skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Temperature-sensitive photoluminescent CdSe-ZnS polymer composite film for lock-in photothermal characterization

Abstract

The temperature dependence of the fluorescence spectrum of CdSe−ZnS core–shell quantum dots embedded in a polystyrene matrix is characterized between 30 °C and 60 °C. The spectrally integrated photoluminescence intensity is found to linearly decrease with −1.3%/ °C. This feature is exploited in a dual coating-substrate-configuration, consisting of a layer of this nanocomposite material, acting as a temperature sensor with optical readout, on top of an optically absorbing and opaque layer, acting as a photothermal excitation source, and covering a substrate material or structure of interest. From the frequency dependence of the optically detected photothermal signal in the frequency range between 5 Hz and 150 Hz, different thermal parameters of the constituent layers are determined. The fitted values of thermal properties of the different layers, determined in different scenarios in terms of the used a priori information about the layers, are found to be internally consistent, and consistent with literature values.

Authors:
; ; ;  [1];  [2];  [3]
  1. Department of Physics and Astronomy, Laboratory for Soft Matter and Biophysics, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee (Belgium)
  2. Department of Chemistry, Molecular Imaging and Photonics, KU Leuven, Celestijnenlaan 200 F- box 2404, 3001 Heverlee (Belgium)
  3. Department of Mechanics of Materials and Constructions, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels (Belgium)
Publication Date:
OSTI Identifier:
22596791
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 22; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CADMIUM SELENIDES; EXCITATION; FILMS; FLUORESCENCE; FLUORESCENCE SPECTROSCOPY; FREQUENCY DEPENDENCE; FREQUENCY RANGE; LAYERS; NANOCOMPOSITES; PHOTOLUMINESCENCE; POLYSTYRENE; QUANTUM DOTS; READOUT SYSTEMS; SENSORS; SIGNALS; SUBSTRATES; TEMPERATURE DEPENDENCE; THERMODYNAMIC PROPERTIES; ZINC SULFIDES

