scholarly journals Analysis of the charging kinetics in silver nanoparticles-silica nanocomposite dielectrics at different temperatures

Nano Express ◽  
2021 ◽  
Author(s):  
Cedric Djaou ◽  
Christina villeneuve-faure ◽  
Kremena Makasheva ◽  
Laurent Boudou ◽  
Gilbert Teyssedre
Keyword(s):  
Silver Nanoparticles ◽  
Electric Field ◽  
Field Distribution ◽  
Electric Field Distribution ◽  
Lateral Spreading ◽  
Sio2 Layer ◽  
Single Plane ◽  
Force Microscopy ◽  
Electrostatic Coupling ◽  
The Impact

Abstract Dielectric nanocomposite materials are now involved in a large panel of electrical engineering applications ranging from micro-/nano-electronics to power devices. The performances of all these systems are critically dependent on the evolution of the electrical properties of the dielectric parts, especially under temperature increase. In this study we investigate the impact of a single plane of silver nanoparticles (AgNPs), embedded in a thin silica (SiO2) layer close to the surface, on the electric field distribution, the charge injection and the charge dynamic processes for different AgNPs-based nanocomposites and various temperatures in the range 25°C – 110°C. The electrical charges are injected locally by using an Atomic Force Microscopy (AFM) tip and the related surface potential profile is probed by Kelvin Probe Force Microscopy (KPFM). To get deeper in the understanding of the physical phenomena, the electric field distribution in the AgNPs-based nanocomposites is computed by using a Finite Element Modeling (FEM). The results show a strong electrostatic coupling between the AFM tip and the AgNPs, as well as between the AgNPs when the AgNPs-plane is embedded in the vicinity of the SiO2-layer surface. At low temperature (25°C) the presence of an AgNPs-plane close to the surface, i.e., at a distance of 7 nm, limits the amount of injected charges. Besides, the AgNPs retain the injected charges and prevent from charge lateral spreading after injection. At 110°C the amount of injected charge is increased in the nanocomposites compared to low temperatures. Moreover, the speed of lateral charge spreading is increased for the AgNPs-based nanocomposites. These findings imply that the lateral charge transport is favored in the nanocomposite structures by the closely situated AgNPs because of the strong electrostatic coupling between them.

Conducting Atomic-Force Microscopy Investigations on Thin Silicon Gate Oxides: Influence of Tip Shape and Humidity

2002 ◽  
Author(s):  
S. Kremmer ◽  
S. Peissl ◽  
C. Teichert ◽  
F. Kuchar
Keyword(s):  
Atomic Force Microscopy ◽  
Electric Field ◽  
Field Distribution ◽  
Electric Field Distribution ◽  
Water Film ◽  
Topographic Effects ◽  
Ambient Conditions ◽  
Force Microscopy ◽  
Atomic Force ◽  
Thin Silicon

Abstract Conducting Atomic-Force Microscopy (C-AFM) has a strong potential for the characterization of thin silicon oxides on the nanometer scale. Here we consider difficulties and possible errors that may arise during C-AFM experiments. Using electrostatic simulations it is shown that very sharp tips can cause an inhomogeneous electric field distribution leading to an error in the measured Fowler-Nordheim (FN) current. Further, it is found that a water film, which is ever present under ambient conditions, on the one hand homogenizes the electric field distribution but on the other hand decreases the resolution of the measurements. For increased oxide thickness this water film leads to a ring formation in the electric field maximum and therefore makes an interpretation of FN current maps difficult. The occurrence of protrusions after the applying of voltage pulses and voltage ramps to the sample is investigated by comparing experiments under ambient conditions with measurements in ultra high vacuum (UHV). From this comparison we can conclude that the observed protrusions are real topographic effects, when a water film is present on the surface. However, for UHV experiments on a baked sample it is not yet clear if the protrusions are due to charging effects or due to a reaction with a residual amount of water.

