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Detecting and monitoring hydrogen peroxide (H2O2) levels is crucial across various industries due to its potential health hazards at elevated concentrations. Hence, there's an urgent need for cost-effective, rapid, and straightforward analytical methods for H2O2 detection and monitoring. This study introduces a simple synthesis method for Barium Titanate (BaTiO3) and Molybdenum disulfide (MoS2) (BaTiO3/MS) nanocomposite via mechanochemical means. The nanocomposite exhibits remarkable peroxidase-like activity, catalyzing the oxidation of TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H2O2. This catalytic reaction results in the formation of a blue-colored solution with an absorbance peak at 652 nm. The increase in absorbance, facilitated by the catalytic properties of BaTiO3/MS enables precise detection of H2O2 with a detection limit of 8.0 µM. Furthermore, a modified filter paper incorporating the nanocomposite and agarose gel with TMB was developed. The change in color intensity of the filter paper upon exposure to H2O2 was observed and quantified in terms of RGB (Red Green Blue) values using an Android smartphone-based software Color Meter as well as Windows-based software ImageJ. Both the programs gave nearly similar RGB values. This paper-based sensor eliminates the reliance on a UV-visible spectrophotometer, making it portable and user-friendly. This study presents a novel approach for optical and colorimetric detection, with the potential to advance sensing devices for various analytes. [ABSTRACT FROM AUTHOR]

The small‐signal dielectric and piezoelectric coefficients of paper‐derived sodium potassium niobate, K0.5Na0.5NbO3 (KNN), were compared with those of conventionally prepared samples. Results show similar functional properties of paper‐derived KNN without significantly decreasing the small‐signal piezoelectric coefficient. The structure and microstructure analysis of conventional KNN and paper‐derived KNN did not reveal any significant difference in the crystal structure and grain size. However, the temperature‐dependent inter‐ferroelectric phase transition temperature estimated from the temperature‐dependent dielectric permittivity data revealed a decrease of approximately 18°C for the paper‐derived KNN and is possibly associated with the structural and microstructural defects. This work indicates that optimizing suspension chemistry and sintering conditions will be critical to enhance the functional response of paper‐derived KNN further. Moreover, paper‐derived ceramic processing, a novel and cost‐effective additive manufacturing technology, can be potentially used to fabricate other electroceramics with a wide range of porosities and sizes as well as complex geometries and multilayer structures. [ABSTRACT FROM AUTHOR]

Detecting and monitoring hydrogen peroxide (H2O2) levels is crucial across various industries due to its potential health hazards at elevated concentrations. Hence, there's an urgent need for cost-effective, rapid, and straightforward analytical methods for H2O2 detection and monitoring. This study introduces a simple synthesis method for Barium Titanate (BaTiO3) and Molybdenum disulfide (MoS2) (BaTiO3/MS) nanocomposite via mechanochemical means. The nanocomposite exhibits remarkable peroxidase-like activity, catalyzing the oxidation of TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H2O2. This catalytic reaction results in the formation of a blue-colored solution with an absorbance peak at 652 nm. The increase in absorbance, facilitated by the catalytic properties of BaTiO3/MS enables precise detection of H2O2 with a detection limit of 8.0 µM. Furthermore, a modified filter paper incorporating the nanocomposite and agarose gel with TMB was developed. The change in color intensity of the filter paper upon exposure to H2O2 was observed and quantified in terms of RGB (Red Green Blue) values using an Android smartphone-based software Color Meter as well as Windows-based software ImageJ. Both the programs gave nearly similar RGB values. This paper-based sensor eliminates the reliance on a UV-visible spectrophotometer, making it portable and user-friendly. This study presents a novel approach for optical and colorimetric detection, with the potential to advance sensing devices for various analytes. [ABSTRACT FROM AUTHOR]

A piezoelectric paper based on BaTiO3 (BTO) nanoparticles and bacterial cellulose (BC) with excellent output properties for application of nanogenerators (NGs) is reported. A facile and scalable vacuum filtration method is used to fabricate the piezoelectric paper. The BTO/BC piezoelectric paper based NG shows outstanding output performance with open‐circuit voltage of 14 V and short‐circuit current density of 190 nA cm−2. The maximum power density generated by this unique BTO/BC structure is more than ten times higher than BTO/polydimethylsiloxane structure. In bending conditions, the NG device can generate output voltage of 1.5 V, which is capable of driving a liquid crystal display screen. The improved performance can be ascribed to homogeneous distribution of piezoelectric BTO nanoparticles in the BC matrix as well as the enhanced stress on piezoelectric nanoparticles implemented by the unique percolated networks of BC nanofibers. The flexible BTO/BC piezoelectric paper based NG is lightweight, eco‐friendly, and cost‐effective, which holds great promises for achieving wearable or implantable energy harvesters and self‐powered electronics. [ABSTRACT FROM AUTHOR]

