Defects in quantum dots of IIB–VI semiconductors

Babentsov, V.; Сизов, Ф. Ф.

doi:10.2478/s11772-008-0025-0

Cited by 51 publications

(39 citation statements)

References 65 publications

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“…In order to better understand the origin of their color and luminescence in the paint layer, recent studies [14,15,16,17,18] have focused on luminescence emission lifetimes of luminescent materials. Cd-and Zn-based pigments were characterized [17] both by a rapid picosecond lifetime band gap emission related to pigment composition and by further radiative relaxation decay paths due to trap state levels connected to the presence of intrinsic and extrinsic defects.…”

Section: Introductionmentioning

confidence: 99%

Degradation of Cd-yellow paints: Ab initio study of native defects in {10.0} surface CdS

Giacopetti

Satta

2016

Microchemical Journal

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Section: Introductionmentioning

confidence: 99%

Degradation of Cd-yellow paints: Ab initio study of native defects in {10.0} surface CdS

Giacopetti

Satta

2016

Microchemical Journal

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“…Thus far, a myriad of approaches have been proposed to explicate the observed phenomena, leading to discrepancies among dissimilar models . In light of this, theoretical modelling has been applied to search for new ways of surmounting these issues .…”

Section: Introductionmentioning

confidence: 99%

“…Thus far, a myriad of approaches have been proposed to explicate the observed phenomena, leading to discrepancies among dissimilar models. [13][14][15] In light of this, theoretical modelling has been applied to search for new ways of surmounting these issues. 16,17 A comprehensive investigation into the surface defects of QDs in glasses can give guidance to the design of highly luminescent glasses.…”

Section: Introductionmentioning

confidence: 99%

Understanding the atomic and electronic structures origin of defect luminescence of CdSe quantum dots in glass matrix

Liu

et al. 2019

J Am Ceram Soc

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Well‐defined density functional theory (DFT) calculations are performed as the first exploratory study for the atomic and electronic mechanism of defect mediated morphology and optical properties of CdnSen (n = 3, 10, 13, and 33) quantum dots (QDs) in inorganic amorphous matrix. The intrinsic defects of pristine CdSe QDs, and the interfacial defects between the QDs and surrounding amorphous matrix, were systematically studied. The calculated electronic structure suggested that the pristine CdSe QDs capped by the structural modifiers or non‐bridging oxygen in the amorphous matrix gave rise to the structure reconstruction and paired defect states at the edge of the valence and conduction bands. The orbital analysis elucidated that the redistribution of the majority of HOMO and LUMO electron density was localized over the bonds formed by capping atoms and QDs. These changes in the electronic structures were further demonstrated by CdSe QDs embedded sodium silicate glasses. It turned out that Se atoms at QDs/glass interface were much more active than those found on the surface of organically passivated CdSe QDs. The results serve as a new paradigm in materials research to explore structural origins of defect emission from QDs and a new strategy to develop glasses containing QDs with high photoluminescence quantum efficiency.

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“…Studies of bulk CdS and CdSe crystals have shown at least two near-infrared emission bands associated with traps in addition to the band edge luminescence (E t1 and E t2 ). 9 The exact origin of these states has not been conclusively established but is thought to consist of lattice mismatches, 6 dangling bonds at the surface, traps, and electron acceptor agents. 10 Surface passivation is a well-known technique to eliminate the trap emission.…”

Section: Introductionmentioning

confidence: 99%

Near-Infrared Luminescence of Cadmium Pigments: In Situ Identification and Mapping in Paintings

et al. 2011

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A comprehensive study of the luminescence properties of cadmium pigments was undertaken to determine whether these properties could be used for in situ identification and mapping of the pigments in paintings. Cadmium pigments are semiconductors that show band edge luminescence in the visible range and deep trap luminescence in the red/infrared range. Emission maxima, quantum yields, and excitation spectra from the band edge and deep trap emissions were studied for sixty commercial cadmium pigments that span the color range from yellow to red (reflectance transition 470 to 660 nm). For paints containing cadmium pigments, luminescence from deep traps was more readily observable than that from the band edge, although the yield varied widely from zero to around 4.5%. Optimal excitation for emission is found to be in the visible for both pigments in powder form and mixed with a medium. The maxima of the deep trap emission shift with the band gap energy, providing a potentially useful way to assign pigment type even when used in pigment mixtures. The usefulness of the results of the study on mockups was demonstrated by the mapping of cadmium pigments of different hues with the aid of calibrated luminescence imaging spectroscopy in a painting by Edward Steichen, entitled Study for 'Le Tournesol' (1920). Analysis of the luminescence image cube reveals at least six unique spectral components, associated with emission from white pigments, paint binder, and cadmium red and yellow pigments. The results were compared with those from X-ray fluorescence spectrometry (XRF) and fiber-optic reflection spectroscopy (FORS) and the results obtained on paint samples containing cadmium pigments. These results show that, when present, the emission from traps can be used as an analytical tool to identify cadmium pigments, to distinguish among cadmium sulfide, cadmium zinc sulfide, and cadmium sulfoselenide, and to map cadmium pigments, even in mixtures.

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Defects in quantum dots of IIB–VI semiconductors

Cited by 51 publications

References 65 publications

Degradation of Cd-yellow paints: Ab initio study of native defects in {10.0} surface CdS

Degradation of Cd-yellow paints: Ab initio study of native defects in {10.0} surface CdS

Understanding the atomic and electronic structures origin of defect luminescence of CdSe quantum dots in glass matrix

Near-Infrared Luminescence of Cadmium Pigments: In Situ Identification and Mapping in Paintings

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