Showing papers in "Ferroelectrics in 2023"

Electrochemical deposition of Ag nanoparticles on ITO-coated glass: effect of different cyclic voltammetry scan rates on Ag deposition

Abstract: Abstract This work aims to investigate the effect of different cyclic voltammetry scan rates on silver nanoparticles deposition on ITO-coated glass aiming to obtain improve its optical and electrical properties. The deposition was evaluated using different physical, chemical and optical characterization techniques, such as SEM, XRD, FTIR, UV–visible and electrochemical tests. Cyclic voltammetry was used to measure the Ag deposition at two different scan rates (20 CV at 10 mV/s and 100 CV at 30 mV/s). The characterization results have confirmed the formation of a homogeneous crystal layer of silver on ITO, which exhibited high transmittance in the visible light region. According to the cyclic voltammetry measurements, the outer spheres of the Ag NPs associated with the redox reaction illustrate the typical reduction and oxidation waves of Ag in the range of (−100 to +700) mV. The quantification using Cyclic voltammetry measurements has shown that the Ag nanoparticles deposition on ITO thin films are inversely proportional to the scan rates; in other words, higher deposition is obtained at lower scan rates.

Multi-scale deep neural network for fault diagnosis method of rotating machinery

Abstract: Abstract In recent years, deep learning technology has shown great potential in the fault diagnosis of rotating machinery based on vibration signals. However, the feature extraction and noise robustness still need to be improved. To this end, we propose a multi-scale deep neural network fault diagnosis method. Firstly, multi-scale down sampling of time-domain vibration signals. Next, the attention long short-term memory network and the fully convolutional neural network of the multi-scale convolution kernel are used for feature extraction. Then, a fusion module is utilized to fuze the extracted features. The proposed method is evaluated on the public bearing datasets. Experimental results demonstrate that the proposed method can achieve high accuracy and noise robustness.

A brief review on hydrophone based on PVDF piezoelectric film

Abstract: Abstract Poly(vinylidene fluoride) (PVDF) has been a kind of particularly attractive piezoelectric materials for its excellent piezoelectric property. Due to its light weight, impedance characteristic is very similar to water, and good mechanical flexibility, PVDF piezoelectric film is very suitable for the field of hydrophones. Although the piezoelectric ceramic hydrophone has been widely used, but due to the disadvantage of high inherent frequency and fragile characteristics of the piezoelectric ceramics slice, the development of the piezoelectric hydrophone is limited. The application of PVDF piezoelectric film has solved many problems encountered in the use of piezoelectric ceramics. In this article, the classification of hydrophone is briefly introduced at first, and then the current status of hydrophone research is involved. And then, by analyzing the electrical equivalent model of the PVDF piezoelectric sensitive unit, the signal conditioning circuit of the PVDF piezoelectric hydrophone is summarized as well. After that, the current status of PVDF hydrophone research is discussed. Finally, a summary of all the work listed in this article is given and an outlook of PVDF hydrophone is proposed.

Modeling and control of rate-dependent hysteresis characteristics of piezoelectric actuators based on analog filters

Abstract: Abstract The hysteresis nonlinearity and rate dependence of piezoelectric actuators seriously affect their positioning accuracy in precise positioning. Proper compensation needs to be given to improve the positioning accuracy of the actuator. In this paper, the static hysteresis characteristics are described by improving the BP neural network model based on the adaptive particle swarm optimization algorithm, and the PI model is used as the hysteresis factor by the extended space method to realize the multi-valued mapping of hysteresis nonlinearity. And input three types of voltage signals, compare and analyze the experimental data and model prediction output, and use the maximum relative error and root mean square error as the evaluation indicators to prove the accuracy of the built model. Based on the improved BP neural network model, a second-order low-pass analog filter is introduced to construct a rate-dependent hysteresis model. Comparing and analyzing the rate-dependent hysteresis model and the static hysteresis model, the experimental results show that when the signal frequency is 10 Hz, 40 Hz, and 100 Hz, the predicted output of the rate-dependent hysteresis model is compared with that of the static hysteresis model, and the root mean square error decreases by 46.3%. %, 59.6%, and 65.1%, the model can more accurately describe the hysteresis characteristics of piezoelectric actuators. Finally, a rate-dependent hysteresis inverse model is established, and the rate-dependent hysteresis inverse model is used as a feedforward combined with a single neuron network PID control to form a composite controller, and the experimental verification is carried out. The results show that the maximum error between the composite controller and the actual expectation is only 2.15%. Therefore, the established model can accurately express the rate-dependent hysteresis characteristics of piezoelectric actuators, and the use of a composite controller can effectively reduce the accuracy error caused by the hysteresis nonlinear characteristics of piezoelectric actuators.