Flexible piezoelectric sensors with short response time and high sensitivity have broad applications in micro pressure sensing and human motion monitoring. However, the common piezoelectric materials are not conducive to improving the piezoelectric output performance due to the limited specific surface area. In this work, flower-like BaTiO 3 particles with a large specific surface area were synthesized and combined with PVDF to construct piezoelectric sensor with porous structure for further improving the output voltage. The designed piezoelectric sensor (BPP-PC) has a sensitivity of 0.13 V/kPa, a pressure range of 0–20 kPa, and a response time of 78 ms. Meanwhile, the sensor covered with flexible hydrophobic film illustrates an excellent detection ability for water drops of 0.1 g. The human motion of foot stamping, hand patting, wrist and finger bending can also be sensitively detected. Therefore, the BPP-PC sensors can be used for detecting tiny pressure and monitoring human motion in the future. [Display omitted] • Piezoelectric sensor with porous structure is prepared by scraping 3D BT particles/PVDF. • At least 0.1 mg external micro pressure can be sensed. • Super-flexible hydrophobic film ensures normal fork electrodes with minimal impact on micro force detection. • Sensor has a sensitivity of 0.13 V/kPa, a pressure range of 0–20 kPa, and a response time of 78 ms. [ABSTRACT FROM AUTHOR]

Reversible cross‐linked structures are widely used to turn thermoset plastics into recyclable and self‐healing vitrimer materials, but seldom applied in traditional flexible rubber/ceramic composites. In this paper, dioxaborolanes based flexible poly (isoprene (IP)‐co‐acrylonitrile (AN)) vitrimer is synthesized as the rubber matrix by copolymerizing with functional monomers at 5°C for 7 h, and mixed with 5 wt% modified barium titanates (BT) to prepare flexible high dielectric vitrimer composite. The materials are characterized by FTIR, TGA, SEM, DMA, etc. The results indicate that reversible crosslinking can occur above 76.4°C, and copolymerizing with the dioxaborolanes based monomers can turn poly (IP‐co‐AN) into the flexible vitrimer. The poly (IP‐co‐AN)/BT vitrimer composite not only shows a good thermal stability below 145.6°C, but also exhibits an excellent particle dispersivity and a certain self‐healing function at 80°C. The poly (IP‐co‐AN)/BT vitrimer composite has a storage modulus E' about 3.18 MPa at 25°C and Tg about −5.4°C, and shows a higher relative permittivity about 7.5 and lower dielectric loss about 0.156 at 1 k Hz. The results indicate that this paper provides a new method to achieve multifunction and high dielectricity for composites. Highlight: Reversible cross‐linked structures are applied in rubber / ceramic compositesCross‐linked flexible composites are reprocessable and self‐healingReversible bonds between particles and matrix improve compatibilitySynergism of BaTiO3 and cross‐linked structure enhances dielectric properties [ABSTRACT FROM AUTHOR]

Key solutions for material selection, processing, and performance of environmentally friendly high‐power generators are addressed. High voltage and high power generation of flexible devices using piezoelectric Bi0.5(Na0.78K0.22)TiO3 nanoparticle filler–polydimethylsiloxane (PDMS) elastomeric matrix for a lead‐free piezoelectric composite film on a cellulose paper substrate is demonstrated. To elucidate the principle of power generation by the piezoelectric composite configuration, the dielectric and piezoelectric characteristics of the composite film are investigated and the results are compared with those of theoretical modeling. The paper‐based composite generator produces a large output voltage of ≈100 V and an average current of ≈20 µA (max. ≈30 µA) through tapping stimulation, which is a record‐high performance compared to previously reported flexible lead‐free piezoelectric composite energy harvesters. Moreover, a triboelectric‐hybridized piezoelectric composite device using a micro‐patterned PDMS shows a much higher output voltage of ≈250 V and output power of ≈0.5 mW, which drives 300 light‐emitting diodes. These results prove that a new class of paper‐based and lead‐free energy harvesting device provides a strong possibility for enlarging the functionality and the capability of high‐power scavengers in flexible and wearable electronics such as sensors and medical devices. [ABSTRACT FROM AUTHOR]

In this paper, based on the developed statistical-thermodynamic model, which is based on data on the local structure of the compound and taking into account the striction interaction caused by the large sizes of the Ba and K cations, the formation of ferroelectric phases in BaTiO3 and KNbO3 perovskites has been studied. Based on the modified eight-minimum model, it has been possible to qualitatively identify the factors that determine the features of the thermodynamic behavior of these crystals and to reproduce the process of formation of the whole set of phase states observed in BaTiO3 and KNbO3. [ABSTRACT FROM AUTHOR]

