DC Conductivity of Illite with Fly-Ash between 20 – 1050 °C

2015 ◽  
Vol 1126 ◽  
pp. 123-128 ◽  
Author(s):  
Ján Ondruška ◽  
Igor Štubňa ◽  
Viera Trnovcová ◽  
Tomáš Húlan ◽  
Libor Vozár
Keyword(s):  
Activation Energy ◽  
Phase Transformation ◽  
Fly Ash ◽  
Temperature Region ◽  
Dc Conductivity ◽  
Charge Carriers ◽  
Conduction Activation Energy ◽  
Main Charge ◽  
Temperature Dependences ◽  
A Current

The temperature dependence of the electrical DC conductivity of fly-ash and illite-based ceramics was measured in the temperature range of 20 – 1050 °C. The measurements were done for illite samples with no fly-ash and fired illite added and illite samples containing 10 wt. %, 20 wt. %, 30 wt. %, and 40 wt. % of fly-ash and 0 wt. %, 10 wt. %, 20 wt. %, and 30 wt. % of fired illite. Addition of fly-ash substantially influences temperature dependences of the DC conductivity and introduces a temperature region with a high conduction activation energy which precedes the dehydroxylation. At the lowest temperatures, the main charge carriers are H+ and OH− ions, while at higher temperatures K+ and Na+ ions also play a role. The phase transformation metaillite -> Al-Si spinel is characterized with a current peak at 940 °C.

scholarly journals Microstructures and Electrical Conduction Behaviors of Gd/Cr Codoped Bi3TiNbO9 Aurivillius Phase Ceramic

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5598
Author(s):  
Huajiang Zhou ◽  
Shaozhao Wang ◽  
Daowen Wu ◽  
Qiang Chen ◽  
Yu Chen
Keyword(s):  
Activation Energy ◽  
Electrical Conduction ◽  
Impedance Spectrum ◽  
Element Distribution ◽  
Charge Carriers ◽  
High Resistivity ◽  
Aurivillius Phase ◽  
Conventional Solid State Reaction ◽  
Debye Relaxation ◽  
Conduction Activation Energy

In this work, a kind of Gd/Cr codoped Bi3TiNbO9 Aurivillius phase ceramic with the formula of Bi2.8Gd0.2TiNbO9 + 0.2 wt% Cr2O3 (abbreviated as BGTN−0.2Cr) was prepared by a conventional solid-state reaction route. Microstructures and electrical conduction behaviors of the ceramic were investigated. XRD and SEM detection found that the BGTN−0.2Cr ceramic was crystallized in a pure Bi3TiNbO9 phase and composed of plate-like grains. A uniform element distribution involving Bi, Gd, Ti, Nb, Cr, and O was identified in the ceramic by EDS. Because of the frequency dependence of the conductivity between 300 and 650 °C, the electrical conduction mechanisms of the BGTN−0.2Cr ceramic were attributed to the jump of the charge carriers. Based on the correlated barrier hopping (CBH) model, the maximum barrier height WM, dc conduction activation energy Ec, and hopping conduction activation energy Ep were calculated with values of 0.63 eV, 1.09 eV, and 0.73 eV, respectively. Impedance spectrum analysis revealed that the contribution of grains to the conductance increased with rise in temperature; at high temperatures, the conductance behavior of grains deviated from the Debye relaxation model more than that of grain boundaries. Calculation of electrical modulus further suggested that the degree of interaction between charge carriers β tended to grow larger with rising temperature. In view of the approximate relaxation activation energy (~1 eV) calculated from Z’’ and M’’ peaks, the dielectric relaxation process of the BGTN−0.2Cr ceramic was suggested to be dominated by the thermally activated motion of oxygen vacancies as defect charge carriers. Finally, a high piezoelectricity of d33 = 18 pC/N as well as a high resistivity of ρdc = 1.52 × 105 Ω cm at 600 °C provided the BGTN−0.2Cr ceramic with promising applications in the piezoelectric sensors with operating temperature above 600 °C.

