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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： Sara Marijan Luka Pavic Division of Materials Chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 *** transition from a predominantly phosphate glass network(ximpedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic *** contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation *** high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)*** scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism

impedance spectroscopy and DFT/TD-DFT studies of diyttrium trioxide for optoelectronic fields

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Journal of Rare Earths 2023年第4期41卷 605-612页

作者： Ali A.Alkathiri A.A.Atta Moamen S.Refat Sonam Shakya A.M.Hassanien Saud A.Algarni Emad M.A.Ahmed Sultan E.Alomariy Mohammed Alsawat Norah Algethami Department of Physics College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Chemistry Aligarh Muslim UniversityAligarh202002India Department of Physics Faculty of Science and Humanity Studies at Al-QuwayiyahShaqra UniversityAl-Quwayiyah11971Saudi Arabia

Yttrium(Ⅲ)oxide or so-called diyttrium trioxide(Y_2O_3)is an excellent candidate ceramic material for optoelectronic ***,electrical conductivity,and dielectric relaxation properties of bulk yttrium(Ⅲ)oxide were studied.X-ray diffraction(XRD)results indicate that the yttrium(Ⅲ)oxide compound has a crystalline cubic *** transform infrared(FTIR)technique was used to ascertain the chemical structure of the yttrium(Ⅲ)oxide *** spectroscopy was used to analyze frequency-dependent electrical properties as a function of temperature in the range of 303-423 K and frequency range of 0.1 Hz-2 *** spectroscopy parameters such as dielectric constant,dielectric loss,loss factor,electric modulus,and complex impedance of the yttrium(Ⅲ)oxide compound were *** Nyquist plot describes the complex impedance of the yttrium(Ⅲ)oxide for different *** universal Jonscher's power law was used for the analysis of the complex electrical conductivity of the yttrium(Ⅲ)oxide *** is found that the real(σ')and imaginary(σ")parts of the complex conductivity increase with increasing *** exponent frequency(s)equals unity,which confirms that the predominant conduction mechanism is a nearly constant loss(NCL)***/TD-DFT studies using B3LYP/LanL2DZ level of theory were used to provide comparable theoretical data and electronic energy gap of HOMO→LUMO.

关键词： Yttrium(Ⅲ)oxidel impedance spectroscopy DFT/TD-DFT Rare earths

Correlation between impedance spectroscopy and bubble-induced mass transport in the electrochemical reduction of carbon dioxide

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Journal of Energy Chemistry 2022年第4期31卷 500-507页

作者： Stefania Lettieri Juqin Zeng M.Amin Farkhondehfal Umberto Savino Marco Fontana Candido F.Pirri Adriano Sacco Center for Sustainable Future Technologies@Polito Istituto Italiano di TecnologiaVia Livorno 6010144 TorinoItaly Department of Applied Science and Technology Politecnico di TorinoCorso Duca degli Abruzzi 2410129 TorinoItaly

In the electrochemical conversion of carbon dioxide, high currents need to be employed to obtain large production rates, thus implying that mass transport of reactants and products is of crucial *** aspect can be investigated by employing a model that depicts the local environment for the reduction reactions. Simultaneously, electrochemical impedance spectroscopy, despite being a versatile technique, has rarely been adopted for studying the mass transport features during the carbon dioxide(CO_(2))electroreduction. In this work, this aspect is deeply analyzed by correlating the results of impedance spectroscopy characterization with those obtained by a bubble-induced mass transport modeling under controlled diffusion conditions on a gold rotating disk electrode. The effects of potential and rotation rate on the local environment are also clarified. In particular, it has been found that CO_(2) depletion occurs at high kinetics when the rotation is absent, giving rise to an increment of the competing hydrogen evolution reaction. This feature reflects in an enlargement of the diffusion resistance, which overcomes the charge transport one.

