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In this work, synthesis of β-V2O5 nanorods by solvothermal method was adopted at optimum experimental conditions by varying the concentration of NaOH as 0.5M, 1M, 1.5M and 2M. The obtained products were characterization by following techniques, XRD, RAMAN, FTIR, and FESEM. The XRD results reveal the formation of β-V2O5 nanorods and its crystalline nature was confirmed by its lattice parameters. The Raman analysis shows a peak at 485, 770 and 998 cm−1 corresponds to the vibration of O-V-O bonds. Similarly the FITR peaks appeared at the 530 and 786 cm−1 can be attributed to the symmetric stretching of Metal Oxide (V-O). The morphology and its structure of β-V2O5 nanorods can be analysized by the FESEM techniques and its images shows the formation of β-V2O5 nanorods with different dimensions. The role of concentration of NaOH can be studied by comparing the FESEM micrographs. It is clearly evident from FESEM images as the concentration of NaOH increases from 0.5 M to 2M, the shape and size of the change rapidly and the surface effect results in the mesoporous features on the surface of nanorods. Its note worthy as the concentration of NaOH increases results in the flattening of nanorods could be observed due more of interaction of NaOH precursor solution. Published version

In this work the effect of concentration of cetyltrimethylammonium bromide (CTAB) in the synthesis of Nickel doped Manganese oxide (Ni-MnO2) nanoparticles have been carried out by adopting the sol-gel process. The synthesized products were characterized by XRD, Infra- Red (FTIR) and SEM analysis. The XRD confirms the formation of Ni-MnO2 nanoparticles illustrate peak at 31.4° with lattice plane (-231). The IR spectra correspond to the peak at 592 and 846 cm-1 attributed to the characteristics peak for Ni-MnO2 nanoparticles. The SEM images for all three Ni-MnO2 nanoparticles for different concentration of CTAB allows us to assess the formation route of nano tentacles from 10 mM, 30 mM and 50 mM. The configured nano tentacles of Ni-MnO2 nanoparticles presumably leads to more significantly change its properties, particularly in its electrochemical properties show the ways to be suitable candidates for supercapacitor, battery, photo catalytic and fuel cell applications.

High quality Ni-doped CeO2 (CeO2:Ni) thin films were deposited on glass substrates at room temperature by using radio frequency magnetron sputtering. The effect of annealing temperature on structural and optical properties of the CeO2:Ni films was investigated. The structural, optical and vibrational properties of the films were determined using X-ray diffraction (XRD), photoluminescence spectrometer (PL) and Raman spectrometer. It was found that the as-deposited film has a fluorite cubic structure. By increasing annealing temperature from 100°C to 300°C, the crystalline quality of the thin films could be improved. The UV and visible band emissions were observed in the photoluminescence spectra, due to exciton, defect related emissions respectively. The micro-Raman results show the characteristic peak of CeO2 F2g at 465 cm−1 and 2L0 at 1142 cm−1. Defect peaks like D and 0 bands were observed at 641 cm−1 and 548 cm−1 respectively. It is found from the spectra that the peak intensity of the films increased ...

In this work, p-n hetrojunctions based on p-NiO and n-ZnO composite nanostructures were successfully deposited by sol-gel spin coating method. Structural investigations indicate well aligned ZnO nanorods with hexagonal faces having a preferential orientation along the c-axis (002). Scanning electron microscopy (SEM) was used to characterize, the p-n heterostructures formed grain like spherical structure of NiO fully covered the hexagonal rods of ZnO in the NiO/ZnO thin film and elements were confirmed from EDX analysis. PL and micro-Raman spectra of the deposited films showed the variation in luminescence and structural properties due to the formation of heterojuction of NiO.

Cerium oxide (CeO2) thin films were deposited on glass substrates by sputtering at various substrate temperatures. CeO2 films were characterized by X-ray diffraction, FESEM, PL and Raman analyses. X-ray diffraction patterns of films reveal fcc cubic structure with preferential orientation along (2 2 0) crystallographic plane. SEM images show that the particles are uniformly distributed on the film surface. The films were found to be well adheared to the substrates and pin holes are not observed on the surface of the films. PL spectra exhibits a strong near band-gap-edge emission and a broad blue, green luminescence, which can be assigned to the presence of Ce and O vacancies, amorphous phases, deep level impurities and structural defects. The relative intensity between the different peaks of the bands related to defects or impurities was studied as a tool for quality control of the films. Moreover, vibrational measurements through Raman analysis were carried out and the results are discussed.

