Optical Temperature Sensing Behavior Through Stark Sublevels Transitions of Green and Red Upconversion Emissions for Er3+–Yb3+–Li+ Codoped TiO2 Phosphors

The Er3+–Yb3+–Li+ codoped TiO2 phosphors have been prepared by sol–gel method. The green and red upconversion emissions were observed under a 976 nm laser diode excitation, which were ascribed to 2H11/2→4I15/2, 4S3/2(I)/4S3/2(II)→4I15/2, and 4F9/2(I)/4F9/(2II)→4I15/2 transitions of Er3+ Stark sublevels. The fluorescence intensity ratios (FIR), which are corresponding to the transitions of 2H11/2/(4S3/2(I)+4S3/2(II)→4I15/2, 4S3/2(I)/4S3/(2II)→4I15/2, and 4F9/2(I)/4F9/2(II)→4I15/2, have been studied as a function of temperature in the range of 303 ∼ 673 K. The temperature sensitivities have been calculated at the maximum value of 0.0020 K-1, 0.0015 K-1, and 0.0011 K-1 at the temperatures of 427 K, 350 K, and 273 K for the three coupled energy level transitions, respectively. The Er3+–Yb3+–Li+ codoped TiO2 phosphor with different temperature sensitivities by Stark sublevels indicated that it is a promising material for application in optical temperature sensing at a wide range of temperature.

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Optical Thin Films of Metal Oxides Produced by the Sol-Gel Method for Photovoltaic Applications

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.293.83 ◽

2019 ◽

Vol 293 ◽

pp. 83-95

Author(s):

Marek Szindler

Keyword(s):

Thin Films ◽

Optical Properties ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Light Transmission ◽

Sol Gel ◽

Thin Layers ◽

Gel Method ◽

Sol Gel Method ◽

Wide Range

The use of thin films in optoelectronic and photovoltaic devices is aimed at improving the physical properties of the substrate material. The modification of the surface of the silicon substrate is thus one of the greatest challenges in research on photovoltaic materials, in order to achieve even greater efficiency or better adapt their properties depending on the application. The technologies of applying layers vary depending on the effect to be obtained and the material from which the layer is formed. In practice, the most common method is chemical vapor deposition and physical vapor deposition, and the most commonly applied optical materials are SiO2, TiO2 and Si3N4.This paper presents the results of investigations on morphology and optical properties of the prepared aluminium oxide thin films. Thin films were prepared with use of sol-gel spin coating method. Surface morphology studies were carried out using an atomic force microscope. To characterize the surface of the thin films, 3D images and histograms of the frequency of individual inequalities were made. In order to characterize the optical properties of Al2O3 thin films, the reflectance and light transmission tests were performed using a spectrophotometer. Optical constants were determined using a spectroscopic ellipsometer. Results and their analysis show that the sol-gel method allows the deposition of homogenous thin films of Al2O3 with the desired geometric characteristics and good optical properties. Uniform, continuous thin layers with a roughness not exceeding a few nanometres were deposited. Their deposition enabled to reduce the reflection of light from the polished substrate below 15% in a wide range (425-800nm) while maintaining high transparencies (over 90%). The obtained results causes that mentioned thin films are good potential material for optics, optoelectronics and photovoltaics.

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Synthesis and Ferroelectric Properties of Sr- and Nb-codoped Bi4−xSrxTi3−xNbxO12 Thin Films by Sol-Gel Method

MRS Proceedings ◽

10.1557/proc-688-c4.14.1 ◽

2001 ◽

Vol 688 ◽

Author(s):

Hirofumi Matsuda ◽

Takashi Iijima ◽

Hiroshi Uchida ◽

Isao Okada ◽

Takayuki Watanabe ◽

...