Phase transformation of high aluminium fly ash in carbothermal reduction–nitridation at high temperatures

2014 ◽  
Vol 32 (4) ◽  
pp. 399-403
Author(s):  
M. H. Fang ◽  
H. T. Liu ◽  
Z. H. Huang ◽  
J. T. Huang ◽  
Y. G. Liu ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Fly Ash ◽  
High Temperatures ◽  
Carbothermal Reduction ◽  
High Aluminium

scholarly journals Термоэлектрические свойства твердых растворов (CuInSe-=SUB=-2-=/SUB=-)-=SUB=-1-x-=/SUB=-(In-=SUB=-2-=/SUB=-Te-=SUB=-3-=/SUB=-)-=SUB=-x-=/SUB=-

2022 ◽  
Vol 56 (1) ◽  
pp. 38
Author(s):  
Ч.И. Абилов ◽  
М.Ш. Гасанова ◽  
Н.Т. Гусейнова ◽  
Э.К. Касумова
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Solid Solutions ◽  
Figure Of Merit ◽  
Charge Carriers ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Figure ◽  
Mobility Of Charge Carriers ◽  
Temperature Dependences ◽  
Thermoelectric Coefficient

The results of studying the temperature dependences of electrical conductivity, thermoelectric coefficient, Hall mobility of charge carriers, total and electronic thermal conductivity, as well as phonon thermal resistance of alloys of (CuInSe2)1-x(In2Te3)x solid solutions at x=0.005 and 0.0075 are presented. The values ​​of these parameters for certain temperatures were used to calculate the values ​​of the thermoelectric figure of merit of the indicated compositions. It turned out that as the temperature rises, the thermoelectric figure of merit tends to grow strongly, from which it can be concluded that these materials can be used in the manufacture of thermoelements.

Lower ammoniation activation energy of CoN nanosheets by Mn doping with superior energy storage performance for secondary ion batteries

Nanoscale ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 5581-5590 ◽  
Author(s):  
Lin Zhu ◽  
Ziliang Chen ◽  
Yun Song ◽  
Pei Wang ◽  
Yingchang Jiang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Energy Storage ◽  
Anode Material ◽  
Current Density ◽  
Reversible Capacity ◽  
Mn Doping ◽  
High Reversible Capacity ◽  
Storage Performance ◽  
Secondary Ion ◽  
A Current

Mn0.33Co0.67N nanosheets were reported as a novel anode material for LIBs with a high reversible capacity close to 900 mA h g−1 after 150 cycles at a current density of 500 mA g−1, which is superior to 749 mA h g−1 of undoped CoN due to the enhancement of regeneration of Co–N bonds.

Electromigration of Electroplated Gold Interconnects

2005 ◽  
Vol 863 ◽  
Author(s):  
Steve Kilgore ◽  
Craig Gaw ◽  
Haldane Henry ◽  
Darrell Hill ◽  
Dieter Schroder
Keyword(s):  
Activation Energy ◽  
Diffusion Mechanism ◽  
Time To Failure ◽  
Ambient Temperatures ◽  
Temperature Coefficients ◽  
Current Stressing ◽  
Monitoring Technique ◽  
The Times ◽  
A Current

AbstractElectromigration tests were performed on passivated electroplated Au four terminal Kelvin line structures using the conventional in situ resistance monitoring technique. The stress conditions were a current density of 2.0 MA/cm2 with ambient temperatures ranging from 325°C to 375°C. The temperature coefficients of resistance (TCR) values were measured prior to current stressing to calculate the Joule heated film temperatures. The times to failure (lifetimes) for the Au line structures were considered as a 50% ΔR/R0 change. The median time to failure (t50%) was plotted against the inverse film temperature to determine the activation energy value as 0.59 ± 0.09 eV. Failure analysis of void location and suggested diffusion mechanism will be discussed.

Cerium oxide capping on Y-doped HfO2 films for ferroelectric phase stabilization with endurance improvement

2021 ◽  
Author(s):  
Kazuto Mizutani ◽  
Takuya HOSHII ◽  
Hitoshi WAKABAYASHI ◽  
Kazuo TSUTSUI ◽  
Edward Yi Chang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Phase Transformation ◽  
Cerium Oxide ◽  
Remnant Polarization ◽  
Ferroelectric Phase ◽  
Filament Formation ◽  
Conductive Filament ◽  
Phase Stabilization ◽  
Different Temperatures ◽  
Ferroelectric Switching

Abstract The effects of 1-nm-thick CeOx capping on 7.5-nm-thick Y-doped HfO2 films on the ferroelectric characteristics are investigated. From the ferroelectric characteristics of the samples annealed at different temperatures from 450 to 600oC and annealing durations, the time (τ) required to stabilize the ferroelectric phase at each temperature was shortened by the capping. The identical activation energy (Ea) of 2.65 eV for ferroelectric stabilization without and with capping suggests the same kinetics for phase transformation. However, an increase in the remnant polarization (Pr) was obtained. Only a few Ce atoms diffused into the underlying HfO2 film even after 600oC annealing. Ferroelectric switching tests revealed an improvement in endurance from 107 to 1010 by the capping, presumably owing to the suppression of conductive filament formation. Therefore, CeOx capping is effective in promoting the ferroelectric phase in HfO2 with high switching endurance.