Features of the direction of the magnetization vector in a two-layer Fe/LiNbO3 system

Abstract: Abstract Two-layer ferromagnet/ferroelectric heterostructures were studied, in which iron was used as the ferromagnetic layer and 41°Y-cut lithium niobate was used as the ferroelectric substrate. It is shown that when an electric field is applied in the region of 50 V to a ferroelectric lithium niobate substrate, changes in the direction of the magnetization vector of the ferromagnetic layer are recorded.

Investigational studies of crystalline, optical, dielectric, thermal, mechanical, second besides third order nonlinear optical properties of urea itaconic acid solitary material

Abstract: Abstract In this research work, we used low temperature growth technique (Slow cooling method) for the growth of nonlinear optical and antimicrobial activity of fully-fledged organic Urea Itaconic acid (UITA) crystal. The model was crystallised with a monoclinic crystal structure in the centrosymmetric space group P21/c. The single crystal X-ray diffraction (SXRD) method was used to determine the crystal characteristics of the compounds. To validate the presence of separate functional groups, a Fourier transform infra-red test is utilised. The crystallinity and phase purity of the entire crystal is confirmed by the X-ray diffraction pattern of the detected Bragg peaks. The optical transmission window and shorter UITA wavelength cut-off were established using UV-Vis-NIR studies. Defects were also analysed by the dielectric loss, dielectric constant and AC conductivity studies. The mechanical stability of growing crystal was required to identify using Vickers microhardness analysis and by the Hays-Kendall approach, the effect of hole size (ISE) and the proportional stability model (PSRM) was adequately explained. Using energy dispersion spectrometry, the presence of urea and itaconic acid was confirmed. The differential thermal analysis (DTA) and thermogravimetric (TG) technique were studied by thermal effects of crystal. Using Z scan method the good third order nonlinear response for different planes (1 0 0), (0 0 1) and (1 1 − 1) of the UITA crystal sample were determined. Potentially threatening microbe’s activity utilised to analysis antimicrobial chattels. UITA sample were taken into the solubility and width of the metastable region. The good crystal perfection is showed that the grown crystals using by HRXRD and etching studies. Using on classical nucleation theory, the final nucleation constraints such as phase to phase strain, Gibbs free energy transformation, critical radius, molecular count in the critical nucleus and nucleation rate were calculated for the UITA sample. Second Order NLO behaviour of the grown crystals were confirmed by Kurtz powder procedure.

A new multi-piezoelectric input synchronized switch harvesting on inductor circuit

Abstract: Abstract This paper has proposed a multi-piezoelectric input synchronized switch harvesting on inductor (MI-SSHI) circuit. The MI-SSHI circuit is mainly composed of an extreme detector unit and synchronized switch harvesting on inductor (SSHI) units. The extreme detector unit generates real-time control signals. Since the principle of SSHI circuit, each voltage on piezoelectric element can be switched at different instant in a period. In this paper, two piezoelectric element inputs are selected as an example. The experimental result validates that the output power of the MI-SSHI circuit is improved by 11.67%, in comparison to the traditional S-SSHI circuit.