Keyword(s):

Thin Films ◽

Curie Temperature ◽

Spin Coating ◽

Single Phase ◽

Ferroelectric Properties ◽

Sol Gel ◽

Metal Alkoxide ◽

Gel Method ◽

Maximum Value ◽

Chemical Solutions

AbstractFerroelectric Bi4Ti3O12 (BIT) thin films were modified by the substitution of Sr2+ ions for Bi3+ ions and of Nb5+ for Ti4+ (codoping) by spin-coating and decomposition of chemical solutions of metal-alkoxide materials (the nominal compositions of Bi4−xSrxTi3−xNbxO12 where x=0.0, 0.5, 1.0, 1.5). Single-phase thin films were crystallized above 550°C with BIT-type structure. The ferroelectric properties were found, though, with the values of Pr=10 μC/cm2 Ec=100 kV/cm, εr=300, and tanδ<5 % for Bi3.5Sr0.5Ti2.5Nb0.5O12 (x=0.5) annealed at 650 °C. Perhaps due to the lowering of the Curie temperature with increasing x, the maximum value of δr increased.

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Upconversion Emissions of Er3+-doped Yb2Ti2O7Powders by Sol-gel Method

ACTA PHOTONICA SINICA ◽

10.3788/gzxb20114001.0064 ◽

2011 ◽

Vol 40 (1) ◽

pp. 64-67

Author(s):

曹保胜 CAO Bao-sheng ◽

孙翼 SUN Yi ◽

关全寅 GUAN Quan-yin

Keyword(s):

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Upconversion Emissions

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Temperature Effects in Up-Conversion Processes of Erbium - Ytterbium Doped Oxyfluoride Silicate Glass

Latvian Journal of Physics and Technical Sciences ◽

10.2478/v10047-008-0028-0 ◽

2008 ◽

Vol 45 (6) ◽

pp. 47-54

Author(s):

J. Grube ◽

A. Sarakovskis ◽

L. Dimitrocenko ◽

M. Springis

Keyword(s):

Silicate Glass ◽

Laser Diode ◽

Fluorescence Intensity ◽

Temperature Effects ◽

Intensity Ratio ◽

Temperature Sensing ◽

Fluorescence Intensity Ratio ◽

Oxyfluoride Glass ◽

Potential Applicability ◽

Conversion Spectrum

Temperature Effects in Up-Conversion Processes of Erbium - Ytterbium Doped Oxyfluoride Silicate GlassEr3+- Yb3+doped oxyfluoride glass has been synthesized and investigated. It was found that the up-conversion spectrum of the sample excited by a 980 nm laser diode is highly dependent on the temperature of the sample. Using fluorescence intensity ratio technique the green up-conversion emissions at 525 nm and 550 nm were studied in detail in the temperature range 120-600 K. The potential applicability of the obtained results in the field of the temperature sensing is discussed.

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Preparation of ultrafine silicon oxycarbide fiber mats via electrospinning/sol–gel method: Investigation of the solution spinnability

International Journal of Modern Physics B ◽

10.1142/s0217979220400044 ◽

2019 ◽

Vol 34 (01n03) ◽

pp. 2040004

Author(s):

Yixuan Wang ◽

Ting Zhang ◽

Xiaoyu Yue ◽

Junyao Wu ◽

Wei Gao

Keyword(s):

Sol Gel ◽

Silicon Oxycarbide ◽

Solution Viscosity ◽

Free Standing ◽

Electrospinning Technique ◽

Fiber Mats ◽

Gel Method ◽

Sol Gel Method ◽

Wide Range ◽

Gel Preparation

Ultrafine silicon oxycarbide (SiOC) fiber mats were prepared through a sol–gel method combined electrospinning technique. The influence of sol–gel solution viscosity on its spinnability has been studied. By partially removing solvents after the sol–gel preparation, the solution could be stably spun and resulted in fiber mats with an average fiber diameter of 560 nm. The formation, morphology and composition of the SiOC fiber mats have been studied by TGA, FT-IR, SEM, XPS and XRD. Due to flexibility and free-standing property, the SiOC fiber mats will have a wide range of applications.