We systematically investigated the structural, morphological and optical properties of 0.05 mol % Al doped ZnO (Al:ZnO) thin films deposited on glass substrates by sol-gel spin coating method. The influences of Al doping in ZnO thin films are characterized by Powder X-ray diffraction study. ZnO and Al:ZnO thin films have showed hexagonal wurtzite structure without any secondary phase in c-axis (002) orientation. The SEM images also proved the hexagonal rod like morphologies for both films. All the films exhibited transmittance of 70-80% in the visible range up to 800 nm and cut-off wavelength observed at ∼390 nm corresponding to the fundamental absorption of ZnO. The band gap of the ZnO thin films slightly widened with the Al doping. The photoluminescence properties have been studied for Al: ZnO thin films and the results are presented in detail.

Molybdenum oxide (MoO3) nanostructures were grown on different substrates such as glass, indium tin oxide coated glass and fluorine doped glass by thermal evaporation of MoO3 powder at elevated temperature (750°C) using tube furnace without any catalyst and then by subsequent O2/Ar flow rate. The morphology, composition and crystal structure were examined by using SEM, EDAX, Laser Raman and XRD. The films are polycrystalline with well-defined diffraction peaks and it consist of MoO3 with α-orthorhombic structure. The synthesized MoO3 belongs to different morphologies, generally nanobelt and nanohunk structures. The EDAX spectra confirm the films are composed only of Mo and O atoms. The O/Mo ratio is nearly equal to 3 that shows the stoichiometry of MoO3.

4 N, N-dimethylamino N methyl stilbazolium tosylate (DAST) is an excellent organic nonlinear optical material. Single crystal of DAST has been grown by solution growth method using allyl alcohol as a solvent for the first time. Its electro optic properties such as half wave voltage and electro optic figure of merit have been measured for the first time by field induced birefringence method corresponding to the wavelength of 632 nm.

Single crystals of pure and amino acid (L-arginine) doped γ-glycine single crystals have been grown from aqueous solution by employing slow evaporation method. Morphological changes in different crystallographic planes were observed in the L-arginine doped γ-glycine crystals. Incorporation of L-arginine was confirmed qualitatively by FTIR spectroscopy. Powder X-ray diffraction was carried out to confirm γ-glycine and assess the single phase nature of the crystals. The lower cutoff wavelength was decreased by the influence of L-arginine in γ-glycine and this leads to an increase in the band gap. Nonlinear optical study revealed that L-arginine doping increases the SHG efficiency of the glycine crystal.

Single crystals of cadmium manganese thiocyanate (CMTC) have been synthesized successfully and grown by slow evaporation method. The structural perfection of the grown crystals has been analyzed by High resolution X-ray diffraction (HRXRD), which shows the crystalline perfection of the grown crystal is quite good. Optical behavior was assessed by UV-Vis analysis and found that no absorption in the UV visible region and it may be useful for second harmonic applications. The mechanical hardness of the grown crystals was studied and Vicker's microhardness, Stiffness constant was calculated.

Microwave assisted hydrothermal synthesis of ZnO nanostructures with improved surface area by the addition of Citric Acid (CA) as a metal capping agent is reported. Citric acid is added to the mother precursor in three different concentrations for the preparation of ZnO nanostructure. The influence of the citric acid as a capping agent has been studied both in the preparation of ZnO nanopowders and in the ordered array formation on the precoated ZnO seed layer over glass substrates. The addition of this capping agent has shown up clearly in the morphology of the nanostructures. The X‐ray diffraction patterns has shown a diminished crystallinity and a increased full width half maximum (FWHM) in the preferred oriented diffraction peak. The peak broadening is an indication of the reduced crystallite size. This cause of the inhibition in growth is realized to be the effect of capping action of citric acid. The optical property of the ZnO nanostructure was characterized by UV‐vis‐NIR spectroscopy.