Research on sand blank preparation and sand mold NC precision milling technology

Abstract: Abstract In order to develop the preparation process of sand blank for NC milling requirements, the study of the material and the formula of sand blank are performed by experiment method. In order to obtain the optimal cutting parameters combination, the study is performed to evaluate the NC milling accuracy influence of sand mold for different cutting parameters by orthogonal experiment method. And the NC milling problems of sand mold such as avalanche angle, crack and uneven surface etc are solved by the above studies. The feasibility and effectiveness of the research findings are finally verified by the specific machining example. So, the whole technology solution of the preparation of sand blank and the NC precision milling of complex sand mold could be provided in this paper.

Reduction of leakage current and large enhancement of ferroelectric properties in Sb doped Bi4Ti3O12 ferroelectric thin film with Sb doped Bi2Ti2O7 as buffer layer

Abstract: Abstract Perovskite phase ferroelectric thin films Bi4-xSbxTi3O12 (Sb ( x )-BIT) and pyrochlore crystal phase thin films Bi2-ySbyTi2O7 (Sb ( y )-BTO) with different Sb concentration have been fabricated on Pt(111)/Ti/SiO2/Si(100) substrates through sol-gel method respectively. Test results show that the doping Sb can significantly reduce the leakage current of films. Especially when x = 0.04, y = 0.3 the leakage current characteristics of Sb ( 0.04 )-BIT and Sb ( 0.3 )-BTO both to achieve the optimal, and the ferroelectric properties Sb ( 0.04 )-BIT are also improved. By the same means, constructed the Sb ( 0.04 )-BIT / Sb ( 0.3 )-BTO system with Sb ( 0.3 )-BTO as buffer layer and Sb ( 0.04 )-BIT as ferroelectric layer. The properties of BIT ferroelectric thin films are improved by the doping of Sb element and the addition of buffer layer. This is mainly reflected in that compared to pristine BIT the leakage current of Sb ( 0.04 )-BIT / Sb ( 0.3 )-BTO system decreases rapidly from the initial 8.8 × 10−4 A/cm2 to the current 7.2 × 10−10 A/cm2, the residual polarization 2Pr of the system increases sharply from 9.5 to 70.8 µC/cm2 and fatigue endurance up to more than 1010 switching cycles.

Preparation and properties of three-dimensional dendritic NiCuP-supported nickel foam catalysts

Abstract: Abstract Hydrogen production by electrolysis of water is a very promising technology but is still limited by catalyst activity and/or catalyst poisoning after catalysis. Therefore, finding new catalysts is highly desirable. In this study, NiCuP-supported nickel foam (NiCuP/NF) catalyst was prepared by the hydrothermal method. The phase structure, morphology, and electrochemical catalytic performance of NiCuP/NF composite catalyst were studied by X-ray diffraction, scanning electron microscopy, and electrochemistry. The three-dimensional dendritic NiCuP/NF catalyst prepared by hydrothermal synthesis at 140 °C for 18 h showed uniform grain distribution. The catalyst was mainly composed of crystalline metal nickel, crystalline Ni2P, and crystalline Cu3P. The electrochemical characterization of the NiCuP/NF electrode displayed overpotentials of 149 and 261 mV at the current densities of 10 and 100 mA·cm−2, respectively. A lower value than that of the blank carrier electrode. The Nyquist plots obtained from the electrochemical impedance spectroscopy revealed significantly smaller charge transfer resistance Rct of the NiCuP/NF electrode than that of the blank electrode. As the resistance became smaller, the charge transfer rate became larger, leading to better electrocatalysis. The formation of 3 D dendritic morphology NiCuP/NF catalyst increased the number of active sites, thereby greatly improving the hydrogen evolution efficiency.

Luminescence study of samarium-doped Ca2KZn2(VO4)3 phosphor as a potential candidate for lighting and display device applications

Abstract: Abstract Ca2KZn2(VO4)3:Sm3+ phosphors have been prepared via the conventional solid state reaction method. Under 331 nm excitation, undoped Ca2KZn2(VO4)3 phosphor exhibits broad emission in the range of 400 nm to 600 nm, centered at the 515 nm emission wavelength. Whereas, Sm3+ doped Ca2KZn2(VO4)3 phosphor exhibited three intense emission bands around 567, 601 and 648 nm due to 4G5/2 − 6H5/2, 4G5/2 − 6H7/2 and 4G5/2 − 6H9/2 transition of Sm3+ ions, respectively. These results indicates that the synthesized Ca2KZn2(VO4)3:Sm3+ phosphors can be used as potential candidate for white light emitting diodes (WLEDs) and display devices.

