X-ray activated ultra-violet afterglow in LiLuF4: Ce microcrystals

ABSTRACTSurface lattice displacements of titanium dioxide (TiO2: rutile) during ultra-violet (UV) light irradiation have been investigated using a total reflection x-ray diffraction, which provides a high signal to noise ratio (S/N) and superior in-plane surface diffraction. Under the environments in vapors of H2O, CH3OH, C2H5OH and C3H6OH, the photo-catalytic activities of TiO2 (110), (100) and (001) surfaces subject to UV irradiation have been measured. It is found that the diffraction peaks and their full width half maxima (FWHMs) show some peculiarities with respect to the photo-catalytic activities in both surface lattices and adsorbed molecules in vapors. Furthermore, Kelvin force microscopy (KFM) has showed that there exists a very high surface potential, probably due to surface atom displacements induced by UV irradiation. With regard to the origin of the photo-catalytic activities, the induced surface potentials are discussed.

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Screen Printing Strategy for Investigation of Spectrophotometric Properties of Modified Thick Films of Zirconium Oxide (ZrO2): Tin Oxide (SnO2) Composites

Oriental Journal Of Chemistry ◽

10.13005/ojc/370515 ◽

2021 ◽

Vol 37 (5) ◽

pp. 1117-1124

Author(s):

R. M. Nikam ◽

A. P. Patil ◽

K. H. Kapadnis ◽

A. D. Ahirrao ◽

R.Y. Borse

Keyword(s):

Tin Oxide ◽

Integrated Circuit ◽

Zirconium Oxide ◽

Screen Printing ◽

Thick Films ◽

Ultra Violet ◽

Spectrophotometric Study ◽

X Ray Diffraction ◽

X Ray ◽

Hybrid Integrated Circuit

There are numerous methods has been investigated and developed for the preparation of thin and thick films. Thick film technology is utilized for the production of electronic devices like surface mount devices, in the preparation of hybrid integrated circuit, in the formulation of heating elements, in the construction of integrated passive devices and sensors. Pure tin oxide (SnO2) and composite 1%, 3%, 5%, 7% and 9 % zirconium oxide (ZrO2) thick films of dimensions 2 cm×1 cm incorporated into pure tin oxide (SnO2) were prepared with standard screen printing method. All samples were fabricated on glass support. The thick films were subjected to drying and firing at 5000C at 5 hours in muffle furnace. Thick films of tin oxide (SnO2) and composite 1%, 3%, 5%, 7% and 9 % zirconium oxide (ZrO2) incorporated into pure tin oxide (SnO2) were checked for Scanning Electron Microscopy (S.E.M), Energy Dispersive X-ray Spectroscopy (E.D.A.X), X-ray diffraction (X.R.D), Fourier Transform infra-Red (F.T.I.R) and Ultra-Violet-Visible spectroscopy (U.V) for surface morphology, elemental analysis, crystalline phases of films, vibrational and spectrophotometric study respectively. In this research paper the spectrophotometric parameters such as absorbance and absorption coefficient with pure and compositional thick films were a part of investigation and surveillance.

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Effects of nitrogen substitution in amorphous carbon films on electronic structure and surface reactivity studied with x-ray and ultra-violet photoelectron spectroscopies

Journal of Applied Physics ◽

10.1063/1.4976810 ◽

2017 ◽

Vol 121 (9) ◽

pp. 095302 ◽

Cited By ~ 3

Author(s):

Yuma Murata ◽

Rempei Nakayama ◽

Fumihiko Ichihara ◽

Hiroshi Ono ◽

Cheow-Keong Choo ◽

...

Keyword(s):

Electronic Structure ◽

Amorphous Carbon ◽

Ultra Violet ◽

Carbon Films ◽

Surface Reactivity ◽

Amorphous Carbon Films ◽

X Ray ◽

Nitrogen Substitution

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Hierarchical Nanostructured ZnO-CuO Nanocomposite and its Photocatalytic Activity

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.35.21 ◽

2015 ◽

Vol 35 ◽

pp. 21-26 ◽

Cited By ~ 16

Author(s):

Susmita Das ◽

Vimal Chandra Srivastava

Keyword(s):

Photocatalytic Activity ◽

Pure Copper ◽

Ultra Violet ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Ultra Violet Radiation ◽

One Step ◽

Uv Visible

Metal oxide nanocomposite (ZnO-CuO) was successfully synthesized by one step homogeneous coprecipitation method and further characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), X-ray diffraction analysis (XRD) and UV-visible diffuse reflectance spectra. XRD analysis exhibited presence of pure copper oxide and zinc oxide within the nanocomposite. SEM analysis indicated that the ZnO-CuO nanocomposite was consisted of flower shaped ZnO along with leaf shaped CuO. Photocatalytic activity of nanocomposite was evaluated in terms of degradation of methylene blue (MB) dye solution under ultra-violet radiation. Results showed that the photocatalytic efficiency of ZnO-CuO nanocomposite was higher than its individual pure oxides (ZnO or CuO).

