Synthesis of Vanadium Oxide Colloidal Dispersions for Antistatic Coatings

1996 ◽  
Vol 432 ◽  
Author(s):  
Eric.D. Morrison
Keyword(s):  
Vanadium Oxide ◽  
Conduction Mechanism ◽  
Colloidal Particles ◽  
Small Polaron ◽  
Electronic Conductivity ◽  
Colloidal Dispersions ◽  
Thin Layers ◽  
Properties Of Coatings ◽  
Polaron Hopping ◽  
Dispersed Particles

AbstractVanadium oxide deposited in thin layers from aqueous colloidal dispersions exhibits electronic conductivity by a small polaron hopping conduction mechanism. Conductivity and static dissipative properties of coatings are unaffected by changes in humidity. Because vanadium oxide is highly colored, the deposition of effective antistatic coatings which are transparent and colorless requires that the percolative (networking forming) properties of the colloidal particles be maximized. The percolative properties of the colloid are strongly influenced by morphology of the dispersed particles and the extent to which they are well dispersed in the aquasol. These properties are determined by the synthetic route to the colloid. Vanadium oxide is the most potent antistatic agent known and has been found to provide antistatic properties even when as little as 1 milligram per square meter is used.

Small polaron hopping conduction mechanism in Fe doped LaMnO3

2011 ◽  
Vol 135 (5) ◽  
pp. 054501 ◽  
Author(s):  
Wasi Khan ◽  
Alim H. Naqvi ◽  
Maneesha Gupta ◽  
Shahid Husain ◽  
Ravi Kumar
Keyword(s):  
Conduction Mechanism ◽  
Small Polaron ◽  
Hopping Conduction ◽  
Polaron Hopping ◽  
Small Polaron Hopping

Highly conductive barium iron vanadate glass containing different metal oxides

2017 ◽  
Vol 89 (4) ◽  
pp. 419-428 ◽  
Author(s):  
Tetsuaki Nishida ◽  
Yukimi Izutsu ◽  
Mina Fujimura ◽  
Keito Osouda ◽  
Yuki Otsuka ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Conduction Mechanism ◽  
Marked Decrease ◽  
Small Polaron ◽  
Electric Resistivity ◽  
Electron Configuration ◽  
Polaron Hopping ◽  
Vanadate Glass ◽  
Type Semiconductor ◽  
Vanadate Glasses

Abstract20BaO·5ZnO·5Fe2O3·70V2O5 glass annealed at 450°C for 30 min showed a marked decrease in the electric resistivity (ρ) from 4.0×105 to 4.8 Ωcm, while 20BaO·5Cu2O·5Fe2O3·70V2O5 glass from 2.0×105 to 5.0 Ωcm. As for the conduction mechanism, it proved that n-type semiconductor model in conjugation with the small polaron hopping theory was most probable. Since ZnII and CuI have a 3d10-electron configuration in the outer-most orbital, Ga2O3- and GeO2-containing vanadate glasses were explored in this study. 20BaO·5Ga2O3·5Fe2O3·70V2O5 glass showed a less remarkable decrease of ρ from 4.5×105 to 100 Ωcm, and 20BaO·5GeO2·5Fe2O3·70V2O5 glass from 3.3×106 to 400 Ωcm. Activation energies for the conduction (Ea) of GeO2- and Ga2O3-contaning glasses before the annealing were respectively estimated to be 0.42 and 0.41 eV. It proved that barium iron vanadate glass with a smaller Ea value could attain the higher conductivity after the annealing at temperaures higher than the crystalization temperature.

Small polaron hopping conduction mechanism in Ni-doped LaFeO3

2010 ◽  
Vol 90 (22) ◽  
pp. 3069-3079 ◽  
Author(s):  
M. Wasi Khan ◽  
Shahid Husain ◽  
M.A. Majeed Khan ◽  
Maneesha Gupta ◽  
Ravi Kumar ◽  
...  
Keyword(s):  
Conduction Mechanism ◽  
Small Polaron ◽  
Hopping Conduction ◽  
Polaron Hopping ◽  
Small Polaron Hopping

ELECTRICAL BEHAVIOR OF SOME LANTHANUM-BASED RARE EARTH CMR MATERIALS

2005 ◽  
Vol 19 (23) ◽  
pp. 3619-3629 ◽  
Author(s):  
V. RAJA KUMARI ◽  
G. VENKATAIAH ◽  
P. VENUGOPAL REDDY
Keyword(s):  
Rare Earth ◽  
Conduction Mechanism ◽  
Small Polaron ◽  
Domain Boundary ◽  
Solid State Reaction Method ◽  
7 Tesla ◽  
Scattering Process ◽  
Rare Earth Ion ◽  
Polaron Hopping ◽  
Composition Formula

A lanthanum-based mixed rare earth manganite system with general composition formula La 0.33 Ln 0.34 Sr 0.33 MnO 3, (where Ln is a rare earth ion) has been prepared by the solid state reaction method. After usual characterization of these materials, a systematic study of the electrical resistivity both as a function of temperature (80–300 K) and magnetic field up to 7 Tesla was undertaken mainly to understand the conduction mechanism. On analyzing the experimental results, it has been concluded that the metallic (ferromagnetic) part of the resistivity (ρ) (below TP) fits with the equation ρ(T)=ρ0+ρ2T2+ρ4.5T4.5, indicating the importance of grain/domain boundary effects (ρ0), the electron-electron scattering process (ρ2T2) and the two magnon scattering process (ρ4.5T4.5). On the other hand, the paramagnetic insulating regime may be explained by using adiabatic small polaron hopping and variable range hopping mechanisms, thereby indicating that polaron hopping might be responsible for the conduction mechanism.