Citation Formats

Liu, Liwang, E-mail: liwang.liu@hotmail.com, Meng, Lei, Wang, Ling, Glorieux, Christ, Zhong, Kuo, and Van Hemelrijck, Danny. Temperature-sensitive photoluminescent CdSe-ZnS polymer composite film for lock-in photothermal characterization. United States: N. p., 2016. Web. doi:10.1063/1.4953591.
Liu, Liwang, E-mail: liwang.liu@hotmail.com, Meng, Lei, Wang, Ling, Glorieux, Christ, Zhong, Kuo, & Van Hemelrijck, Danny. Temperature-sensitive photoluminescent CdSe-ZnS polymer composite film for lock-in photothermal characterization. United States. doi:10.1063/1.4953591.
Liu, Liwang, E-mail: liwang.liu@hotmail.com, Meng, Lei, Wang, Ling, Glorieux, Christ, Zhong, Kuo, and Van Hemelrijck, Danny. 2016. "Temperature-sensitive photoluminescent CdSe-ZnS polymer composite film for lock-in photothermal characterization". United States. doi:10.1063/1.4953591.
@article{osti_22596791,
title = {Temperature-sensitive photoluminescent CdSe-ZnS polymer composite film for lock-in photothermal characterization},
author = {Liu, Liwang, E-mail: liwang.liu@hotmail.com and Meng, Lei and Wang, Ling and Glorieux, Christ and Zhong, Kuo and Van Hemelrijck, Danny},
abstractNote = {The temperature dependence of the fluorescence spectrum of CdSe−ZnS core–shell quantum dots embedded in a polystyrene matrix is characterized between 30 °C and 60 °C. The spectrally integrated photoluminescence intensity is found to linearly decrease with −1.3%/ °C. This feature is exploited in a dual coating-substrate-configuration, consisting of a layer of this nanocomposite material, acting as a temperature sensor with optical readout, on top of an optically absorbing and opaque layer, acting as a photothermal excitation source, and covering a substrate material or structure of interest. From the frequency dependence of the optically detected photothermal signal in the frequency range between 5 Hz and 150 Hz, different thermal parameters of the constituent layers are determined. The fitted values of thermal properties of the different layers, determined in different scenarios in terms of the used a priori information about the layers, are found to be internally consistent, and consistent with literature values.},
doi = {10.1063/1.4953591},
journal = {Journal of Applied Physics},
number = 22,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
  • Photoluminescence (PL) and Electroluminescence (EL) measurements have been used to characterize the excited state properties of Cdchalcogenide single crystal electrodes in photoelectrochemical solar cells (PEC's). Polycrystalline thin film electrodes of these materials, which are promising candidates for the efficient photoelectrochemical solar energy conversion, have been studied only very recently using PL. As EL originates more close to the surface of the electrodes, it is considered a probe of recombination more sensitive than PL to the surface conditions of the sample. The authors report the first EL measurements with electrodeposited thin film CdSe electrodes and tahe enhancement of EL efficiency uponmore » photoetching (4). CdSe thin film electrodes were prepared onto Ti substrates by electroplating according to literature procedures. The electrodes were annealed at 600/sup 0/C in N/sub 2/ and photoetched in a (0.3:9.7:90) HNO/sub 3/:HC1:H/sub 2/O solution under white light illumination shortening the photoelectrode to a carbon counterelectrode. Room temperature luminescence spectra were taken with a 0.5m SPEX monochromator and a cooled S-1 EMI photomultiplier. The 5145 /sup 0/A line of a Coherent Radiation model 52 Ar+ ion laser was used to excite PL. The laser beam was expanded, having an intensity of about 100mW/cm/sub 2/ at the sample. During PL the sample was kept in air. EL measurements were performed in a N/sub 2/ purged 0.1 M Na/sub 2/S/sub 2/O/sub 8/ + 2.5 M KOH electrolyte. The electrode potential was pulsed between O V (SCE) (10 s) and -1.5 V (SCE) (1 s) while scanning the monochromator at 5/sup 0/A/s. A speccially constructed electrode holder enabled us to mount the electrodes in a reproducible way for taking the spectra.« less
  • We report a study of the influence of high intensity laser light on the optical properties and exciton relaxation dynamics in CdSe nanocrystals passivated by tri-n-octylphosphine oxide and dispersed in the optically clear poly(butylmethacrylate) polymer. Sample irradiation by 3 ps duration laser pulses at 527 nm leads to the blueshift of the maximum of the lowest-energy exciton absorption band and to the disappearance of a long-wavelength absorption slope in the 600-800 nm region that we attribute to Rayleigh scattering. The photomodification rate is approximately proportional to the second to third power of the light intensity and strongly temperature dependent. Themore » shift of the absorption band is related to the reduction of the nanocrystal (NC) size. The disappearance of the Rayleigh scatter is explained as a modification of the NC surface ligands and their immediate surroundings due to an increase in the local temperature.« less
  • Photothermal techniques are widely used in thin film characterizations and are particularly useful in studying laser-induced damage in optical coatings. The specific applications include measuring weak absorption, characterizing thermal conductivity, detecting local defects, and monitoring laser-interaction dynamics and determining laser damage thresholds as well as thermal impedance at boundaries of multilayers. We take an overview of the principle of photothermal techniques, the various detection methods, and the progress made during the last decade in applying these techniques to optical thin films. The further potential and limitations of the techniques will also be discussed, with emphasis on {ital in situ} studiesmore » of laser interaction with thin films and local defects. {copyright} {ital 1997 Society of Photo-Optical Instrumentation Engineers.}« less
  • Polycrystalline thin films of n-type CdSe (thickness 1--2 {micro}m) were grown on Zn substrates by noncatalytic displacement plating using aqueous solutions of CdSO{sub 4} and SeO{sub 2} in acidic pH. Thickness measurement was performed by the chemical stripping method as well as by the capacitance method. The electrical characterization comprises ohmic contact study, resistivity, conductivity, and impedance measurements. The optical characterization was determined by photocurrent action spectrum and visible reflectance spectrum studies. Crystallographic structure and surface morphology were analyzed by X-ray diffraction and scanning electron microscopy. Average grain size of the order of micrometers and well-defined grain boundaries were observed.
  • In the present paper, investigations of CdSe loaded poly(diallyl dimethyl ammonium chloride) (PDADMAC) nanocomposites and pure PDADMAC synthesized by wet chemical technique have been carried out. Fourier transform infrared and X-ray diffraction analysis have been performed to reveal the structural details of pure polymer and polymer nanocomposite (PNC). The dielectric behavior of pure polymer and PNC has been recorded, which results in higher value of the real and imaginary part of dielectric constant for PNC, as compared with pure PDADMAC. The increase is attributed to the addition of CdSe quantum dots to the pure polymer. The contribution of ionic andmore » electronic polarization has been observed at higher frequency. The theoretical fitting of Cole-Cole function to the experimental data of dielectric constant of PNC and pure PDADMAC results in the determination of relaxation time and conductivity of space charge carriers. The CdSe loaded polymer nanocomposite has been used as an electrolyte in the battery fabrication with configuration Al/PNC/Ag{sub 2}O. The ac conductivity measurements have been carried out for both samples in a frequency window of 1 kHz–5 MHz and at different temperatures varying from 298 K to 523 K. Activation energy (E{sub a}) has been determined for pure polymer as well as PNC and is found to be less for PNC, as compared with pure polymer. Further, impedance measurement at different temperatures results in two frequency ranges corresponding to ionic conduction and blocking electrode effect. The value of bulk resistance for pure polymer and PNC has been found to be 3660 Ω and 442 Ω, respectively, at 298 K temperature. Electric modulus has been determined and is observed to support the dielectric constant data; it further reveals the deviation from Debye behavior at a higher frequency.« less