Tunable amplification of visible light and two-color green lasers based on different doping concentration Er:YSGG crystal

Visible-light responsible Mn-N-codoped TiO2 nanocrystal photocatalysts were synthesized for the first time by a simple hydrothermal synthesis method. X-ray powder diffraction (XRD) measurement indicated that all of the photocatalysts have an anatase crystallite structure and the increase of the doping concentration had less effect on the structure and particle size. Comparing to N-doped TiO2, a shift of the absorption edge of Mn-N-codoped TiO2 to a lower energy and a stronger absorption in the visible light region were observed. The Mn-N-codoped TiO2 showed a higher photocatalytic reactivity than undoped TiO2 and N-doped TiO2 for the photodegradation of rhodamine B (RhB) under visible light irradiation. The doping concentration had an optimal value, according to the highest photocatalytic activity. This suggested that Mn and N codoping has important effects on the improvement of visible-light responsible photocatalytic activity.

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Preparation of Visible-Light Active Mn-Doped TiO2 Photocatalyst and its Photodegradation of Methylene Blue from Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.531 ◽

2014 ◽

Vol 989-994 ◽

pp. 531-535

Author(s):

Yin Chen ◽

Xiao Jun Ma

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Visible Light ◽

Doping Concentration ◽

Sol Gel ◽

Mn Doping ◽

Enhanced Absorption ◽

Photodegradation Rate ◽

Visible Light Active ◽

Mn Doped

Mn-doped TiO2nanocrystal photocatalysts were prepared by the sol-gel method using MnSO4·H2O as manganese source. The catalysts were characterized by XRD, SEM, EPR, UV-Vis, their photocatalytic activity for methylene blue (MB) degradation was investigated. The results showed that Mn was doped into the crystal lattice of TiO2, and had no influence on TiO2crystal structure; the size of TiO2nanoparticle gradually decreased with Mn doping concentration increasing. The Mn-doped TiO2catalysts have enhanced absorption in the visible light region, and its visible light absorptivity increased with Mn doping concentration increasing. The UV-Vis showed the Mn-doped TiO2showed higher photocatalytic activity than the undoped TiO2for methylene blue degradation under visible light irradiation. It is also found that the MB photodegradation rate of Mn-doped TiO2improved by 46% than that of the undoped TiO2.

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Photon yields in 3HF scintillating fibers as a function of doping concentration with visible light photon counters

Proceedings of 1994 IEEE Nuclear Science Symposium - NSS'94 ◽

10.1109/nssmic.1994.474549 ◽

2002 ◽

Author(s):

M. Atac ◽

D. Chrisman ◽

J. Park ◽

M. Mishina

Keyword(s):

Visible Light ◽

Doping Concentration ◽

Scintillating Fibers

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A facile synthesis of Co-doped g-C3N4 catalyst to activate peroxymonosulfate for organic pollutants degradation under visible light

E3S Web of Conferences ◽

10.1051/e3sconf/202126104001 ◽

2021 ◽

Vol 261 ◽

pp. 04001

Author(s):

Fangli Chi ◽

Shengshu Ai ◽

Fan Wang ◽

Xiaona Ji ◽

Dejun Bian

Keyword(s):

Visible Light ◽

Doping Concentration ◽

Visible Light Photocatalysis ◽

Cobalt Doping ◽

X Ray Diffraction ◽

Facile Synthesis ◽

X Ray ◽

Ft Ir ◽

Calcination Method ◽

Co Doped

Co-g-C3N4 catalyst was prepared by a simple calcination method using melamine and Co(NO3)3·6H2O as precursors. X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR) were used to characterize the prepared samples. The results indicated the Co species are successfully coordinated with g-C3N4. Degradation experiments showed that Rhodamine B can be degraded effectively at a very low cobalt doping concentration (0.2 wt %). The enhanced catalytic activity may result from the synergistic effect of visible light photocatalysis and sulfate radical based Co-g-C3N4/PMS system.