关键词： Carbon dioxide conversion impedance spectroscopy Mass transport Modeling Rotating disk electrode

impedance spectroscopy for quantum dot light-emitting diodes

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半导体学报:英文版 2023年第9期44卷 26-38页

作者： Xiangwei Qu Xiaowei Sun Institute of Nanoscience and Applications and Department of Electrical and Electronic EngineeringSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of Energy Conversion and Storage Technologies(Southern University of Science and Technology) Ministry of Educationand Shenzhen Key Laboratory for Advanced Quantum Dot Displays and LightingSouthern University of Science and TechnologyShenzhen 518055China

impedance spectroscopy has been increasingly employed in quantum dot light-emitting diodes(QLEDs)to investigate the charge dynamics and device *** this review,we introduce the mathematical basics of impedance spectroscopy that applied to *** particular,we focus on the Nyquist plot,Mott-Schottky analysis,capacitance-frequency and capacitance-voltage characteristics,and the d C/d V measurement of the *** impedance measurements can provide critical information on electrical parameters such as equivalent circuit models,characteristic time constants,charge injection and recombination points,and trap distribution of the ***,this paper will also discuss the disadvantages and limitations of these ***,this review provides a deeper understanding of the device physics of QLEDs through the application of impedance spectroscopy,offering valuable insights into the analysis of performance loss and degradation mechanisms of QLEDs.

关键词： quantum dot light-emitting diode impedance spectroscopy equivalent circuit model charge dynamics

impedance spectroscopy study on Mn_(1+x)Fe_(2-2x)Ti_xO_4(0≤x≤0.5) ferrites

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Journal of Central South University 2010年第6期17卷 1133-1138页

作者： KUMAR S BATOO K M PRAKASH R CHOI H K KOO B H SONG J I CHUNG H JEONG H LEE C G School of Nano and Advanced Materials Engineering Changwon National UniversityChangwon 641773Korea King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh 11451Saudi Arabia Department of Mechanical Engineering Changwon National UniversityChangwon 641773Korea Department of Precision & Mechanical Engineering and BK21 Eco-Friendly Heat & Cold Energy Mechanical Research Team Gyeongsang National U niversityTongyeong 650160Korea

The complex impedance spectroscopy and surface morphology of Mn1+xFe2-2xTixO4(0≤x≤0.5) system,prepared using a conventional solid state reaction technique,were *** impedance spectroscopy measurements were carried out at room temperature in the frequency range of 42-5 *** electrical processes in the samples were modeled in the form of an equivalent circuit made up of a combination of two parallel RC circuits attributed to grain and grain *** DC conductivity obtained by extrapolation of AC data using impedance spectroscopy and four-probe method increases at 10% doping of Ti *** energy-dispersive X-ray(EDX) pattern confirmed the homogeneous mixing of the Mn,Fe,Ti and O atoms in pure and doped ferrite samples.

关键词： spinel ferrite magnetic properties impedance spectroscopy Ti4+ ions doping

impedance spectroscopy of Ion Beam Mixed Cu/BaTiO_3 PTCR Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2001年第3期16卷 15-18页

作者：雷家珩 Coll. of Materials Sci. and Technol. Wuhan University of Technology Wuhan 430070 China

The positive temperature coefficient resistance ( PTCR) barium titanate ceramic samples have been prepared by the standard solid-state reaction method, and the ceramic samples have been treated by depositing copper films with magnetron sputtering method. The metallic copper films deposited on the ceramic substrates have been mixed at room temperature with argon ions in energy of 400 keV. Ion beam mixing induced modification of PTCR behavior of the ceramics was studied by using the ac complex impedance method and the resistance vs. temperature measurements . The results showed that room temperature resistance dramatically decreased and Curie point shifted toward higher temperature side for the ion beam mixed samples.

关键词： semiconducting barium titanate ceramics impedance spectroscopy ion beams mixing

Evaluation of Thermal Barrier Coatings Exposed to Hot Corrosion Environment by impedance spectroscopy

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Chinese Journal of Aeronautics 2011年第4期24卷 514-519页

作者： LIU Chao HUANG Hui NI Liyong ZHOU Chungen Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University Beijing 100191 China

In this investigation, impedance spectroscopy （IS） is used, as a non-destructive tool, to examine the hot corrosion behavior of thermal barrier coatings （TBCs） exposed to a mixture of 25wt% NaCl and 75wt% Na2SO4. The results show that the thermally grown oxide （TGO） formed along the top coat/bond coat interface is a mixed oxide layer, i.e. Cr2O3, （Ni, Co）（Cr, Al）2O4 spinel and NiO. The growth of TGO layer appears to follow the parabolic law. The resistance of TGO increases due to the increase of thickness when the number of cycles is less than 110. While for more than 110 cycles, the resistance of TGO decreases with the increase of porosity of TGO layer, even though the thickness of TGO layer increases. The nucleation and propagation of cracks within top coat increase the electrical resistance of top coat. The parameters in equivalent circuit could be used to characterize the degradation of TBCs.