Change in Electric Field Distribution in Non-Reducing BaTiO3 Based-Dielectric Layer Loaded at High Temperature

2013 ◽  
Vol 566 ◽  
pp. 16-19
Author(s):  
Takafumi Okamoto ◽  
Akira Ando ◽  
Hiroshi Takagi
Keyword(s):  
Electric Field ◽  
Field Distribution ◽  
Electric Field Distribution ◽  
Intermediate Stage ◽  
Homogeneous Distribution ◽  
Hole Density ◽  
Kelvin Probe ◽  
Multilayer Ceramic Capacitors ◽  
Force Microscopy ◽  
Insulation Degradation

The electric field distributions in loaded dielectric layers of multilayer ceramic capacitors were investigated at several stages of insulation degradation for the load, using Kelvin probe force microscopy. The electric field distribution was found to be different at each stage of loaded time. Initially, the electric field was concentrated near the cathode, indicating that the insulation resistance near the anode decreased. Then, following the homogeneous distribution shown for an intermediate stage, the electric field eventually concentrated near the anode. This change indicates how insulation degradation occurs locally; this change can plausibly be explained by a hole density increase.

Numerical Simulation of High Frequency Electromagnetic Wave in Microwave Cavity for Soot Oxidation

2013 ◽  
Vol 459 ◽  
pp. 310-318 ◽  
Author(s):  
Haitham B. Al-Wakeel ◽  
Zainal Ambri Abdul Karim ◽  
Hussain Hamoud Al-Kayiem ◽  
Hasan Fawad
Keyword(s):  
Numerical Simulation ◽  
Electric Field ◽  
Penetration Depth ◽  
Field Distribution ◽  
High Frequency ◽  
Electric Field Distribution ◽  
Soot Oxidation ◽  
Microwave Cavity ◽  
Field Pattern ◽  
The Impact

Soot oxidation temperature by high frequency electromagnetic energy was proposed using numerical simulation by combining electromagnetic with transient thermal analyses. Equation of electric field distribution in a microwave cavity with perfect electric conductor surfaces and TE10 mode is formulated from Helmholtz equation. The dissipated heat distribution is calculated from the electric field distribution. Six study cases for electric field and dissipated heat distributions were implemented by using ANSYS software based on finite element method. The impact of dielectric sample properties, position, size and shape inside the microwave cavity were predicted. The results from the simulation of electric field and dissipated heat were compared with available data in literature and showed the validity of the analysis. It was found that the electric field forming hot spots at penetration depth and front corners of the soot sample and penetration depth is equal to 12mm but equal to 0 for samples with dimensions less than penetration depth. Dissipated heat pattern depend on electric field pattern and dielectric properties.

scholarly journals COMSOL modeling of the lightning-generated electric field distribution in a chain of insulators of a 115 kV power transmission line

2021 ◽  
Vol 2135 (1) ◽  
pp. 012006
Author(s):  
A F Cadena ◽  
J S Mendoza ◽  
H F Ibáñez
Keyword(s):  
Electric Field ◽  
Transmission Line ◽  
Field Distribution ◽  
Electric Field Distribution ◽  
Travelling Waves ◽  
Stable State ◽  
Comsol Multiphysics ◽  
Exposure Limits ◽  
A Chain ◽  
The Impact

