Absorption spectrum of thin films of KPb2(Cl1-xBrx)5 solid solutions

2017 ◽  
Vol 43 (10) ◽  
pp. 1222-1225
Author(s):  
V. K. Miloslavsky ◽  
E. N. Kovalenko ◽  
O. N. Yunakova ◽  
N. N. Yunakov
Keyword(s):  
Thin Films ◽  
Absorption Spectrum ◽  
Solid Solutions

Tailoring the optical properties of tin oxide thin films via gamma irradiation

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ateyyah M. Al-Baradi ◽  
Ahmed A. Atta ◽  
Ali Badawi ◽  
Saud A. Algarni ◽  
Abdulraheem S. A. Almalki ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Absorption Spectrum ◽  
Gamma Irradiation ◽  
Tin Oxide ◽  
Free Charge Carrier ◽  
Oxide Thin Films ◽  
Dispersion Parameters ◽  
Absorption Spectrum Fitting ◽  
Spectrum Fitting

Abstract In the current work, the optical properties of tin oxide thin films have been tailored via gamma irradiation for energy applications. The effect of Gamma radiation (50, 100, 150, 200 and 250 kGy) on the microstructural, absorption and oscillator parameters of SnO2 thin films has been investigated. XRD results reveal that the SnO2 films have the symmetry of the space group P42/mnm belonging to the tetragonal system. The crystallite size of γ-irradiated SnO2 thin film slightly increases as the irradiation dose increases. The allowed optical band gaps are estimated by applying various methods such as Tauc’s method, derivation of absorption spectrum fitting and absorption spectrum fitting approaches. The dispersion parameters are extracted from the dispersion curve of the real part of the refractive index. The single-effective-oscillator and Drude models for free charge carrier absorption are applied to obtain the dispersion parameters before and after γ-irradiation.

scholarly journals Thin-film chemical expansion of ceria based solid solutions: laser vibrometry study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hendrik Wulfmeier ◽  
Dhyan Kohlmann ◽  
Thomas Defferriere ◽  
Carsten Steiner ◽  
Ralf Moos ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
High Temperature ◽  
Film Thickness ◽  
Solid Solutions ◽  
Low Voltage ◽  
Excitation Frequency ◽  
Dimensional Change ◽  
Potential Core ◽  
Chemical Expansion

Abstract The chemical expansion of Pr0.1Ce0.9O2–δ (PCO) and CeO2–δ thin films is investigated in the temperature range between 600 °C and 800 °C by laser Doppler vibrometry (LDV). It enables non-contact determination of nanometer scale changes in film thickness at high temperatures. The present study is the first systematic and detailed investigation of chemical expansion of doped and undoped ceria thin films at temperatures above 650 °C. The thin films were deposited on yttria stabilized zirconia substrates (YSZ), operated as an electrochemical oxygen pump, to periodically adjust the oxygen activity in the films, leading to reversible expansion and contraction of the film. This further leads to stresses in the underlying YSZ substrates, accompanied by bending of the overall devices. Film thickness changes and sample bending are found to reach up to 10 and several hundred nanometers, respectively, at excitation frequencies from 0.1 to 10 Hz and applied voltages from 0–0.75 V for PCO and 0–1 V for ceria. At low frequencies, equilibrium conditions are approached. As a consequence maximum thin-film expansion of PCO is expected due to full reduction of the Pr ions. The lower detection limit for displacements is found to be in the subnanometer range. At 800 °C and an excitation frequency of 1 Hz, the LDV shows a remarkable resolution of 0.3 nm which allows, for example, the characterization of materials with small levels of expansion, such as undoped ceria at high oxygen partial pressure. As the correlation between film expansion and sample bending is obtained through this study, a dimensional change of a free body consisting of the same material can be calculated using the high resolution characteristics of this system. A minimum detectable dimensional change of 5 pm is estimated even under challenging high-temperature conditions at 800 °C opening up opportunities to investigate electro-chemo-mechanical phenomena heretofore impossible to investigate. The expansion data are correlated with previous results on the oxygen nonstoichiometry of PCO thin films, and a defect model for bulk ceria solid solutions is adopted to calculate the cation and anion radii changes in the constrained films during chemical expansion. The constrained films exhibit anisotropic volume expansion with displacements perpendicular to the substrate plane nearly double that of bulk samples. The PCO films used here generate high total displacements of several 100 nm’s with high reproducibility. Consequently, PCO films are identified to be a potential core component of high-temperature actuators. They benefit not only from high displacements at temperatures where most piezoelectric materials no longer operate while exhibiting, low voltage operation and low energy consumption.

Electronic absorption spectrum of solid solutions of the system RbI–AgI–CsI

2006 ◽  
Vol 32 (10) ◽  
pp. 961-966 ◽  
Author(s):  
O. N. Yunakova ◽  
V. K. Miloslavsky ◽  
E. N. Kovalenko
Keyword(s):  
Absorption Spectrum ◽  
Electronic Absorption Spectrum ◽  
Solid Solutions ◽  
Electronic Absorption

Thickness dependence of transient absorption spectrum for InGaN thin films

2003 ◽  
Vol 0 (7) ◽  
pp. 2606-2609
Author(s):  
M.-S. Nomura ◽  
M. Arita ◽  
S. Ashihara ◽  
S. Kako ◽  
M. Nishioka ◽  
...  
Keyword(s):  
Thin Films ◽  
Absorption Spectrum ◽  
Transient Absorption ◽  
Thickness Dependence ◽  
Transient Absorption Spectrum

Synthesis of InxGa1–xN solid solutions

2005 ◽  
Vol 220 (2/3) ◽  
Author(s):  
Isabel Kinski ◽  
Florian Maurer ◽  
Holger Winkler ◽  
Ralf Riedel
Keyword(s):  
Thin Films ◽  
Solid Solutions ◽  
Group Iii ◽  
Group Iii Nitride

AbstractFor the growth of group-III nitride thin films as well as GaN and AlN bulk phases precursors are widely used. Here, we introduce bulk phases of pure GaN, InN and solid solutions of In

Preparation and Properties of CuInS2 Thin-Film by Successive Ionic Layer Adsorption and Reaction (SILAR) Method

2007 ◽  
Vol 280-283 ◽  
pp. 877-880
Author(s):  
Zheng Guo Jin ◽  
Yong Shi ◽  
Ji Jun Qiu ◽  
Xiao Xin Liu
Keyword(s):  
Thin Films ◽  
Absorption Spectrum ◽  
Optical Absorption ◽  
Optical Absorption Spectrum ◽  
Photoelectron Spectra ◽  
Molar Ratio ◽  
Silar Method ◽  
X Ray ◽  
Cuins2 Thin Films ◽  
Ionic Layer

CuInS2 thin films were deposited on galss substrate by successive ionic layer absorption and reaction (SILAR) method at room temperature. CuCl2, InCl3, and Na2S were used as precursor materials. The thin films were obtained during the dipping of 20-40 cycles and after annealing in the N2 atmosphere at 500°C. The characterization of the film was carried out by X-ray diffraction, scanning electron microscopy, optical absorption spectrum and X-ray photoelectron spectra. Quantification of the XPS peaks shows that the molar ratio of Cu:In:S of the film is close to the stoichiometry of CuInS2. XRD result demonstrated that the formed compound is CuInS2 with chalcopyrites crystal structure. Direct band gap was found to be 1.5eV from optical absorption spectrum.

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