Control of the LiFePO4 electrochemical properties via a pray-drying-assisted a solid-phase reaction route using Fe3(PO4)2 as iron precursor

Abstract: Abstract Fe3(PO4)2 as iron precursor was prepared by liquid phase method with FeSO4 as iron source, and then LiFePO4(LFP) was made by high-temperature solid state reaction. The adjustment of Fe and P content is beneficial to the precise control of Fe3(PO4)2 precursor components and ensure the excellent electrochemical performance of LiFePO4 materials. It is shown that pH is very critical to the contents of iron and phosphorus in Fe3(PO4)2, and a stoichiometric ratio of high-yield Fe3(PO4)2 can be obtained at a pH of six. After Fe3(PO4)2 is mixed with Li3PO4 and glucose, high-energy ball milling and spray-drying technology are used to thoroughly mix the mixtures and control their morphology of them. The as-prepared LiFePO4 maintains the microporous spherical morphology by high-temperature solid-state method, which is formed in spray drying. At 700 °C, the LFP/C material has reaching 156, 147, 137, 128, 111, 96 mAh g−1 at 0.2 C, 0.5 C, 1 C, 5 C and 10 C rate, respectively, and after 500 long loops for 5 C, the capacity retention still maintains 49%. LFP prepared with ferrous iron phosphate as precursor has good cycling performance.

Modeling of hollow cylinder piezoelectric resonator with current excitation by a double Legendre polynomial method

Abstract: Abstract This article presents an extension of the double Legendre polynomial method to model and evaluate the axisymmetric free vibration problem for the axially polarized piezoelectric resonator. The aim is to show the benefit of the employed method. The polynomial series was used to define the mechanical displacements and electrical potential at the same time. The proposed approach considerably improves computing efficiency by avoiding much of the numerical integration calculations. As a result, the electromechanical coupling coefficient shows that the fundamental mode is the most piezoactive mode in the structure. Furthermore, the electrical input impedance and field profiles are easily presented.

Study of the rare earth-based perovskite NdInO3: DFT approach

Abstract: Abstract In the present work, we study the structure, electronic and magnetic properties of the rare-earth-based perovskite NdInO3 material. For this purpose, we performed the density functional theory DFT calculations under the Quantum Espresso (QE) code. Also, we applied the norm-conserving pseudo-potentials without spin-orbit coupling (SOC) approximations. In fact, we use the Perdew–Burke–Ernzerhof generalized gradient approximation (GGA-PBE) to deduce the physical properties of the rare earth-based perovskite NdInO3. In particular, the total and partial density of states of the studied perovskite NdInO3 material have been deduced. The studied material exhibits both a half-metallic behavior and magnetic character. Moreover, the Nd-6d orbital is found to be the most contributing orbital in the conduction band (CB). Also, the In-1s orbital is contributing mostly in the (BC), while the O-2p orbital, is the most contributing one in the valence band (VB). In the spin-up channel, we computed the value 1.8 eV of the band gap. Such value confirms that the rare earth-based perovskite NdInO3 material, is a potential candidate for photovoltaic applications.

Piezoelectric hysteresis in ferroelectric ceramics in a weak electric field

Abstract: Abstract In this work, we studied the piezoelectric hysteresis effect induced by a weak dc electric field in ferroelectric ceramics. Precision measurements of the impedance spectra for the thickness vibrational mode of thin piezoceramic disks at different polarities of applied dc electric field were performed using the method and program of piezoelectric resonance analysis (PRAP). The field dependences of the complex piezoelectric constants of piezoelectric ceramics obtained by processing successively measured impedance spectra were analyzed and a physical interpretation of the results was proposed.