Abstract The transmission lines installed in our city, to the outskirts of it and in the rest of the national territory produce a level of emissions of electric field, these levels vary depending on the physical disposition of the drivers, the distance between spans, the voltage level of the line, among others. These values must respect the exposure limits for individuals, as stipulated in Article 14 of RETIE. In this work will be developed a study of distribution of the electric field along a chain of insulators standard of tempered glass of a transmission line of 115 kV with the aid of the software COMSOL Multiphysics, to the impact of an atmospheric discharge on the storage cable with the help of ATPDraw software, taking into account variations in the value of the earthing resistance of the structure. With the electric field distribution values obtained by means of simulations carried out in the COMSOL Multiphysics software, comparisons are made of the magnitude of the obtained field, taking as a reference the stable state of the system without condition of pollutants. Initially a simulation of a transmission line of 115 kV is performed in the ATPDraw software, analyzing the lightning impulse generated on the guard cable, at different values of grounding resistance, to determine the waveform and reached value of overvoltage in the insulator chain. Then the overvoltage signal obtained with the help of ATPDraw software is recreated in the COMSOL Multiphysics software, to be able to visualize the distribution and behavior of the electric field along the chain, taking into account the different factors involved in the process, pollutants such as salinity, themes such as travelling waves etc. and thus determine possible line isolation failures by comparing the values achieved by simulating in COMSOL Multiphysics with respect to the CFO of the insulator chain.

scholarly journals Potential barrier behavior in BiCuVOX materials

Cerâmica ◽  
2011 ◽  
Vol 57 (344) ◽  
pp. 428-430
Author(s):  
S. M. Gheno ◽  
P. I. Paulin F. ◽  
M. R. Morelli
Keyword(s):  
Ionic Conductivity ◽  
Electric Field ◽  
Potential Barrier ◽  
Field Distribution ◽  
Low Temperatures ◽  
Electric Field Distribution ◽  
Electric Force ◽  
Force Microscopy ◽  
Potential Barriers ◽  
Electric Force Microscopy

The BiMeVOX materials appear being high attractive for applications at low temperatures when the ionic conductivity is the determining parameter. The occurrence of many types substitution was confirmed for numerous Me ions, but the greatest interest have been focused on the BiCuVOX materials. The objective of this study was to image the potential barriers in BiCuVOX. The sample was sintered for 4 h at 750 °C and the results show that the high density compound can be obtained. Simultaneously, topography and electric force microscopy (EFM) images are viewed side-by-side. EFM experiments were performed and the results show the maps of the electric field distribution on the surface of BiCuVOX. The formation of potential barrier was observed and the width and intensity were measured.

Reducing the impact of ELF electromagnetic fields of HV power cables on the environment by modeling the cable accessories

2015 ◽  
Vol 34 (4) ◽  
pp. 1016-1028 ◽  
Author(s):  
Nebojsa B. Raicevic ◽  
Nikola Raicevic
Keyword(s):  
Electric Field ◽  
Electromagnetic Fields ◽  
Field Distribution ◽  
Distribution System ◽  
Childhood Leukemia ◽  
Electric Field Distribution ◽  
Tangential Component ◽  
Content Type ◽  
Significant Research ◽  
The Impact

Purpose – Underground cables can produce higher electromagnetic fields directly above them than an overhead line. The majority of cable failures on distribution system are caused by defects in the cable accessories. Nowadays, significant research has been carried out worldwide into examining whether electricity, and in particular, the presence of electric and magnetic fields have an adverse impact on health, especially the occurrence of cancer and childhood leukemia. The purpose of this paper is to optimize the electric field distribution in underground cable accessories. This reduces the impact of the harmful effects of the fields on living beings and humans. Design/methodology/approach – Cable terminations and joints are designed to eliminate the stress concentration at the termination screen to avoid the breakdown of the cable and high values of electric field at these points. Any improvement in the cable termination and joints construction is of great interest. There are several methods for the solution of electric field distribution. These can be summarized as analytical, experimental, free-hand field mapping, analogue methods and numerical methods. In this paper cable accessories are modeled by using multilayer dielectric system and very thin deflector’s cones. Findings – This model includes specific insulators design and smart choice of electrodes position. Stress-grading nonlinear materials in form of tapes and tubes were used with much success. In order to optimize the cable joint parameters, two criteria were monitored – total electric field magnitude and magnitude of the tangential component. More than 30 percent is reduced impact of cables on the environment. Originality/value – In order to investigate the accuracy of the applied numerical model, various configurations of the cable accessories are studied. The first time is applied new Hybrid Boundary Elements Method on the protection of the environment.

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