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Beating absorption in solid-state high harmonics

Communications Physics ◽

10.1038/s42005-020-00472-5 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Hanzhe Liu ◽

Giulio Vampa ◽

Jingyuan Linda Zhang ◽

Yu Shi ◽

Siddharth Buddhiraju ◽

...

Keyword(s):

Vacuum Ultraviolet ◽

Crystalline Silicon ◽

High Harmonic ◽

Ultra Violet ◽

Fold Increase ◽

High Energy ◽

High Order ◽

Limiting Factor ◽

X Ray ◽

On Chip

Abstract Since the new millennium coherent extreme ultra-violet and soft x-ray radiation has revolutionized the understanding of dynamical physical, chemical and biological systems at the electron’s natural timescale. Unfortunately, coherent laser-based upconversion of infrared photons to vacuum-ultraviolet and soft x-ray high-order harmonics in gaseous, liquid and solid targets is notoriously inefficient. In dense nonlinear media, the limiting factor is strong re-absorption of the generated high-energy photons. Here we overcome this limitation by generating high-order harmonics from a periodic array of thin one-dimensional crystalline silicon ridge waveguides. Adding vacuum gaps between the ridges avoids the high absorption loss of the bulk and results in a ~ 100-fold increase of the extraction depth. As the grating period is varied, each high harmonic shows a different and marked modulation, indicating their waveguiding in the vacuum slots with reduced absorption. Looking ahead, our results enable bright on-chip coherent short-wavelength sources and may extend the usable spectral range of traditional nonlinear crystals to their absorption windows. Potential applications include on-chip chemically-sensitive spectro-nanoscopy.

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High-Performance Flexible Ultraviolet Photodetectors with Ni/Cu-Codoped ZnO Nanorods Grown on PET Substrates

Nanomaterials ◽

10.3390/nano9081067 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1067 ◽

Cited By ~ 8

Author(s):

Hafiz Muhammad Salman Ajmal ◽

Fasihullah Khan ◽

Noor Ul Huda ◽

Sunjung Lee ◽

Kiyun Nam ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

High Performance ◽

Electronic Device ◽

Deep Level ◽

Zno Nanorods ◽

Ultra Violet ◽

Device Fabrication ◽

Electrode Structure ◽

Large Area ◽

X Ray

As a developing technology for flexible electronic device fabrication, ultra-violet (UV) photodetectors (PDs) based on a ZnO nanostructure are an effective approach for large-area integration of sensors on nonconventional substrates, such as plastic or paper. However, photoconductive ZnO nanorods grown on flexible substrates have slow responses or recovery as well as low spectral responsivity R because of the native defects and inferior crystallinity of hydrothermally grown ZnO nanorods at low temperatures. In this study, ZnO nanorod crystallites are doped with Cu or Ni/Cu when grown on polyethylene terephthalate (PET) substrates in an attempt to improve the performance of flexible PDs. The doping with Ni/Cu or Cu not only improves the crystalline quality but also significantly suppresses the density of deep-level emission defects in as-grown ZnO nanorods, as demonstrated by X-ray diffraction and photoluminescence. Furthermore, the X-ray photoelectron spectroscopy analysis shows that doping with the transition metals significantly increases the oxygen bonding with metal ions with enhanced O/Zn stoichiometry in as-grown nanorods. The fabricated flexible PD devices based on an interdigitated electrode structure demonstrates a very high R of ~123 A/W, a high on-off current ratio of ~130, and a significant improvement in transient response speed exhibiting rise and fall time of ~8 and ~3 s, respectively, by using the ZnO nanorods codoped by Ni/Cu.

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Synthesis of Zn1−xCdxO Nanoparticles by Co-Precipitation: Structural, Optical and Photodetection Analysis

International Journal of Nanoscience ◽

10.1142/s0219581x17600158 ◽

2017 ◽

Vol 17 (01n02) ◽

pp. 1760015 ◽

Cited By ~ 2

Author(s):

Anju Anna Jacob ◽

L. Balakrishnan ◽

S. R. Meher ◽

K. Shambavi ◽

Z. C. Alex

Keyword(s):

Zinc Oxide ◽

Energy Dispersive Spectrometer ◽

Ultra Violet ◽

Wide Bandgap ◽

Precipitation Method ◽

Cutoff Wavelength ◽

X Ray ◽

Wide Bandgap Semiconductor ◽

Co Precipitation ◽

Scanning Electron

Zinc oxide (ZnO) is a wide bandgap semiconductor with excellent photoresponse in ultra-violet (UV) regime. Tuning the bandgap of ZnO by alloying with cadmium can shift its absorption cutoff wavelength from UV to visible (Vis) region. Our work aims at synthesis of Zn[Formula: see text]CdxO nanoparticles by co-precipitation method for the fabrication of photodetector. The properties of nanoparticles were analyzed using X-ray diffractometer, UV–Vis spectrometer, scanning electron microscope and energy dispersive spectrometer. The incorporation of cadmium without altering the wurtzite structure resulted in the red shift in the absorption edge of ZnO. Further, the photoresponse characteristics of Zn[Formula: see text]CdxO nanopowders were investigated by fabricating photodetectors. It has been found that with Cd alloying the photosensitivity was increased in the UVA-violet as well in the blue region.

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