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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]

• 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]

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]