Because of the ever-growing world population and the burgeoning of economic advancements, solving both environmental and energy-driven challenges are of prime concern. In the view of the current scenario, photocatalyst as an environmentally friendly method has rapidly emerged due to its prominent function in the conversion of solar energy for overcoming two aforementioned serious challenges. Recently, numerous attempts have been carried out for enhancing the visible-light photoactivity by application of TiO2 as photocatalyst because of its extensive scope of employment in both environmental-related and energy regions. Nevertheless, the photocatalytic performance of TiO2 under visible-light illumination is seriously restricted by the absorption edge in the ultra-violet range and the rapid electron–hole recombination. Extensive research has been dedicated to bypassing the shortcomings of titanium dioxide and hence improving its photoactivity under visible light. To be more specific, some approaches for modification of TiO2 properties include tetragonal BaTiO3 nanoparticles, ultrasound-assisted preparation of rGO/TiO2 nanocomposite, BaTiO3/ZnO heterostructured photocatalyst, Sol pH-induced ZnO-TiO2 multi-phase composite, BaTiO3/g-C3N4 heterojunction, TiO2-zeolite nanocomposite, etc., were explored and developed. Moreover, in this review paper, the authors briefly evaluated various nano-TiO2 synthesis methods, such as sol-gel, hydrothermal, solvothermal, and mixed ones. Despite the excellent achievements and the improvements in this area, the probability of nano-TiO2 modification for highly efficacious photocatalyst systems has not been completely explored and its commercialisation still is problematic. As a result, still, intensive research efforts require to effectively overcome those challenges for reaching a bright future in the wastewater treatment process with minimum environmental adverse effects. [ABSTRACT FROM AUTHOR]

In this paper, the performances of a wavelength interrogation-based optical fiber surface plasmon resonance sensor for hemoglobin (Hb) concentration is investigated by theoretical simulation. The proposed configuration incorporates optical fiber, 70 nm silver, 18 nm barium titanate (BaTiO3), and 2 nm zinc oxide. Simulation results show the sensor exhibits refractive index sensitivity of 4023 nm/RIU and concentration sensitivity of 10.0873 nm/(gꞏdL), along with Hb concentration varying from 0 to 14 g/dL. This paper especially focuses on the influence of BaTiO3 on the performances of the proposed sensor with light wavelength ranging from 350 to 1000 nm. Comparison analysis indicates sandwiching 18 nm BaTiO3 between sensing layers not only enhances the concentration sensitivity by 30.14% but also decreases the nonlinear error of the sensor from 0.68% to 0.63%. For a wavelength accuracy of 0.1 nm, the proposed sensor can provide a resolution of 0.0099 g/dL for Hb concentration detection. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the intrinsic mechanical contributions of poled piezoelectric ceramics under the three ferroelectric phases [tetragonal (4 mm), rhombohedral (3 m) and orthorhombic (mm2)]. The intrinsic elastic coefficients and spontaneous strains of saturated and unsaturated poling piezoelectric ceramics are analyzed and calculated by probability density functions of orientation (PDFOs) and Reuss or Voigt average, and the analytical results of the intrinsic mechanical properties of piezoelectric ceramics with the poling degree are obtained. In addition, this paper also calculates the Young's modulus and shear modulus of barium titanate (BaTiO3) piezoelectric ceramics by PDFO which are based on the Reuss, Voigt and Hill averages. Comparing them with the published theoretical calculation data shows that the results calculated by the finite element method under the saturated and unsaturated poling states are within the range of the results calculated by us using the three average theories through PDFO, and it shows the accuracy of calculation by PDFO. [ABSTRACT FROM AUTHOR]

Tunnel field effect transistor (TFET) is a gate-controlled, quantum FET device, exhibiting band-to-band tunneling (BTBT) transport phenomena with lower subthreshold swing (SS) than bulk MOSFET devices. Low ON-state current (ION) is an inherent problem with TFET devices. Various research groups are working to address the limitations due to low ON-state current and for performance improvement of the device. The work in this paper is an attempt to overcome the low switching current issue by using ferroelectric material (Fe), barium titanate (BaTiO3) in conventional double gate TFET, having Si1-xGex/Si semiconductors configuration. In the proposed TFET device, the high-κ dielectric HfO2 is replaced by BaTiO3, ferroelectric material (Fe) in the source region. The replacement of HfO2 gate materials by BaTiO3 Fe is found to improve ION (~ order of 10−8 A/µm -to-10−5 A/µm). The FeDGTFET device shows ~ 103 times improvement in ION with unaffected IOFF (~ 10−20 A/µm). In circuit and system design figure of merit, optimization is a critical task for designers. The work in this paper is divided into three sections. Initially, two structures based on high-κ, one with only high-κ (HfO2) DGTFET and the other one based on HfO2 and ferroelectric material BaTiO3 (FeDGTFET), are compared. Analysis of the electric parameters of the two structures shows the performance advantage of the structure based on the ferroelectric material. Next, a parametric study of the FeDGTFET structure is performed linking Silvaco Atlas with MATLAB to analyze the electrical parameters of FeDGTFET. Finally, an optimization technique called algorithm genetic 'AG' is employed to show enhancement in the ION current from 10−5 to 10−4A/µm without affecting the IOFF. [ABSTRACT FROM AUTHOR]

