Optical and magnetic properties of Fe-doped CdS dilute magnetic semiconducting nanorods

Solvothermal technique has been used for the synthesis of Fe-doped CdS nanorods (Cd_1?xFe_xS) with (x = 0.0, 0.3, 0.5, 1.0, 1.5). Structural analysis carried out using X-ray diffraction reveals the formation of defect-free hexagonal phase of the CdS nanorods. Energy dispersive X-ray analysis confirms the presence of elements Cd, Fe and S in their stoichiometric ratio. Blue shift in the band gap, as compared to the bulk CdS, has been observed in UV–visible spectra. The decrease in the intensity of the photoluminescence peaks confirms the quenching of spectra upon Fe doping. Transmission electron microscopy, high-resolution transmission electron microscopy and selected area diffraction studies confirm the polycrystalline nature as well as growth of CdS nanorods along (112) plane. Magnetic study confirms the ferromagnetic nature of the synthesized nanorods. Magnetic saturation has been found to be 0.187, 0.300, 0.450, 0.675, 0.600 emu g^?1, respectively, for undoped, 3, 5, 10, and 15 % Fe-doped CdS.     

Effect of Ni-doping on optical and magnetic properties of solvothermally synthesized ZnS wurtzite nanorods

In this study we have reported the effect of Ni-doping on optical and magnetic properties of ZnS nanorods. The diameter and length of low temperature solvothermally synthesized, high quality nanorods are 10 and 50–300 nm respectively as revealed from transmission electron microscopy. From X-ray diffraction, the structure of Ni-doped nanorods was observed as wurtzite with lattice parameters, a = 3.83 and c = 6.26. The band gap of the undoped and doped samples was found to be blue shifted as compared to the bulk counterpart when analyzed with UV–visible spectroscopy. Quenching in photoluminescence spectra was observed in case of Ni-doped nanorods as compared to undoped counterpart. The magnetization as analyzed from vibrating sample magnetometer was found to increase with 1 and 5 % Ni-doping concentration, and decrease with further increase in Ni-doping concentration, i.e., with 10 % Ni-doping.     

Growth and characterizations of dual ion beam sputtered CIGS thin films for photovoltaic applications

The growth of CIGS thin films on soda-lime glass substrates at different substrate temperatures by dual ion beam sputtering system in a single-step route from a single quaternary sputtering target with the composition of Cu (In_0.70 Ga_0.30) Se₂ was reported. The effects of the substrate temperature on structural, optical, morphological and electrical properties of CIGS films were investigated. Stoichiometry of one such film was investigated by X-ray photoelectron spectroscopy. All CIGS films had demonstrated a strong (112) orientation located at 2θ ~26.70^o, which indicated the chalcopyrite structure of films. The value of full-width at half-maximum of (112) peak was reduced from 0.58° to 0.19° and crystallite size was enlarged from 14.98 to 43.05 nm as growth temperature was increased from 100 to 400 °C. However, atomic force microscope results showed a smooth and uniform surface at lower growth temperature and the surface roughness was observed to increase with increasing growth temperature. Hall measurements exhibited the minimum film resistivity of 0.09 Ω cm with a hole concentration of 2.42 × 10¹⁸ cm^?3 and mobility of 28.60 cm² V^?1 s^?1 for CIGS film grown at 100 °C. Film absorption coefficient was found to enhance nominally from 1 × 10⁵ to 2.3 × 10⁵ cm^?1 with increasing growth temperature from 100 to 400 °C.     

Effect of stabilizer on structural, optical and electrochemical properties of sol–gel derived spin coated TiO2 films

Thin films of TiO₂ were prepared using two different sol–gel routes. The two routes employed diethanolamine (DEA) and acetylacetone as stabilizing agents with titanium isopropoxide (Ti(OPrⁱ)₄) in ethanol as the deposition solution. The densification at 500 °C achieved the nanophase TiO₂ films, which were investigated by performing structural, optical and electrochemical studies. Ion storage capacity and transmission measurements showed superior response of the films derived from DEA. Between the films obtained from the two routes, the appearance of the rutile phase at lower temperature for the film synthesized using DEA was predicted on the basis of the thermal analysis of the corresponding xerogel. The nanocrystalline nature of the films was evident from the X-ray diffraction, atomic force microscopy, and scanning electron microscopy. The films deposited from both the stabilizers exhibited electrochromism in 1 M LiClO₄-propylene carbonate electrolyte on cathodic polarization.     