The influence of the cooling rate onto efficiency of the poling by field cooling of BaTiO3 ceramics

Abstract: Abstract The influence of the cooling rate during poling by cooling in a constant field of the barium titanate ceramics was studied by ex situ piezoresponse force microscopy measurements after macroscopic poling. The rearrangement of the domain structure and the value of the averaged local piezoelectric coefficient were shown to be largely determined by the cooling rate. It was revealed that the high cooling rate stimulated increasing the domain sizes, which in turn increased the average piezoelectric response due to a better alignment of the polarization.

Design and experimental investigation of magnetically coupling piezoelectric energy harvesting system based on galloping and vortex induced vibration

Abstract: Abstract This paper presents a magnetic coupling piezoelectric energy harvester based on galloping and vortex-induced vibration to scavenge low-speed wind. The influence of magnet spacing on the piezoelectric energy harvester is analyzed by using a mathematical model. The power generation performance of the energy harvester is explored by changing the magnet spacing. The experimental results show that the distance is negative related to the onset wind speed. Vortex induced vibration still make the system have voltage output. The output power can be effectively improved by increasing the magnet spacing while the magnetic force beyond a certain range can be ignored.

Pulsating mode in X-ray generators based on the SBN-61 crystal

Abstract: Abstract Currently, pyroelectric crystals are used in the development of new portable sources of X-ray and neutron radiation. Typically, X-rays are produced when pyroelectric crystals are heated or cooled. In this work, in an X-ray generator based on a ferroelectric crystal of barium-strontium niobate Sr0.61Ba0.39Nb2O6, the pulsations of the electron and X-ray flux were registered at a constant temperature when the gas pressure increased in the range 2·10−2–10−1 Torr. The electron flux had the shape of a cross in the crystal plane. The flash duration did not exceed 0.04 seconds. The observed effect is explained by the movement of domain boundaries on the depolarized crystal face in vacuum, resulting in a large surface charge and, accordingly, an electric potential, leading to the formation of a pulsed electron flux.

Nanoscale engineering of BaTiO3 using Y3+-Ta5+ dipoles

Abstract: Abstract BaTiO3 properties can be enhanced to improve capacitor energy storage density through electric-field ( E ) dipole engineering at the nanoscale ( E -DENS). E -DENS allows engineers to modify the internal E through dipole interactions. E -DENS of Ba[(Y3+,Ta5+)xTi1-2x]O3 with 0.0000 ≤ x ≤ 0.0500 are investigated by substituting Y3+-Ta5+ dipole pairs for Ti4+-Ti4+ non-dipolar pairs within the BaTiO3 structure. The Y3+ and Ta5+ ions are more polarizable than Ti4+ and are expected to increase the temperature at which the material becomes cubic and paraelectric. Room temperature XRD, UV-Vis-NIR, LCR, and resistivity analysis have been used to characterize Ba[(Y3+,Ta5+)xTi1-2x]O3 with 0.0000 ≤ x ≤ 0.0500.

Design and simulation of piezoelectric MEMS logic gates

Abstract: Abstract In this article, MEMS-based logic gates such as OR, AND, NOT, NOR, and NAND gates with functionalities similar to the electronic digital devices are designed and simulated. The key feature of these logic devices is that the mechanical cantilever structure of the basic piezo-actuator is adapted to operate like a particular digital logic gate based on the digital inputs. Complete analytical modelling for a single piezo-actuator with a correlation between its out-of-plane tip deflection with applied voltage is obtained. The proposed digital logic devices are further validated through simulation using the MEMS CAD tool CoventorWare.

Application of toroidal magnet excitation and hall sensor array in magnetic leakage field detection of rail surface defect

Abstract: Abstract To detect rail top surface defects, NdFeB toroidal permanent magnets were firstly used to excite the rail detection area, and the magnetic excitation direction was perpendicular to the rail direction. So that, the magnetic circuit can be analyzed, and the model was verified by finite element simulation. Secondly, the artificial rectangular defect samples were machined on the top surface of the rail, and the magnetic field data acquisition system was developed and equipped on the inspection vehicle. With that, a linear array which consisted of three-dimensional hall sensors was designed to detect the magnetic leakage field signal from the defect samples. Finally, the features of the leakage field signal in each dimension were extracted. And then, the length, width, and depth of the defects were predicted using BP neural network algorithm. The results indicate that the method can improve the excitation efficiency, and the average absolute errors of prediction for defect length, width, and depth were 1.43 mm, 1.01 mm, and 0.63 mm respectively.