The particle size of powder coatings is an important factor affecting flow and fluidization performance, which in turn determines the quality of the coating. Powder coating particles, such as boron nitride, titanium dioxide, barium titanate, niobium oxide, and tungsten oxide, can be seen in SEM images as circular or polygonal shapes, with irregular edges and sizes, as well as aggregation and stacking between them. This paper introduces a novel method of automatic particle identification and size analysis applied in SEM images for the investigation of coating quality. Firstly, a fast gradient segmentation algorithm (Split–Merge) is utilized to automatically generate samples through determining the adhesive particles and particle groups. The samples are then manually checked and corrected to further segment the particles in order to form the dataset. Finally, the YOLOv5, a mature target detection algorithm, is used to train the labeled data in order to produce a multi-target detection recognition model. The model can be applied to identify more pictures of the same substance, and the particles' long and short axes are estimated using the elliptical coverage of the particles within the identified image boundary box. Experiment results from four kinds of powders suggest that this method can provide automatic particle size analysis for industrial SEM particle images. [ABSTRACT FROM AUTHOR]

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This paper shows the results of experimental studies of the influence of oxygen pressure under pulsed laser deposition on the electrophysical parameters of BaTiO3 nanocrystalline films. The elemental composition of BaTiO3 films obtained at different pressures (1×10−5 Torr (vacuum) and 1×10−2 Torr (oxygen)) was studied by XPS methods. Based on the obtained results, the energy-efficient memristor structures based on BaTiO3 nanocrystalline films were proposed. It was found that 20-nm-thick BaTiO3 films based memristive structure exhibited stable resistive switching effect: HRL/LRS∼10 for 100000 cycles. The results obtained can be used to fabricate energy-efficient memristive structures. [ABSTRACT FROM AUTHOR]

In this paper, we propose an optimized device structure with a highly stable process that addresses threshold voltage shift issues in the String-Select-Line (SSL) and Ground-Select-Line (GSL) gates using ferroelectric memory in 3D NAND flash memory applications. The proposed device utilizes nickel (Ni) instead of tungsten (W) for the GSL and SSL gates, enabling optimized polarization properties during the annealing process and leveraging the disparity in thermal expansion coefficients. Notably, the difference in thermal expansion coefficient from tungsten (W), employed in other Word Line (WL) gates, allows effective control over polarization properties. To validate the proposed structure, we fabricated and measured a Metal–Ferroelectric–Insulator–Silicon (MFIS) capacitor utilizing Hafnium–Zirconium Oxide (HZO) material. The measurement results indicate that a change in the upper metal layer results in a more than fivefold increase in the variance of polarization characteristics between the WL gates (responsible for the memory function) and the SSL and GSL gates dedicated to channel control. In addition, process simulation was conducted using the same device structure, confirming the application of tensile stress to the HZO thin film in the case of a W electrode and compressive stress in the case of a Ni electrode. Furthermore, applying this controlled polarization characteristic parameter to the 3D NAND flash memory structure revealed a reduction in the threshold voltage shift of the control gate from a previous change of 2.6 V or more to 0.05 V, facilitating stable control. [ABSTRACT FROM AUTHOR]

Understanding space charge dynamics in cross-linked polyethylene (XLPE) is crucial for optimizing electrical insulation systems, preventing insulation failure, and ensuring the reliable performance of electrical equipment. Research is focused on advanced characterization techniques and predictive models to mitigate space charge effects, which are key factors in the aging and degradation of high-voltage polymer insulators. While experimental measurements are common, theoretical models are less so. This paper investigates the dynamics of space charges in barium titanate (BaTiO3)-doped XLPE nanocomposites under a continuous electric field using the bipolar charge transport model. The results show that doping with BaTiO3 significantly improves the dielectric properties of XLPE. The study presents and discusses the evolution of the electric field and charge density over time for different types of charges. [ABSTRACT FROM AUTHOR]

