Anomalous photo-induced spectral changes in CdSe/ZnS quantum dots

Shcherbatyuk, Georgiy; Inman, Richard; Ghosh, Sayantani

doi:10.1063/1.3630977

Cited by 20 publications

(31 citation statements)

References 25 publications

(29 reference statements)

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“…20 Such elevated temperatures can lead to photo-oxidation of the printed QDs, which reduces the effective size of the QDs and thus causes a spectral blue-shift. 29,30 The rapid photo-oxidation process can limit the introduction of multiple non-radiative states on the QD surfaces, minimizing the influence on the quantum yield and brightness of the QDs. 29 The bubble printing at the lowest stage speed (1 μm s −1 ) has the maximum laser-heating effect and the photo-oxidation is sufficient to have the QDs emit blue light irrespective of the line space.…”

Section: Resultsmentioning

confidence: 99%

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Patterning and fluorescence tuning of quantum dots with haptic-interfaced bubble printing

et al. 2017

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Semiconductor quantum dots (QDs) are attractive for a wide range of applications such as displays, light-emitting devices, and sensors due to their properties such as tunable fluorescence wavelength, high brightness, and narrow bandwidth. Most of the applications require precise patterning of QDs with targeted properties on solid-state substrates. Herein, we have developed a haptic-interfaced bubble printing (HIBP) technique to enable high-resolution (510 nm) high-throughput (>104 μm s−1) patterning of QDs with strong emission tunability and to significantly enhance the accessibility of the technique via a smartphone device. The scalability and versatility of the HIBP are demonstrated in our arbitrary patterning of QDs on plasmonic substrates. A detailed study of plasmonic and photothermal interactions is performed via programmed stage movements to realize tunability of the emission wavelength and lifetime. Finally, the influence of the hand movement on the properties of the printed QDs in terms of emission wavelength tuning from yellow to blue is established. This work provides a single-step macroscale platform to manipulate nanoscale properties at high resolution and high throughput.

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Section: Resultsmentioning

confidence: 99%

“…In addition, the spectrum broadens at the slower hand movement due to the continued photo-oxidation. 30 …”

Section: Resultsmentioning

confidence: 99%

Patterning and fluorescence tuning of quantum dots with haptic-interfaced bubble printing

et al. 2017

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“…Photo-oxidation of CdSe/ZnS QDs is also linked to the emergence of an additional emission peak that is blueshifted in the photoemission spectrum. 20 Previous research has also shown that substrates can have significant impacts on PFE. This was done by studying photoejection of electrons in QDs into the deep trap states of their substrates.…”

Section: Introductionmentioning

confidence: 98%

“…Characteristic signatures of such oxidation are a blueshift and broadening of the fluorescence spectra. 12,15,19,20 These signatures, called photobleaching, are reportedly caused by reduction of the core sizes of QDs during oxidation as well as degradation of their shells. Photo-oxidation of CdSe/ZnS QDs is also linked to the emergence of an additional emission peak that is blueshifted in the photoemission spectrum.…”

Section: Introductionmentioning

confidence: 99%

Chromium-oxide enhancement of photo-oxidation of CdSe/ZnS quantum dot solids

Sadeghi

Nejat

Weimer

et al. 2012

Journal of Applied Physics

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Published by the American Institute of Physics. Related ArticlesEffect of dimensionality and morphology on polarized photoluminescence in quantum dot-chain structures J. Appl. Phys. 112, 084314 (2012) Quasiresonant excitation of InP/InGaP quantum dots using second harmonic generated in a photonic crystal cavity Appl. Phys. Lett. 101, 161116 (2012) Size-dependent radiative decay processes in graphene quantum dots Appl. Phys. Lett. 101, 163103 (2012) Optical absorbance of doped Si quantum dots calculated by time-dependent density functional theory with partial electronic self-interaction corrections J. Chem. Phys. 137, 144301 (2012) Analysis of the modified optical properties and band structure of GaAs1−xSbx-capped InAs/GaAs quantum dotsIn this paper, we report the results of depositing CdSe/ZnS quantum dots (QDs) on Cr coated substrates. Compared to such QDs on glass surfaces, the emission peak blueshifts and broadens much more rapidly. The acceleration of the process is presented by showing the relative intensity, position, and full-width as a function of time for various laser intensities, and the effects on photoinduced fluorescence enhancement and photo-oxidiation are discussed. We also consider the thickness of the Cr layer and photo-induced heating, showing this factor should instead lead to a redshift of the peak. Oxidation of colloidal QDs is known to cause blueshifts and broadening of emission peaks (photobleaching). We attribute the faster photobleaching of QDs on Cr films to enhancement in the oxidation of the ZnS shell by catalytic or direct chemical reactions with chromium oxides. As a working hypothesis, this leads to additional paths for breakdown of the otherwise protective nature of the shell. V C 2012 American Institute of Physics. [http://dx.

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“…Finally, it is worth stating that fluorescence imaging, however accomplished, has some intrinsic limitations. These include moderate sensitivity and dynamic range, 18 problems with autofluorescence background, variable reagent and specimen stability, varying quantum yields, 19 and potential channel cross-talk. 20 Nevertheless, IHC and IF imaging techniques provide unique biological information that in many cases cannot be attained by other methods.…”

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confidence: 99%

Immunohistochemistry and mass spectrometry for highly multiplexed cellular molecular imaging

Levenson

Borowsky

Angelo

2015

Laboratory Investigation

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The role of immunohistochemistry (IHC) in the management of cancer has expanded to provide improved diagnostic classification, as well as guidance on disease prognosis, therapy, and relapse. These new tasks require evaluation of an increasing number of protein targets; however, conventional multiplexing, usually achieved using serial tissue sections stained for a single analyte per slide, can exhaust small biopsy specimens, complicate slide-to-slide protein expression correlation, and leave insufficient material for additional molecular assays. A new approach, mass spectrometry immunohistochemistry (MSIHC), compatible with high levels of target multiplexing and suitable for use on formalin-fixed, paraffin-embedded samples can circumvent many of these issues. The strategy employs antibodies that are labeled with elemental mass tags, such as isotopically pure lanthanides not typically found in biological specimens, rather than with typical fluorophores or chromogens. The metal-labeled antibodies are then detected in tissue using lasers or ion beams to liberate the tags for subsequent mass spectrometry detection. Within a given multiplexed IHC panel, the metal labels are selected so that their respective masses do not overlap. More than 30 antibodies have been imaged simultaneously, and up to 100 antibodies could potentially be detected at once if the full available mass spectrum is deployed. MSIHC has a number of advantages over conventional IHC techniques. Background due to autofluorescence is absent and the dynamic range is 10 5 , exceeding immunofluorescence and chromogenic IHC by 100-fold and 1000-fold, respectively. Detection of labeled primary antibodies improves assay linearity over both chromogenic and fluorescent IHC. Multiplexed mass-tagged antibodies incubated simultaneously with tissue do not appear to cross-interfere, and because the mass tags do not degrade, samples are stable indefinitely. The imaging resolution of multiplexed ion-beam imaging can be better than light microscopy. With appropriate instrumentation, MSIHC has the potential to transform research and clinical pathology practice.

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Anomalous photo-induced spectral changes in CdSe/ZnS quantum dots

Cited by 20 publications

References 25 publications

Patterning and fluorescence tuning of quantum dots with haptic-interfaced bubble printing

Patterning and fluorescence tuning of quantum dots with haptic-interfaced bubble printing

Chromium-oxide enhancement of photo-oxidation of CdSe/ZnS quantum dot solids

Immunohistochemistry and mass spectrometry for highly multiplexed cellular molecular imaging

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