Preparation and optical properties of ZnO and ZnO/ZnAlO heterojunction films by magnetron sputtering

Abstract: Abstract ZnO and ZnO/ZnAlO heterojunction films with different concentrations were prepared on glass and silicon substrates by magnetron sputtering. The optical properties of ZnO thin films, such as transmittance, reflectivity, surface morphology and microstructure, were studied and analyzed by spectrophotometer, X-ray diffraction (XRD), scanning electron microscope (SEM) and spectrophotometer. The results show that the (101), (110), (103), (201) faces of the molecular structure of the films have the characteristics of preferential growth with the increase of Al doping concentration; The transmittance and reflectivity are blue shifted with the increase of different directions; In the ultraviolet region, the average transmittance of the refractive index is higher, and the effect of refraction is better; In the ultraviolet region, the peak position is higher .At the same time, there is a slight shift in the peak position.

Dielectric properties and crystallite size distribution of modified lead-free sodium-bismuth titanate ceramics

Abstract: Abstract Influence of (K0.5Bi0.5)TiO3 (KBT) dopants on crystal and microstructure, ferroelectric and dielectric properties of ceramic composition from morphotropic phase boundary in the system (1–x–y)(Na0.5Bi0.5)TiO3 – xBaTiO3 – y (K0.5Bi0.5)TiO3 (x = 0.06, y = 0–0.15) additionally modified by ZnO additives was studied using a complex of methods. Changes from 42.8 nm to 62.6 nm of the volume-weighted crystallite size distribution function G(L) corresponding to coherent scattering regions were observed. The microstructure and the second harmonic generation data indicated a change in the relative content of polar nanoregions in tetragonal nonpolar matrix. Decrease in temperatures of phase transitions T m and T d was observed with KBT concentration increasing.

Research on in-situ detection of double-ended clamped beam biosensors

Abstract: Abstract One of the most frequent malignant tumors seen in clinics is primary liver cancer, also referred to as the "king of cancers." Therefore, the necessity for an effective and precise detection technique is urgent. Compared with the cantilever beam, the double-ended clamped beam has the characteristics of higher resonance frequency and stronger noise immunity, so it has a good application prospect as a biosensor. This paper takes the double-ended clamped beam biosensor as the object and focuses on the method that can be applied to the early diagnosis and detection of liver cancer. The manufacturing process of the double-ended clamped beam and the biofunctional modification of the beam surface were introduced. Meantime, this paper introduces the integration of the composite double-ended clamped beam biosensor system. As a result, a high-sensitivity, high-reliability in situ real-time monitoring technology for early-stage liver cancer is proposed. A composite double-ended clamped beam made of silicon and silicon nitride is used. The size of the double-ended clamped beam is 280 µm × 50µm × 5µm. This paper provides a low-cost, portable, and rapid early diagnosis method for liver cancer, which has very significant application value in the field of early cancer screening.

Mechanical and magnetic properties of Mg-Ni hydrosilicate nanoscrolls as study objects for atomic force microscopy

Abstract: In hydrosilicates with the structure of chrysotile, pecoraite, and halloysite, elastic strains in the composite hydrosilicate layer are compensated by folding into nanoscrolls. A wide range of such particles with different compositions can be produced by hydrothermal synthesis, which, together with the structural and morphological characteristics, makes them promising adsorbents, capsules, catalysts, and reinforcing components of composite materials. For such potential applications as magnetically controlled adsorbents and catalysts, ferromagnetic chemical elements are included in the composition of the nanoscrolls. Studies of the individual nanoscrolls require special approaches. This article discusses the use of atomic force microscopy for such studies.