Barium-titanium-peroxo type amorphous materials gained importance with the advent of wet-chemical methods for the production of crystalline perovskite barium titanate (BaTiO 3) electroceramics. In this paper, the chemical nature of the barium-titanium-peroxo precursor was determined by means of elemental (EPMA), spectroscopic (FT-IR and FT-Raman), XRD and thermal (DSC and TGA/DTA) analyses. Several synthesis parameters such as the barium source, the peroxide treatment time, the reaction temperature and the reaction time were investigated. The precursor was also thermally treated at varying temperatures between 30 °C and 1000 °C. Relatively high reaction temperatures are detrimental to the Ba∙O∙Ti structure, resulting in plain TiO 2 formation. Though relatively low temperatures (ice bath) are needed to suppress unwanted TiOCl 2 , ambient synthesis conditions and short reaction time (2 h) resulted in the desired single-source properties, i.e. amorphous Ba∙O∙Ti-peroxo structure with Ba/Ti ratio of unity (1.04 ± 0.04). The addition of an extra stirring step during H 2 O 2 addition lowered the chance of carbonate incorporation in the precursor. Thermal analysis under air and nitrogen atmosphere was performed and a stoichiometric formula of Ba 2,08 Ti 2 O(O 2) 1,9 (OH) 5,3 ∙3,1H 2 O was calculated, which was in very good agreement with literature data. The barium-titanium-peroxo-hydroxide material proved to be an excellent single-source precursor. Phase-pure, highly crystalline and facetted, stoichiometric BaTiO 3 particles with differently crystallographically oriented facets were obtained via the molten-salt solid-state method ({100} or {111} oriented facets) as well as the hydrothermal route ({100} oriented facets). [ABSTRACT FROM AUTHOR]

Barium titanate is a ferroelectric material used as a dielectric in thin film capacitors owing to its high dielectric constant. Barrier layers are utilized in these capacitors to improve the capacitors' performance by controlling the microstructure and creating thin resistive films. In this paper, the effect of barrier layers in Pt/BT/Pt capacitors is studied using zinc oxide and aluminium oxide. The performance parameters such as capacitance density, leakage current, equivalent series resistance, dielectric loss and dielectric strength of Pt/BT/Pt thin film capacitors with barrier layers of different sizes are simulated using COMSOL Multiphysics modeling software. 2 nm thick aluminum oxide as Pt ‐ BT barrier layer gives optimal performance. The leakage current, dielectric loss, capacitance density, equivalent series resistance and dielectric strength of Pt/BT/Pt capacitor are found to be 0.519 mA, 9.62×10−12, 172.8 fF/μm2, 9.62 kΩ, 108 V/m respectively whereas that of Pt/ALO/BT/ALO/Pt capacitor are found to be 1.56×10−18 A, 7.81×10−18, 11.6 fF/μm2, 9.01×1015 Ω, 5.05×109 V/m respectively. The low capacitance in Pt/ALO/BT/ALO/Pt capacitor is due to the low dielectric constant of aluminium dioxide barrier layer. The reduced leakage current and increased equivalent series resistance is due to the low conductivity of the aluminium oxide barrier layer. The use of aluminium oxide barrier layer between the conductive surfaces can reduce the electric field and increase the breakdown voltage, leading to improved dielectric strength and reduced dielectric loss. [ABSTRACT FROM AUTHOR]

A nanogenerator (NG) is an energy harvester device that converts mechanical energy into electrical energy on a small scale by relying on physical changes. Piezoelectric semiconductor materials play a key role in producing high output power in piezoelectric nanogenerator. Low cost, reliability, deformation, and electrical and thermal properties are the main criteria for an excellent device. Typically, there are several main types of piezoelectric materials, zinc oxide (ZnO) nanorods, barium titanate (BaTiO3) and lead zirconate titanate (PZT). Among those candidate, ZnO nanorods have shown high performance features due to their unique characteristics, such as having a wide-bandgap semiconductor energy of 3.3 eV and the ability to produce more ordered and uniform structures. In addition, ZnO nanorods have generated considerable output power, mainly due to their elastic nanostructure, mechanical stability and appropriate bandgap. Apart from that, doping the ZnO nanorods and adding doping impurities into the bulk ZnO nanorods are shown to have an influence on device performance. Based on findings, Ni-doped ZnO nanorods are found to have higher output power and surface area compared to other doped. This paper discusses several techniques for the synthesis growth of ZnO nanorods. Findings show that the hydrothermal method is the most commonly used technique due to its low cost and straightforward process. This paper reveals that the growth of ZnO nanorods using the hydrothermal method has achieved a high power density of 9 µWcm−2. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study and to model the dielectric behavior of two ternary composites prepared from a mixture of barium titanate (BaTiO3) and one of the two materials (iron oxide (Fe304) or ferrite) in epoxy resin matrix which the volume fraction is fixed at 70%. The time domain spectroscopy (TDS) method is used to characterize the samples under test in the range from direct current (DC) to 12.5 GHz. The conductivity behavior study is performed at a low frequency of 250 MHz, throughout this work. The study has therefore been focused on the effect of adding iron oxide and ferrite to titanate included in an epoxy matrix. In this work, we present a new approach to model the permittivity behavior of a ternary composite by the introduction of the shape factor for different mixture laws in order to best fit the model to experimental data. Subsequently, a comparison is made with these modified laws to determine the most suitable one. To predict the dielectric permittivities of the ternary composites and their shape factor coefficients in a quantitative manner, we use a numerical optimization method for identification the parameters of the theoretical model. These composite materials find their interest in the miniaturization of electronic components used in microelectronic circuits and in the telecommunication applications. [ABSTRACT FROM AUTHOR]