Nachweis der Volumen-Ionisation in organischen Flüssigkeiten

1965 ◽  
Vol 20 (3) ◽  
pp. 394-400
Author(s):  
H. Bässler ◽  
P. Mayer ◽  
N. Riehl
Keyword(s):  
Positive Charge ◽  
Activation Energies ◽  
Dc Conductivity ◽  
Charge Carriers ◽  
Dielectric Liquid ◽  
Organic Liquids ◽  
Constant Field ◽  
Bulk Conductivity ◽  
Positive Ions ◽  
The Law

In order to study the bulk-conductivity in organic liquids measurements with blocking quartzelectrodes were made. When applying a constant field, a bulk-current through the dielectric liquid can be observed, which is decreasing exponentiallyjd(t)=j0_ exp {—t/R_C}+j0 exp {—t/R+ C}.R- and R+ are the bulk-resistivities for negative and positive charge-carriers, from which the bulk-conductivity of the liquid can be calculated. It is identical with the dc.-conductivity measured with conducting electrodes, that is it obeys the law:σ=σ01 exp { —E1/k T} +σ02 exp {—E.2/k T}.Therefore the generation of charge-carriers must be independent of the electrodes and the activation-energies E1 and E2 must correlate with ionisation within the liquid. The mobility of negative carriers is about two or three times that of positive ones. This fact leads to conclusions concerning the nature of the carriers. A tunnel-process is proposed to explain the discharging of positive ions at a metallic cathode.

Manganese-Doped CdGeAs2, ZnGeAs2 and ZnSiAs2 Chalcopyrites: A New Advanced Materials for Spintronics

2010 ◽  
Vol 168-169 ◽  
pp. 31-34 ◽  
Author(s):  
A.S. Morozov ◽  
L.A. Koroleva ◽  
D.M. Zashchirinskii ◽  
T.M. Khapaeva ◽  
S.F. Marenkin ◽  
...  
Keyword(s):  
Room Temperature ◽  
Magnetic Semiconductors ◽  
Dilute Magnetic Semiconductors ◽  
Charge Carriers ◽  
Advanced Materials ◽  
Temperature Dependences ◽  
P Type ◽  
Mn Doped ◽  
Curie Temperatures ◽  
Exchange And Superexchange Interactions

Based on the Mn-doped chalcopyrites CdGeAs2, ZnGeAs2 and ZnSiAs2, new dilute magnetic semiconductors with the p-type conductivity were produced. Magnetization, electrical resistivity and Hall effect of these compositions were studied. Their temperature dependences of magnetization are similar in form in spite of a complicated character, which is controlled by the concentration and mobility of the charge carriers. Thus, for T < 15 K, these curves are characteristic of superparamagnets and for T > 15 K, of a frustrated ferromagnet. In compounds with Zn these two states are diluted by a spinglass-like state. This specific feature is ascribed to attraction of Mn ions occupying neighboring sites and to competition between the carrier-mediated exchange and superexchange interactions. The Curie temperatures of these compounds are above room temperature. These are the highest Curie temperatures in the AIIBIVCV2:Mn systems.

scholarly journals The effect of annealing temperature on the structural, optical, and electrical properties of CdS films

2010 ◽  
Vol 25 (1) ◽  
pp. 189-196 ◽  
Author(s):  
Hulya Metin ◽  
Mehmet Ari ◽  
Selma Erat ◽  
Semra Durmuş ◽  
Mehmet Bozoklu ◽  
...  
Keyword(s):  
Activation Energy ◽  
Phase Transformation ◽  
Electrical Properties ◽  
Electronic Transport ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Urbach Energy ◽  
Band Gap Energy ◽  
Optical And Electrical Properties ◽  
Gap Energy

Cadmium sulfide (CdS) photocatalyst films were grown on glass by chemical bath deposition (pH 9.4, 70 °C) and then annealed in nitrogen from 423 K to 823 K in steps of 100 K. The XRD crystallite size increases in a sigmoidal manner from 60 nm to 100 nm while the optical band gap energy decreases from 2.42 eV to 2.28 eV. This trend is paralleled by the decreasing Urbach energy, but only up to 623 K, where it increases again. This is the temperature where the Cd effectively surpasses the phase transformation from cubic to hexagonal, and the activation energy for electronic transport drops by a factor of nearly two.

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