Structural, electronic and optical properties of Li3BN2 under pressure: a first-principles calculation

Abstract: Abstract In this article, by using the first-principles calculations based on density functional theory (DFT), we investigate the structural, electronic and optical properties of α-Li3BN2 under pressure up to 10 GPa. The obtained results indicate that the value of V/V0 basically decreases linearly with the increase of pressure. By increasing the pressure, α-Li3BN2 remains an indirect band gap semi-conductor. Although, the band gap of the α-Li3BN2 increases with pressure. Besides, the optical spectra exhibit anisotropy in the x and z directions and a small blue shift under pressure.

Optimal design of automatic assembly system for bolts and nuts in sets

Abstract: Abstract Due to the slow assembly speed, large consumption of compressed air, and low qualification rate, the automatic assembly system for bolts and nuts in sets needs to be optimized urgently. The performance requirements of the system were analyzed, and the evaluation indexes of the system were proposed. Since the efficiency of the system mainly depends on the pneumatic components, the optimization work focuses on the pneumatic circuit. Parameters of the pneumatic circuit and pipeline were obtained through modeling and simulation. After parameter optimization, prototype test results have shown that the assembly speed and qualification rate of the optimized system is increased by 47.83% and 7.77%, respectively, while the air consumption is reduced by 23.39% compared with the original system.

Equipment partition and control node location method for artificial colored-sand production line

Abstract: Abstract According to the principle of regional centralization and overall decentralization, K-means algorithm based on elbow rule was adopted to divide the equipment on the artificial colored-sand production line into several clustering partitions. The results were optimized to realize power balance between different partitions. Center of gravity method was adopted to determine the location of each control node. The goal of minimizing the total weighted distance from each equipment to its corresponding control node was achieved. Field results have shown that hardware and wiring cost of the production line has decreased by 13.32% and 20.41%, respectively.

Excellent electrochemical performance of all-solid-state planar on-chip micro-supercapacitors with narrow interdigital electrode configuration

Abstract: Abstract As a popular direction of research in micro-energy storage devices, improving the comprehensive performance of all-solid-state planar on-chip micro-supercapacitors (MSCs) has received increasing attention. Graphene quantum dots (GQDs) are a new type of nano-scale electrode materials that can improve the electrochemical performance of devices. In addition, the doping of nitrogen/oxygen heteroatoms can further improve the electrochemical activity of the electrode materials. In this paper, nitrogen-oxygen co-doped graphene quantum dots (NO-GQDs) were used as electrode materials, and a modified liquid-air interface self-assembly method was used to fabricate the electrode films. Finally, the MSCs with narrow interdigital electrode configuration were prepared by photolithography with an electrode width/interdigital gap of 3 μm/1 μm. The prepared MSCs have excellent electrochemical performance, including an area capacitance of 150.63 μF cm−2, an energy density of 20.92 nWh cm−2, a power density of 175.49 μW cm−2, a relaxation time constant of 3.53 μs, and a capacitance retention of 90.42%. As shown by the results, the combination of NO-GQDs and narrow interdigital electrode configuration provides a significant improvement in the comprehensive electrochemical performance of the all-solid-state planar on-chip MSCs.

Conductivity and structural analysis of perovskite-like BiAlO3 doped (K0.44Na0.52Li0.4)(Nb0.86Ta0.1Sb0.04)O3 based perovskites system

Abstract: Abstract In this study, the structural analysis of the samples (1-x)(K0.44Na0.52Li0.04-Nb0.86Ta0.1Sb0.04)-x(BiAlO3) (x = 0, 0.005, 0.007, 0.01, and 0.05) showed that the samples have orthorhombic and tetragonal phases. The effect of increasing concentration of BA in (1-x)(K0.44Na0.52Li0.04-Nb0.86Ta0.1Sb0.04)-x(BiAlO3) samples have been studied on impedance and modulus analysis of the samples in 100 °C–500 °C temperature range. All the samples were found to exhibit NTCR behavior. AC conductivity showed that the conduction increase with increase in temperature. The dielectric and capacitive behavior of the samples were also analyzed from the dielectric and modulus study of the samples.