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The effects of CeO2 and CdS on the optical properties of ZnO have been investigated. ZnO-CeO2 and ZnO-CdS, ZnO-CeO2 and ZnO-CdS-CeO2 nanocomposites were prepared by solid state method and sintered at 600° C. XRD, FTIR, UV absorption, and fluorescence spectroscopy were used to investigate the optical and structural properties of the prepared composite material. According to the XRD pattern, the average particle size of ZnO-CdS is 54.94 nm, ZnO-CeO2 is 61.95 nm, and ZnO-CdS-CeO2 is 43.17 nm as calculated by Scherer's formula. The FTIR spectra revealed the presence of different functional groups in the composite material. The optical band gap of ZnO-CdS is 2.75eV, that of ZnO-CeO2 is 4.18eV, and that of ZnO-CdS-CeO2 is 3.41eV. To analyse the luminescence spectra, the prepared composites are excited at 370nm. [ABSTRACT FROM AUTHOR]

Pure SrTiO3 (STO) was prepared by wet chemical route sintered at 1100oC. The Prepared sample was characterized by FT-IR, UV absorption, XRD and Photoluminescence.FT–IR a spectrum of STO had broad absorption peaks around 1000 cm−1 was due to crystal lattice vibrations. Absorption peaks at 922, 972 and 538 cm−1 were due to stretching vibration of Sr-O and Ti-O bond, respectively. XRD study reveals that STO had a typical perovskite of cubic symmetry indexed by standard JCPDS PDF No. 89-4934. The average crystallite size was calculated by using Scherer's formula and found to be 87.20 nm.UV absoption spectra showed that broad abroption peak in the UV region was around 250–320 nm, as expected. Emission spectra had broad emission in yellowish-green visible region excited by 259nm. It was concluding that prepared nanophosphor is highly recommended for display applications. [ABSTRACT FROM AUTHOR]

In the agriculture field, the production yield is often less than the farmer's expected value because a few parts of the crops are damaged by pests and insects. Chemical pesticides have wide applications in the agriculture field. Through the agricultural run-off, these pesticides contaminate the water sources. So, there is a need for highly efficient La-doped ZnO photocatalytic material for pesticide degradation. Photocatalytic material was synthesized via a hydrothermal route. Zn (NO)3.6H2O and La (NO3)3.6HM2O was used as zinc and lanthanum precursor in ethanol. Surface Morphology and dopant composition were analyzed by SEM-EDX images which confirmed the hybrid of the metal doping process. [ABSTRACT FROM AUTHOR]

Pure ZnO, pure CeO2 and, composite of ZnO/CeO2 was prepared by solid state method and sintered a 600° C. The prepared sample was characterized by using XRD, UV absorption and Fluorescence spectrometer. Average particle size of ZnO/CeO2 composite was 61.95 nm where pure ZnO had average particle size of 41.23 nm may be due to the large ionic radius of Ce+3 as compared to Zn+2. Blue shift in band gap had been observed for ZnO/CeO2 composite as compared to pure ZnO. To study the luminescence spectra, the prepared material was excited by 370 nm. From the data it was observed that the material shows good optical emission in violet and far red region. Therefore, it has been concluded that prepared sample can further be explore for grow light. [ABSTRACT FROM AUTHOR]

Chlorpyrifos insecticide is one of the most extensively used organophosphorus pesticides due to its low cost and excellent performance in controlling pests in agriculture fields and gardens. The presence of pesticides in the aquatic environment produces a slew of issues for both humans and ecosystems. The purpose of this research is to assess the photocatalytic detoxification of chlorpyrifos in wastewater utilizing g-C₃N₄/GO nanoparticles. The g-C₃N₄/GO nanoparticles were successfully synthesized by using calcinations and hydrothermal methods. Additionally, the photocatalytic detoxification of chlorpyrifos was examined by optimizing several parameters such as catalyst type, irradiation period, catalyst concentrations, and pH. The photocatalytic efficiency of g-C₃N₄/GO nanoparticles was determined by using a UV–visible spectrophotometer. According to the findings of this study, the photo detoxification effectiveness of chlorpyrifos pesticides rises with increasing illumination time, and detoxification of chlorpyrifos by using a photo-catalyst was strongly influenced by the operational parameters. [ABSTRACT FROM AUTHOR]

Complex vanadium oxide is an excellent multifunctional material. Various forms of vanadium oxide was synthesized out of them orthorhombic V2O5 form is more stable. In this manuscript hydrothermal process and mechanochemical process is adopted of the synthesised of Vanadium oxide in different morphological phases. The samples are characteristics by XRD methods using a hydrothermal technique, the V2O5 precursor was successfully synthesised by mixing NH4VO3 and C2H2O4 in a 1:1 molar concentration ratio and conducted the reaction at 150 °C for 7 hours. The orthorhombic phase V2O5 formation is confirmed by the X-ray diffraction. The position of the peak and the quality of the phase formation is tabulated in the paper. Hydrothermal method displays high crystalline belt like formation while mechanochemical method shows formation of nano-particle with deteriorated degree of crystalline confirmed by SEM. The synthesis of high crystalline vanadium oxide orthorhombic phase in different morphologies opens up a way to utilize such materials towards the energy storage and sensing applications. [ABSTRACT FROM AUTHOR]

The color tunability property of nano-sized semiconducting materials for broad range visible light emission (400-700 nm) depends upon the excitation wavelength, particle size, and sintering temperature. Defect states are the most common cause of visual emission from semiconducting materials. A lot of work had been reported on visible emission due to defect centers. An attempt has been made to study the visible emission from pure ZnO, pure CdS and ZnO/CdS nano composite sintered at 600oC. Powder XRD spectra of the samples were indexed using JCPDC file No. 36-1451 confirming the hexagonal wurtzite phase. XRD pattern confirmed that CdS in ZnO did not change the hexagonal phase of ZnO. The average particle size of ZnO/CdS composite was 56.8 nm where pure ZnO had average particle size of 39 nm. The emission properties of pure ZnO, pure CdS and ZnO/CdS composite have multicolor emission due to defect center. With the introduction of CdS in ZnO, the emission properties of the ZnO/CdS nano composite were enhanced. As a result, ZnO/CdS nano composites have greater potential for optoelectronic applications than pure ZnO and CdS. [ABSTRACT FROM AUTHOR]

Magnesium aluminate (MgAl2O4) and Zinc aluminate (ZnAl2O4) powder were prepared using the sol-gel method. The prepared sample was dried at 1500C and sintered at 7000C. The phase formation of both the samples was confirmed through X-Ray Diffraction (XRD). Fourier Transfer Infrared Spectroscopy (FTIR) showed the successful formation of metal-oxygen bonds of both the materials. The UV Visible spectra of MgAl2O4 and ZnAl2O4 at 7000C showed maximum absorption in UV region. The bandgap of the prepared material was analyzed from UV-Vis spectroscopy which concluded that the material is a wide bandgap semiconductor. The luminescence properties of the material were analyzed from fluorescence spectroscopy (FL) and have emission in the visible region. It is concluded that the material is suitable for display devices. [ABSTRACT FROM AUTHOR]