Hydrothermal approach for the shape-selective SrSO4:Eu2+ microcrystals and its luminescence properties

ZnS:Cu,Tm nanocrystal with 15nm cubic structures have been synthesized by hydrothermal approach at 200°C. The photoluminescence (PL) properties and the effect of hydrothermal treatment time on the structure, morphology and PL spectra of ZnS:Cu,Tm samples have been studied. The as-obtained samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and FT-IR spectra.The result indicated that the PL emission spectrum of codoped with Cu and Tm sample compares with undoped ZnS and doped with Cu alone samples has a significant changes, while the PL emission peak has red shift and PL emission intensity increased. The samples size and crystallization are increase with extending of the treatment time. However, when the hydrothermal treatment time is too long(>12h), the PL emission intensity of sample instead of decreased. Demonstrated changes in surface state of nanomaterials have a greater impact on its luminescence properties.

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Solvo-Hydrothermal Approach for the Shape-Selective Synthesis of Vanadium Oxide Nanocrystals and Their Characterization

Langmuir ◽

10.1021/la804073a ◽

2009 ◽

Vol 25 (9) ◽

pp. 5322-5332 ◽

Cited By ~ 64

Author(s):

Thanh-Dinh Nguyen ◽

Trong-On Do

Keyword(s):

Vanadium Oxide ◽

Selective Synthesis ◽

Shape Selective ◽

Hydrothermal Approach

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Luminescence from individual dislocations in II-VI and III-V semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088488 ◽

1991 ◽

Vol 49 ◽

pp. 834-835

Author(s):

J W Steeds

Keyword(s):

Group Iv ◽

Luminescence Properties ◽

Carrier Recombination ◽

Transmission Electron ◽

Wide Range ◽

Basic Physics ◽

Semiconducting Compounds ◽

Diamond Group ◽

Non Destructive ◽

Technological Significance

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

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