Sol–gel derived nanocrystalline CeO2–TiO2 coatings for electrochromic windows

Mixed CeO₂–TiO₂ coatings synthesized by sol–gel spin coating process using mixed organic–inorganic Ti(OC₃H₇)₄ and CeCl₃·7H₂O precursors with different Ce/Ti mole ratios were investigated by a wide range of characterization techniques. The attempts were directed towards achieving coatings with high transparency in the visible region and good electrochemical properties. Elucidation of the structural and optical features of the films yielded information on the aspects relevant to their usage in transmissive electrochromic devices. The films have been found to exhibit properties for counter electrode in electrochromic smart windows in which they are able to retain their transparency under charge insertion, high enough for practical uses. The high optical modulation and fastest switching for WO₃ film in the device configuration with the Ce/Ti (1:1) film is interpreted in terms of conducive microstructural changes induced by addition of TiO₂ in an amount equivalent to CeO₂.     

Landslide susceptibility zonation study using remote sensing and GIS technology in the Ken-Betwa River Link area,India

The 231 km long Ken-Betwa River Linking canal will transfer 1,020 hm³ of surplus water from the Ken River to the deficit Betwa River basin. The landslide susceptibility zonation map of the river link has been assessed using remote sensing data in GIS. Various thematic maps such as geology, land use/land cover, lineament, drainage, slope, aspect, normalized difference vegetation index and soil type were generated from the Landsat Thematic Mapper 5 satellite data of 2005, the Survey of India topographic sheets, Shuttle Radar Topographic Mission Digital Elevation (SRTM-DEM) data and other existing maps. Numerical rating schemes were used for ranking the thematic layers. The results were supported with the rainfall data, groundwater level data and a petrological study of rock thin sections. In addition to providing valuable information for project decision-makers, the results will assist in slope management and land use planning in the area.     

Nano boron nitride laminated poly(ethyl methacrylate)/poly(vinyl alcohol) composite films imprinted with silver nanoparticles as gas barrier and bacteria resistant packaging materials

Herein, nano boron nitride (BN) laminated poly(ethyl methacrylate) (PEMA)/poly(vinyl alcohol) (PVA) nanocomposite films are fabricated by using a simple in situ polymerization technique with incorporation of silver nanoparticles (Ag NPs). Structural investigations of PEMA/PVA/Ag@BN nanocomposite thin films are carried out by Fourier-transform infrared spectroscopy, dynamic light scattering, X-ray diffraction analysis, ¹H nuclear magnetic resonance, ¹³C nuclear magnetic resonance, and mass spectrometry. The change in morphology of PEMA/PVA matrix due to the reinforcement of BN platelets are identified by electron microscopic studies. The unique tortuous paths are achieved by the dispersion of BN platelets by which gas penetration is restricted with enhancing the barrier properties of the material by 6.5 folds at 5 wt% BN content as compared with neat PEMA/PVA. Acid and alkali resistant along with biodegradability behavior of as-synthesized nanocomposites are studied. From limiting oxygen index (LOI) results, it is found that the prepared materials are fire retardant in nature owing to effective reinforcement of BN layers. Antibacterial activities of PEMA/PVA/Ag@BN nanocomposite are studied by Xanthomonas citri or axonopodis pv. Citri, Escherichia coli, and Xanthomonas oryzae pv. Oryzae because of Ag NPs reinforcement. The substantial improvements in gas barrier, fire retardant, and antibacterial properties enable the materials for packaging application.     

Utilization of chickpea flour in sausages

'English' type fresh skinless sausages were prepared in which some of the meat (mutton, pork or beef) was replaced on a protein to protein basis by chickpea flour. The acceptability of mutton sausages containing chickpea flour was not affected at levels of substitution up to 40%, whereas pork and beef sausages were significantly less acceptable at substitution levels above 30%. In all the sausages incorporation of chickpea flour led to increased cooking losses and softer textures. Incorporation of chickpea flour caused discoloration of the raw sausages which became more prominent during storage at 0°C.