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Yb3+-Concentration dependent upconversion luminescence and temperature sensing behavior in Yb3+/Er3+ codoped Gd2MoO6 nanocrystals prepared by a facile citric-assisted sol–gel method

Inorganic Chemistry Frontiers ◽

10.1039/c7qi00497d ◽

2017 ◽

Vol 4 (12) ◽

pp. 1987-1995 ◽

Cited By ~ 78

Author(s):

Peng Du ◽

Xiaoyong Huang ◽

Jae Su Yu

Keyword(s):

Upconversion Luminescence ◽

Sol Gel ◽

Temperature Sensing ◽

Gel Method ◽

Sol Gel Method ◽

Sensor Sensitivity ◽

Optical Thermometry ◽

Upconversion Nanocrystals

Er3+/Yb3+-Codoped Gd2MoO6 upconversion nanocrystals with high sensor sensitivity and wide operation range were demonstrated for non-contact optical thermometry.

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Heterogeneous Electro-catalysis by Ni(III/II)Cyclam Embedded in a Sol-gel Matrix

10.14293/p2199-8442.1.sop-chem.piphwd.v1 ◽

2014 ◽

Author(s):

Ariela Burg ◽

Dror Shamir ◽

Lina Apelbaum ◽

Eric Maimon ◽

Dan Meyerstein

Keyword(s):

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Preliminary Results ◽

Wide Range ◽

Electro Catalysis ◽

Catalytic Processes ◽

Environmental Importance

The simplicity of preparation \(SiO_2\) matrices, using the sol-gel method, as well as the relative inertness and stability of the matrices, have promoted their use in a wide range of processes. It was decided to check whether sol-gel matrices in which a redox agent is entrapped, can be used as an electro-catalyst. Methyl amines such as \((CH_{3})_{n}NH_{3-n}\), are formed as waste in dyestuff, agriculture, and catalysis industries. Therefore, their treatment has environmental importance. In this study Ni(III)Cyclam was chosen as an electro-catalyst for methyl amines treatment. Preliminary results indicate that such electro-catalytic processes based on sol-gel electrodes can be developed.

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Upconversion luminescence and temperature-sensing properties of Ho3+/Yb3+-codoped ZnWO4phosphors based on fluorescence intensity ratios

RSC Advances ◽

10.1039/c7ra05846b ◽

2017 ◽

Vol 7 (64) ◽

pp. 40046-40052 ◽

Cited By ~ 25

Author(s):

Xiaona Chai ◽

Jun Li ◽

Xusheng Wang ◽

Yanxia Li ◽

Xi Yao

Keyword(s):

Solid State ◽

Fluorescence Intensity ◽

Solid State Reaction ◽

Upconversion Luminescence ◽

Solid State Reaction Method ◽

Temperature Sensing ◽

Level System ◽

Reaction Method ◽

Sensing Properties ◽

Intensity Ratios

Ho3+/Yb3+-codoped ZnWO4phosphors were synthesized using a solid state reaction method. The optical temperature sensing properties of ZnWO4:0.01Ho3+/0.15Yb3+phosphors have been discussed by using four-level system and the intensity ratio between the red and green emissions.

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Preparation and Ethanol Sensing Properties of ZnO Nanoparticles via a Novel Sol-Gel Method

ISRN Nanotechnology ◽

10.5402/2012/879480 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

A. Ahmadi Daryakenari ◽

M. Ahmadi Daryakenari ◽

Y. Bahari ◽

H. Omivar

Keyword(s):

Zno Nanoparticles ◽

Gas Sensing ◽

Sol Gel ◽

Ethanol Vapor ◽

Ambient Conditions ◽

X Ray Diffraction ◽

Gel Method ◽

Sol Gel Method ◽

Maximum Value ◽

Ethanol Sensing

ZnO nanoparticles were prepared using a novel sol-gel method. Chemical reactions were carried out between zinc acetate and methanol under ambient conditions using monoethanol amine (MEA) as surfactant and subsequent heating at . The powders were calcined, pressed into pellets, and presintered. The properties of the product were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectra. For gas sensing experiment, ethanol was used as testing gas. The gas sensing results showed that the maximum value for detecting of 1000 ppm ethanol vapor was 25 at an operating temperature of .

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