In this paper, free vibration analysis and temperature-dependent buckling behavior of porous functionally graded magneto-electro-thermo-elastic material consisting of cobalt ferrite and barium titanate were modeled and analyzed. A high-order sinusoidal shear deformation theory was used to accurately model the anisotropic material behavior. The study examined the porosity role variation across thickness in the buckling and free vibration behavior of nanobeams, as well as the effects of magneto-electro-elastic coupling, thermal stresses, nonlocal properties, externally applied electric and magnetic field potential, and porosity volume fraction. [ABSTRACT FROM AUTHOR]

This paper investigates the possibilities of limiting emergency short current pulses by using materials with a positive temperature coefficient. A computational model and method for simulating this process were proposed. Barium titanate was considered a promising material for current-limiting devices due to its low cost, ease of manufacturing and autonomy. The current-limiting properties of a PTC thermistor device were estimated in relation to a significant pulse current overload (10 ms). The value of taking into account the varistor effect when modeling energy dissipation by a PTC thermistor is experimentally demonstrated. The results of the experiment were used in the development of computer models of the current-limiting properties of PTC thermistors. A method for taking into account the varistor effect in the developed models is proposed. It is noted that in order to increase the accuracy of the calculation, it is important to take into account the heat transfer between the PTC thermistor and its contact system. It is also shown that this heat transfer is capable of creating a significant longitudinal temperature gradient inside the PTC thermistor, which creates a high level of thermal stress and leads to mechanical failure. Destruction of this type has been observed during experiments. This research was carried out within the state assignment FSEG-2023-0012. [ABSTRACT FROM AUTHOR]

This paper focuses on the cavity perturbation technique to measure the dielectric properties of nanoparticles: (i) cobalt ferrite (ii) barium titanate and (iii) core-shell cobalt ferrite-barium titanate. The shift in TE103 and TE105 resonant mode is compared for the above three nanomaterials which in turn is correlated to its dielectric properties. Barium titanate has the highest shift in resonance peak and it is directly proportional to its relative permittivity followed by cobalt ferrite-barium titanate and cobalt ferrite respectively. However, the half power bandwidth, Δ f is highest for the cobalt ferrite nanoparticles and least for barium titanate. Approximately 1.145 MHz shift and 3.391 MHz shift is observed for the insertion of the lossy core-shell cobalt ferrite in TE103 and TE105 modes. The quality factor for barium titante was measured to be approximately twice to that of cobalt ferrite for this particular experiment. [ABSTRACT FROM AUTHOR]