关键词： thermal barrier coatings hot corrosion impedance spectroscopy crack mixed oxide

Characterization of the BaBiO_3-doped BaTiO_3 positive temperature coefficient of a resistivity ceramic using impedance spectroscopy with T_c=155℃

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Chinese Physics B 2011年第4期20卷 543-550页

作者：袁昌来刘心宇周昌荣许积文杨云 College of Materials Science and Engineering Central South University School of Material Science and Engineering Guilin University of Electronic Technology

BaBiO3-doped BaTiO3 （BB-BT） ceramic, as a candidate for lead-free positive temperature coefficient of resistivity （PTCR） materials with a higher Curie temperature, has been synthesized in air by a conventional sintering technique. The temperature dependence of resistivity shows that the phase transition of the PTC thermistor ceramic occurs at the Curie temperature, Tc = 155℃, which is higher than that of BaTiO3 （≤ 130 ℃）. Analysis of ac impedance data using complex impedance spectroscopy gives the alternate current （AC） resistance of the PTCR ceramic. By additional use of the complex electric modulus formalism to analyse the same data, the inhomogeneous nature of the ceramic may be unveiled. The impedance spectra reveal that the grain resistance of the BB-BT sample is slightly influenced by the increase of temperature, indicating that the increase in overall resistivity is entirely due to a grain-boundary effect. Based on the dependence of the extent to which the peaks of the imaginary part of electric modulus and impedance are matched on frequency, the conduction mechanism is also discussed for a BB-BT ceramic system.

关键词： BaBiO3-doped BaTiO3 positive temperature coefficient thermistor impedance spectroscopy high Tc

Analyzing impedance spectroscopy Results

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稀有金属材料与工程 2006年第A3期35卷 452-454页

作者： Yoed Tsur Sioma Baltianski Department of Chemical Engineering Technion-Israel Institute of TechnologyHails 32000Israel

In this contribution we briefly discuss several analysis techniques for impedance spectroscopy experiments.A number of different approaches,which differ even by the definition of the problem,are used in the *** aimed towards finding an equivalent *** aimed towards finding directly dielectric properties of the material under an assumed *** towards finding distribution of relaxation times,either parametric or point-by *** matter what the approach is,this will always be an ill-posed problem in the sense that there exist a large number of possible solutions that solve the problem (mathematically) equally *** some a-priori knowledge about the system must he *** addition,we should remember that the ultimate goal is to get physical insight about the system.

关键词： impedance spectroscopy equivalent circuits discrepancy-complexity plots time constant distributions

Evaluation of plasma sprayed YSZ thermal barrier coatings with the CMAS deposits infiltration using impedance spectroscopy

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Progress in Natural Science:Materials International 2012年第1期22卷 40-47页

作者： Musharaf Abbas Key Laboratory of Aerospace Materials & Performance(Ministry of Education) School of Materials Science and EngineeringBeihang Univerisity

The yttria-stabilized zirconia(YSZ) thermal barrier coatings(TBCs) prepared by atmospheric plasma spraying with different heat treatment period at the temperature of 1250 1C were studied in the present *** impedance spectroscopy(EIS) was employed to nondestructively examine the impedance and capacitance behavior of free standing YSZ coatings deposited by plasma spray with CMAS(calcium-magnesium-alumino-silicate) *** circuit was established on the basis of the biomodal structure in *** sintering behavior of the coatings can be reflected by the changes of resistance and capacitance of the *** EIS,the microstructure evolution of the coating with CMAS deposits was discussed in detail.

关键词： Calcium-magnesium-alumino-silicate Thermal barrier coatings Plasma spray impedance spectroscopy