scholarly journals Suitability of Sm3+-Substituted SrTiO3 as Anode Materials for Solid Oxide Fuel Cells: A Correlation between Structural and Electrical Properties

Energies ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 4042 ◽  
Author(s):  
Saurabh Singh ◽  
Raghvendra Pandey ◽  
Sabrina Presto ◽  
Maria Paola Carpanese ◽  
Antonio Barbucci ◽  
...  
Keyword(s):  
Oxygen Content ◽  
Conduction Mechanism ◽  
Small Polaron ◽  
Solubility Limit ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Solid Solubility Limit ◽  
Polaron Hopping ◽  
Auto Combustion ◽  
Lower Oxygen

Perovskite anodes, nowadays, are used in any solid oxide fuel cell (SOFC) instead of conventional nickel/yttria-stabilized zirconia (Ni/YSZ) anodes due to their better redox and electrochemical stability. A few compositions of samarium-substituted strontium titanate perovskite, SmxSr1−xTiO3−δ (x = 0.00, 0.05, 0.10, 0.15, and 0.20), were synthesized via the citrate-nitrate auto-combustion route. The XRD patterns of these compositions confirm that the solid solubility limit of Sm in SrTiO3 is x < 0.15. The X-ray Rietveld refinement for all samples indicated the perovskite cubic structure with a P m 3 ¯ m space group at room temperature. The EDX mapping of the field emission scanning electron microscope (FESEM) micrographs of all compositions depicted a lower oxygen content in the specimens respect to the nominal value. This lower oxygen content in the samples were also confirmed via XPS study. The grain sizes of SmxSr1−xTiO3 samples were found to increase up to x = 0.10 and it decreases for the composition with x > 0.10. The AC conductivity spectra were fitted by Jonscher’s power law in the temperature range of 500–700 °C and scaled with the help of the Ghosh and Summerfield scaling model taking νH and σdc T as the scaling parameters. The scaling behaviour of the samples showed that the conduction mechanism depends on temperature at higher frequencies. Further, a study of the conduction mechanism unveiled that small polaron hopping occurred with the formation of electrons. The electrical conductivity, in the H2 atmosphere, of the Sm0.10Sr0.90TiO3 sample was found to be 2.7 × 10−1 S∙cm−1 at 650 °C, which is the highest among the other compositions. Hence, the composition Sm0.10Sr0.90TiO3 can be considered as a promising material for the application as the anode in SOFCs.

scholarly journals Study of charge transfer mechanism and dielectric relaxation of all-inorganic perovskite CsSnCl3

RSC Advances ◽  
2021 ◽  
Vol 11 (35) ◽  
pp. 21767-21780
Author(s):  
Mohamed Ben Bechir ◽  
Mohamed Houcine Dhaou
Keyword(s):  
Charge Transfer ◽  
Dielectric Relaxation ◽  
Monoclinic Phase ◽  
Conduction Mechanism ◽  
Small Polaron ◽  
Cubic Phase ◽  
Inorganic Perovskite ◽  
Charge Transfer Mechanism ◽  
Large Polaron ◽  
Olpt Model

The conduction mechanism in CsSnCl3 is interpreted through the following two approaches: the non-overlapping small polaron tunneling (NSPT) model (monoclinic phase) and the overlapping large polaron tunneling (OLPT) model (cubic phase).

Synthesis and Electrical Transport Property of Sr and Cu-Doped LaFeO3-Based Cathode Material for IT-SOFC

2013 ◽  
Vol 710 ◽  
pp. 33-36
Author(s):  
Jie Zhao ◽  
Jiang Fu ◽  
Yong Fu ◽  
Yong Chang Ma
Keyword(s):  
Cathode Material ◽  
Electrical Transport ◽  
High Performance ◽  
Small Polaron ◽  
Negative Temperature ◽  
Rare Earth Oxide ◽  
Intermediate Temperature ◽  
Charge Balance ◽  
Mixed Conductivity ◽  
Polaron Hopping

In order to accelerate the commercialization of SOFCs technology, the key is the development of high performance cathode materials operated at intermediate temperature. Sr and Cu doped rare earth oxide La1-xSrxFe1-yCu.yO3-δ (x=0.1, 0.3 ; y=0.1, 0.2, denoted as LSFCu-11, LSFCu-31 and LSFCu-32 ) were synthesized by solid state reaction method (SSR). The formation process, phase structure and microstructure of the synthesized samples were characterized using TG/DSC, XRD and SEM. The thermal expansion coefficients (TEC) of the samples were analyzed by thermal dilatometry. The electrical conductivities of the samples were measured with DC four-terminal method from 25 to 950 °C. The results indicate that the samples exhibit a single phase with orthorhombic and hexagonal perovskite structure after sintered at 1200 °C for 4h. The electrical conductivity of the samples increases with temperature up to a maximum value, and then decreases gradually. The small polaron hopping is regarded as the conducting mechanism for synthesized samples at T 550 °C. The negative temperature dependence occurring at higher temperature is due to the creation of oxygen vacancies for charge balance. LSFCu-32 has higher mixed conductivity (> 100 S·cm-1) at intermediate temperature and can meet the demand of cathode material for IT-SOFC. In addition, the average TECs of LSFCu-11, LSFCu-31 and LSFCu-32 are 1.22 × 10-6 K-1 , 1.30 × 10-6 K-1 and 1.34 × 10-6 K-1 respectively.

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