelength. ZnS nanoparticles doped with Mn (5 and 10at%) were also synthesized and characterized for comparison. [Copyright &y& Elsevier]

Ni-Cu-Zn ferrite materials have been extensively used in multilayer chip inductors because of their remarkable properties at higher frequencies. In the present work, single phase Ni0.35Cu0.05Zn0.60Fe1.98O4-δ ferrite, has been prepared by microwave sintered (MS) method. In comparison with the conventional sintering method (CS), the sintering temperature and time for this MS method were significantly reduced to 30 min and 950°C from 5 h and 1250°C for the CS process. The frequency dependence of the dielectric properties such as dielectric constant (ε'), dielectric loss (tan δ) were studied. The temperature dependence of magnetic initial permeability (μi) was studied. The saturation magnetization was also studied as a function of magnetic field. These microwave sintered ferrites results were compared with the properties of ferrites prepared by conventional sintering method in normal heating. Microwave sintering improves structural as well as electromagnetic parameters measured and thus makes the ferrite more suitable in microwave applications and electromagnetic devices. [ABSTRACT FROM AUTHOR]

Abstract: The optically transparent conducting molybdenum-doped indium oxide thin films (In2O3:Mo) were prepared on glass substrates by an activated reactive evaporation method and the influence of molybdenum doping levels on the electrical and optical properties of the films had been investigated systematically. The films, synthesized at a substrate temperature of 573K and a Mo-doping level of 3at.%, exhibited a minimum electrical resistivity of 5.2×10−4 Ωcm and an average optical transmittance of 90% in the visible region with a band gap of 3.68eV. [ABSTRACT FROM AUTHOR]

Abstract: Mo-doped In2O3 thin films have been prepared on glass substrates using an activated reactive evaporation method and systematically studied the effect of oxygen partial pressure on the structural, optical, electrical and photoluminescence properties of the films. The obtained films are highly transparent and conductive. The films exhibited the lowest electrical resistivity of 5.2×10−4 Ωcm, with an average optical transmittance of 90% in the visible region. An intensive photoluminescence emission peaks were observed at 415 and 440nm. [Copyright &y& Elsevier]

Abstract: Nanostructured Zn1− x Mn x S films (0⩽ x ⩽0.25) were deposited on glass substrates by simple resistive thermal evaporation technique. All the films were deposited at 300K in a vacuum of 2×10−6 m bar. All the films temperature dependence of resistivity revealed semiconducting behaviour of the samples. Hot probe test revealed that all the samples exhibited n-type conductivity. The nanohardness of the films ranges from 4.7 to 9.9GPa, Young’s modulus value ranging 69.7–94.2GPa. [Copyright &y& Elsevier]

Abstract: Transparent and high conductive molybdenum doped indium oxide (IMO) thin films have been deposited on glass substrates by activated reactive evaporation. The effect of substrate temperature on the structure, surface morphology, electrical, optical and photoluminescence properties of these films were systematically examined and it was found that crystallinity and growth orientation of the films were significantly influenced by substrate temperature. In addition the films exhibited a low electrical resistivity of 5.2×10−4 Ωcm with an optical transmittance 90% in the visible region of the solar spectrum at a substrate temperature of 573K. Intensive blue PL bands at 415 and 440nm were observed in the photoluminescence spectrum at room temperature. [Copyright &y& Elsevier]

Abstract: Nanocrystalline films of Cd1−x Mn x S (0≤ x ≤0.5) with grain size of 36–58nm were deposited on glass substrates at a substrate temperature of 300K using resistive thermal evaporation. All the films exhibited wurtzite structure and the lattice parameters varied linearly with composition. The magnetic susceptibility increased sharply with Mn content ‘x’ and decreased with increase of the temperature. [Copyright &y& Elsevier]

Nanocrystalline Zn1-xMnxS films (x=0.04, 0.08 and 0.12) were deposited on glass substrates at 400 K using a simple resistive thermal evaporation technique. All the deposited films were characterized by chemical, structural, morphological, optical and magnetic properties. Scanning electron microscopy and atomic force microscopy studies showed that all the films investigated were in nanocrystalline form with the grain size lying in the range 10–20 nm. All the films exhibited cubic structure and the lattice parameters increase linearly with composition. The absorption edge shifted from the higher-wavelength region to lower wavelengths with increase in Mn concentration. The magnetization increased sharply with increase of the Mn content up to x=0.08 and then decreased with further increase of the Mn content. Particularly, Zn0.92Mn0.08S concentration samples show a weak ferromagnetic nature, which might be the optimum concentration for optoelectronic and spintronic device applications. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of Cd1−x Mn x S () were formed on glass substrates by resistive vacuum thermal evaporation. All the films were deposited at 300 K and the films were annealed at 373, 473 and 573 K for 1 h in a vacuum of 10−6 mbar. Atomic force microscopy (AFM) studies showed that all the films investigated were in nano-crystalline form with a grain size in the range 36–82 nm. All the films exhibited a wurtzite structure of the host material. The lattice parameters varied linearly with composition following Vegard’s law in the entire composition range. Photoluminescence studies showed that two distinct emission bands were observed for each Cd1−x Mn x S compound. One corresponds to internal transition and the other one is due to the transition of Mn2+ ions in interstitial sites or in small ‘Mn’ chalcogenic clusters. [Copyright &y& Elsevier]

Abstract: Thin films of cuprous oxide (Cu2O) were deposited on glass substrates at various bias voltages using DC reactive magnetron sputtering technique. The effects of substrate bias voltage on structural, electrical and optical properties were systematically analyzed. The crystallographic structure and orientation of the crystallites were strongly influenced by the bias voltage. [Copyright &y& Elsevier]