Purpose: The present paper focuses on the propagation behaviour of Shear Horizontal (SH) waves in a fluid-saturated functionally graded fractured porous material layer consisting of sedimentary rocks perfectly bonded to an irregular piezoelectric semi-infinite substrate with flexoelectric effect. Two distinct cases corresponding to two differently shaped irregularities, viz. rectangular and parabolic, are considered at the layer-substrate interface. Methods: With the help of Fourier transform, inverse Fourier transform, and perturbation technique, complex frequency relation has been derived for each type of irregular interface. Two different flexoelectric materials, viz. Lithium niobate (LiNbO 3) and Barium titanate (BaTiO 3) , are taken into account for performing comparative graphical analysis. Results: Obtained frequency relations are dissociated into real and imaginary components representing the dispersion and damping of SH-wave propagation. Dispersion and attenuation characteristics of SH-waves are executed graphically on the basis of several key parameters, such as irregularity, functional gradient, flexoelectric coefficient, volume fraction of matrix and fracture pores, piezoelectric, and dielectric constants. Conclusions: On applying the referred conditions, the dispersion equations for both type of irregularities fairly match with the Classical Love wave equation. This fact validates the consideration of the layered composite structures. The noteworthy effects of the key parameters on the dispersion and damping of SH-waves are revealed graphically. Moreover, the phase and damped velocities of SH-waves are observed to be significantly greater for LiNbO 3 than for BaTiO 3 in each irregular case. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis bacteria is an illness that affects many people worldwide. Early diagnosis is crucial for patient care and can lower the death rate. As a result, sensitive and rapid detection of mycobacterium tuberculosis bacteria in the blood is crucial. In this paper, a novel surface plasmon resonance (SPRE) sensor consisting of a coupling prism, silver (Ag), barium titanate (BaTiO3) and graphene (Gr) layers is presented. The transfer matrix (TM) technique is used for the analysis of the SPRE structure. The Ag and BaTiO3 thicknesses and the number of Gr sheets are optimized to get the highest sensitivity of the proposed SPRE biosensor. The full width at half maximum (FWHM), detection accuracy (DA) and figure of merit (FOM) are investigated. The best performance has been obtained with 65 nm (Ag), and 9 nm (BaTiO3). The number of Gr layers is investigated and optimized to two layers. The highest sensitivity of 300 deg./RIU has been obtained for the proposed SPRE biosensor when the optimized thicknesses are employed. Compared with existing SPRE biosensors in the literature, the proposed sensor exhibits greater sensitivity. The excellent performance makes this SPRE-based sensor promising to be used in numerous biosensing applications. [ABSTRACT FROM AUTHOR]

AbstractThis paper highlighted in preparation and their properties of Y3+ doped barium titanate (BaTiO3) nanocrystals using inverse miniemulsion. The yttrium (Y) element dopant as the earlier utilized rare earth was used for barium titanate (BaTiO3) modification. The cubic structure of Y3+ doped BaTiO3 nanocrystals were successfully incubated in stable droplets of inverse miniemulsion under the solvent-thermal treatment condition. The suitable Y3+ doping amount in nanocrystals had positively attributed to reduce the value of bandgap (Eg), to prolong the fluorescence lifetime, and to improve the photoelectric properties. The photodegradation mechanism and the schematic diagram of fluorescence emission and radical production were suggested for explanation the relation between photoelectric characteristics and photocatalytic properties. The selected 1.0% Y3+ doped nanocrystal provided an excellent photocatalysis candidate for organic compound photodegradation. [ABSTRACT FROM AUTHOR]

The structural, microstructural, dielectric, optical, ferroelectric, and magnetic properties of cobalt doped barium calcium titanate (BCT) (Ba 0.80 Ca 0.20 Ti 1-x Co x O 3 with x = 0.000, 0.005, 0.010, 0.015, and 0.020) ceramics have been reported in this paper. The ceramic samples were prepared by the conventional solid-state reaction method. For all of the prepared samples, the tetragonal structure with the space group P 4 mm has been confirmed using the refinement method through Rietveld refinement of X-ray diffraction patterns. Field Emission Scanning Electron Microscopy (FESEM) micrographs revealed that the average particle size exists in micrometre range (0.3–0.8) μm. Optical studies revealed a gradual decrease in the energy bandgap from 3.31 eV to 2.71 eV with increasing doping concentration. A decreasing trend was observed in the dielectric characteristics of the material with changing frequencies at room temperature. Ferroelectric (P-E loops) analysis displayed an increase in both remnant polarization and maximum polarization of the ceramic with the increasing applied electric field. The highest value for the energy storage efficiency (η) was calculated to be 20.51 %. Magnetic analysis conducted at room temperature revealed the enhancement in ferromagnetism with the increase in doping concentration. [ABSTRACT FROM AUTHOR]

Barium titanate (BTO) is well-known (as a photo- or sono/piezo-catalyst) to produce hydrogen peroxide via 2-electron reduction of oxygen in the presence of a sacrificial quencher, such as isopropanol. While barium titanate nanoparticles with a tetragonal crystal structure (piezoelectric) are particularly reactive, the recovery and reuse of these nano-catalysts from reactions can be difficult. Here, barium titanate nanoparticles of typically 200 nm to 600 nm diameter are embedded into a host film of a polymer of intrinsic microporosity (PIM-EA-TB). Due to molecular rigidity of the polymer, there is no capping effect, and the surface catalytic reaction occurs effectively with a catalyst embedded in the polymer. In this exploratory work, the catalytic formation of H2O2 in the presence of isopropanol is investigated via kinetic studies and by electron paramagnetic resonance (EPR). Perhaps surprisingly, at a neutral pH the rate of the catalytic reaction is substantially increased when barium titanate is embedded into the polymer host and when the polymer is protonated. This is attributed here to a "kinetic cage effect" which exploits the tertiary amine in the polymer backbone with anodic and cathodic processes coupled into a pH neutral reaction. [ABSTRACT FROM AUTHOR]