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Variations in the structural, electronic and optical properties of N-doped TiO2 with increasing N doping concentration

Modern Physics Letters B ◽

10.1142/s0217984915500220 ◽

2015 ◽

Vol 29 (08) ◽

pp. 1550022 ◽

Cited By ~ 14

Author(s):

Matiullah Khan ◽

Sahar Ramin Gul ◽

Jing Li ◽

Wenbin Cao

Keyword(s):

Visible Light ◽

Band Gap ◽

Density Functional ◽

Doping Concentration ◽

Density Functional Theory Calculations ◽

Theoretical Background ◽

Functional Theory ◽

Visible Light Absorption ◽

Light Region ◽

N Doping

Based on density functional theory, calculations were performed for geometrically optimized N -doped TiO 2 models. The effect of N dopant and its increasing doping concentration on the band structure are elucidated. N doping narrowed the band gap of TiO 2 and introduced isolated N 2p states within the band gap. The location of N 2p states within the band gap can be optimized by N doping concentration. All N -doped TiO 2 models shifted the absorption edge of TiO 2 toward visible light region and increasing N doping concentration improved the visible light absorption. N -doped TiO 2 model having reduced band gap without any isolated states will improve the photocatalytic response. Our results provide strong theoretical background for existing experiments.

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Studies of metaphase chromosomes in the scanning transmission x-ray microscope: Image fidelity, radiation damage and specimen preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129826 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1038-1039

Author(s):

Shawn Williams ◽

Xiaodong Zhang ◽

Susan Lamm ◽

Jack Van’t Hof

Keyword(s):

Visible Light ◽

Radiation Damage ◽

Cross Section ◽

Imaging Techniques ◽

Dose Range ◽

Specimen Preparation ◽

X Rays ◽

Metaphase Chromosomes ◽

X Ray ◽

Scanning Transmission

The Scanning Transmission X-ray Microscope (STXM) is well suited for investigating metaphase chromosome structure. The absorption cross-section of soft x-rays having energies between the carbon and oxygen K edges (284 - 531 eV) is 6 - 9.5 times greater for organic specimens than for water, which permits one to examine unstained, wet biological specimens with resolution superior to that attainable using visible light. The attenuation length of the x-rays is suitable for imaging micron thick specimens without sectioning. This large difference in cross-section yields good specimen contrast, so that fewer soft x-rays than electrons are required to image wet biological specimens at a given resolution. But most imaging techniques delivering better resolution than visible light produce radiation damage. Soft x-rays are known to be very effective in damaging biological specimens. The STXM is constructed to minimize specimen dose, but it is important to measure the actual damage induced as a function of dose in order to determine the dose range within which radiation damage does not compromise image quality.

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Scanning luminescence x-ray microscopy: Progress toward selective staining using microspheres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168104 ◽

1994 ◽

Vol 52 ◽

pp. 74-75

Author(s):

C. Jacobsen ◽

J. Fu ◽

S. Mayer ◽

Y. Wang ◽

S. Williams

Keyword(s):

Visible Light ◽

Active Sites ◽

Light Emission ◽

Chinese Hamster ◽

Polystyrene Spheres ◽

Good Resistance ◽

X Ray ◽

Selective Staining ◽

Visible Light Emission ◽

Specific Labelling

In scanning luminescence x-ray microscopy (SLXM), a high resolution x-ray probe is used to excite visible light emission (see Figs. 1 and 2). The technique has been developed with a goal of localizing dye-tagged biochemically active sites and structures at 50 nm resolution in thick, hydrated biological specimens. Following our initial efforts, Moronne et al. have begun to develop probes based on biotinylated terbium; we report here our progress towards using microspheres for tagging.Our initial experiments with microspheres were based on commercially-available carboxyl latex spheres which emitted ~ 5 visible light photons per x-ray absorbed, and which showed good resistance to bleaching under x-ray irradiation. Other work (such as that by Guo et al.) has shown that such spheres can be used for a variety of specific labelling applications. Our first efforts have been aimed at labelling ƒ actin in Chinese hamster ovarian (CHO) cells. By using a detergent/fixative protocol to load spheres into cells with permeabilized membranes and preserved morphology, we have succeeded in using commercial dye-loaded, spreptavidin-coated 0.03μm polystyrene spheres linked to biotin phalloidon to label f actin (see Fig. 3).

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Photocatalyst-free decarboxylative aminoalkylation of imidazo[1,2-a]pyridines with N-aryl glycines enabled by visible light

Organic Chemistry Frontiers ◽

10.1039/c9qo00935c ◽

2019 ◽

Vol 6 (21) ◽

pp. 3693-3697 ◽

Cited By ~ 11

Author(s):

Jiu-Jian Ji ◽

Zhi-Qiang Zhu ◽

Li-Jin Xiao ◽

Dong Guo ◽

Xiao Zhu ◽

...

Keyword(s):

Visible Light

A novel, green and efficient visible-light-promoted decarboxylative aminoalkylation reaction of imidazo[1,2-a]pyridines with N-aryl glycines has been described.

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