Measurement of laboratory atomic pair distribution function data has improved with contemporary X‐ray sources, optics and detectors, with acquisition times of the order of minutes for ideal samples. This paper examines resolution effects in pair distribution function data obtained using a convergent‐beam configuration and an Ag X‐ray tube from standard silicon powder and from 10 nm BaTiO3 nanocubes. The elliptical multilayer X‐ray mirror reflects a non‐trivial X‐ray spectrum and introduces resolution effects not commonly treated in ordinary parafocusing divergent‐beam laboratory diffraction. These resolution effects are modeled using the fundamental parameters approach, and the influence this has on interpretation and modeling of the resulting reduced atomic pair distribution function data is demonstrated. [ABSTRACT FROM AUTHOR]

Electrocaloric refrigeration shows the merits of environmental safeguarding, large efficiency, easy combination, and miniaturization as a novel solid-state refrigeration technique. In this paper, Sn4+ is doped into the B site of BLNT ceramics. By adjusting the doping content, the T-C phase transition peak was successfully shifted to room temperature and promoted the formation of relaxor ferroelectrics, resulting in a wider operating temperature range (T span) and improved adiabatic temperature change (ΔT). A comprehensive study was conducted on the crystal structure, surface morphology, dielectric properties, ferroelectricity, and electrical properties of BLNTS ceramics with varying levels of Sn4+ doping. Wherein, when the doping amount is 5Sn, a maximum adiabatic temperature change value (ΔT max) of 1.14 K was obtained, and the temperature span (T span) reached 45 °C (T span is defined as ΔT ≥ 80 % ΔT max). This work proposes a high-performance environmentally friendly electrocaloric effect (ECE) material suitable for solid-state cooling applications. [ABSTRACT FROM AUTHOR]

In the present work, pure and bismuth-doped barium titanates have been prepared using the sol-gel method. The chemical formula used for the synthesis of bi-doped barium titanate is Ba1-xBixTiO3, where the values of x have been chosen to be 0.00, 0.05, 0.075, 0.10, and 0.15. Barium acetate [Ba(CH3COO)2] and titanium (IV) isopropoxide [Ti{OCH(CH3)2}4] have been used as barium and titanium precursors, respectively. For bismuth doping, bismuth (III) nitrate pentahydrate [Bi(NO3)3)5H2O] has been used. The paper discusses the preparation mechanism, tolerance factor, and the thermal characterization (TGA/DSC) results of pure and bi-doped barium titanate ceramics. [ABSTRACT FROM AUTHOR]

This paper presents an application of Legendre polynomial approach to solve the wave propagation in a piezoelectric ZnO planar resonator subjected to stress-free boundary conditions and excited using two thin electrodes connected to an electrical source. The method is able to take into account the boundary conditions, the presence of electrical source and the different dissimilarities of the physical properties. Resonance frequencies of longitudinal modes are calculated in case of an open and short-circuit brunch. Dispersion characteristics are also calculated such as mechanical displacement and stress profiles for different resonance frequencies. The electromechanical coupling coefficient is also calculated. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, microstructure and electrical properties of a new Ba4SrBiTi3Nb7O30 ceramic. X-ray diffraction analysis shows that the sample crystallizes into tungsten bronze structure, and the space group is P4bm. The electrical measurement results show that Ba4SrBiTi3Nb7O30 exhibits good dielectric and ferroelectric properties. The temperature-dependent dielectric permittivity indicates that the transition temperature of the prepared Ba4SrBiTi3Nb7O30 sample is around Tm ≈ 250K. With increasing the frequency, the dielectric peak moves to a lower temperature. Below 250 K, obvious polarization current can be detected, corresponding to the formation of spontaneous ferroelectric polarization. These results indicate the relaxor ferroelectric behavior of Ba4SrBiTi3Nb7O30 ceramic. [ABSTRACT FROM AUTHOR]

Flash sintering was first reported in 2010 by a research group of Raj et al. at Colorado University. Since then, flash sintering has attracted attention as an innovative sintering method that uses the steep power spike, generated when ceramic green compact is heated while an electric field, is applied to densify ceramic green compact in an instant. However, there are several technical challenges that must be overcome before flash sintering can be used as a practical sintering method. This paper outlines the problems and improvements related to flash sintering from a viewpoint of sintering method and introduces the improved flash sintering noted as shrinkage-rate controlled flash sintering developed by the author. [ABSTRACT FROM AUTHOR]