2O3 Composites Research Articles

Impact of Nano CoFe1.75Er0.25O4 Loading Ratios on the Dielectric and Radiation Shielding Properties of Polyvinyl Chloride Polymer

Our research described in this paper was aimed to modify the dielectric and radiation shielding characteristics of polyvinyl chloride (PVC)/x wt % CoFe1.75Er0.25O4 (CFEO) composites to be used in modern applications. PVC polymer loaded with nano CFEO were fabricated by a casting process. The structural and morphological attributes of PVC/x wt % CoFe1.75Er0.25O4 composites were evaluated utilizing X-ray diffraction and scanning electron microscopy techniques. The dielectric characteristics were evaluated via an Inductance, L, Capacitance, C, and Resistance, R (LCR) meter bridge. The dielectric constant and ac conductivity of PVC exhibited a maximum value when it was doped with 1 wt % CFEO. The energy density of the PVC polymer exhibited an irregular drop after being doped with various ratio amounts of CFEO. The radiation shielding aspects were investigated applying the Phy-X/Photon Shielding and Dosimetry (PSD) software. All samples exhibited relatively elevated mass-attenuation coefficient (MAC) values: x = 0 (10.45 cm2/g), x = 0.5 (12.2 cm2/g), x = 1 (13.88 cm2/g), x = 2 (17.07 cm2/g), and x = 3 (20.05 cm2/g) at lower energies, specifically 15 keV, signifying a pronounced photoelectric effect. The MAC rose from 0.0898 cm2/g (x = 0) to 0.0918 cm2/g (x = 5) as the energy rose to 0.5 MeV. The linear attenuation coefficient (LAC) values at 15 keV for all composites exhibit a notable rise with elevated concentrations of CFEO doping: 14.63, 17.35, 20.07, 25.45, and 30.80 cm−1 for samples with x = 0, 0.5, 1, 2, and 3 wt%, respectively. At 15 keV, the mean-free path (MFP) values for samples with x = 0, 0.5, 1, 2, and 3 wt % were approximately 0.068, 0.058, 0.049, 0.039, and 0.033 cm, respectively. At 1 MeV, the MFP value for the same samples increased to 10.934, 10.774, 10.618, 10.318 and 10.035 cm, respectively. The effects of doping amount on the Exposure Buildup Factor (EBF) and the Energy Absorption Buildup Factor (EABF) were also explored.

Non-Stoichiometric BaxMn0.7Cu0.3O3 Perovskites as Catalysts for CO Oxidation: Optimizing the Ba Content

In this work, a series of BaxMn0.7Cu0.3O3 samples (x: 1, 0.9, 0.8, and 0.7, BxMC) was synthesized, characterized, and used as catalysts for CO oxidation reaction. All formulations were active for CO oxidation in the tested conditions. A correlation between the electrical conductivity, obtained by impedance spectroscopy, and the reducibility of the samples, obtained by H2-TPR, was observed. The Ba0.8Mn0.7Cu0.3O3 composition (B0.8MC) showed the best catalytic performance (comparable to that of the 1% Pt/Al2O3 reference sample) during tests conducted under conditions similar to those found in the exhaust gases of current gasoline engines. The characterization data suggest the simultaneous presence of a high Mn(IV)/Mn(III) surface ratio, oxygen vacancies, and reduced copper species, these two latter being key properties for ensuring a high CO conversion percentage as both are active sites for CO oxidation. The reaction temperature and the reactant atmosphere composition seem to be the most important factors for achieving a good catalytic performance, as they strongly determine the location and stability of the reduced copper species.

Synergetic effect of δ/α-Bi2O3 composites on photocatalytic dye degradation and hydrogen production under visible light illumination

Synergetic effect of δ/α-Bi2O3 composites on photocatalytic dye degradation and hydrogen production under visible light illumination

A Low-nanosized Broad Spectrum Photocatalyst for Treatment of Pharmaceutical and Industrial Pollutants: New Ce0.97Fe0.03Zn0.04O2 Composition

A Low-nanosized Broad Spectrum Photocatalyst for Treatment of Pharmaceutical and Industrial Pollutants: New Ce0.97Fe0.03Zn0.04O2 Composition

The Impact of Li2MnO3 Proportion on the Structure and Electrochemical Performance of xLi2MnO3‧(1-x)LiNi1/3Mn1/3Co1/3O2 for Lithium-Ion Batteries

Lithium-rich layered oxides have recently emerged as promising cathode materials for high-energy storage applications.This study focuses on the synthesis of a range of cathode materials using the sol-gel method. These materials are denoted by the molecular formula xLi2MnO3‧(1-x)LiNi1/3Mn1/3Co1/3O2, where x varies from 0 to 1 in increments of 0.3. The main objective is to explore the structure and electrochemical properties of these cathode materials. The presence of a higher Li2MnO3 content was found to stabilize the Li-rich structure and enhance the overall capacity of the electrodes. This stabilization was attributed to the presence of stable tetrahedral Li within the structure. However, it is important to note that the irreversible reaction of Li2MnO3 had a negative effect on the electrode's capacity, resulting in a reduction in overall capacity.The 0.5Li2MnO3‧0.5Li(Ni1/3Mn1/3Co1/3)O2 composition exhibited the best electrochemical performance. It demonstrated a discharge capacity of approximately 250 mAh/g and a capacity retention of around 215 mAh/g after 30 cycles.

Investigating antibacterial activity of biosynthesized silver oxide nanoparticles using Phragmanthera Macrosolen L. leaf extract

The crude leaf extract of Phragmanthera macrosolen L. has been utilized for the first time as an effective reducing, capping and stabilizing agent to synthesize silver oxide nanoparticles (Ag2O NPs) through a green approach. The prepared Ag2O NPs were analyzed by scanning electron-microscopy (SEM), High Resolution Transmission electron microscope (HR-TEM), X-ray diffractions (XRD), Fourier transforms infrared (FTIR) spectroscopy, energy dispersive spectroscopy (EDS), and Ultra-violet visible spectrometry (UV-Vis). The biosynthesized Ag2O NPs applied on gram-positive (S. aureus) and gram-negative (E. coli) bacterial types. FTIR spectral peaks indicate that the phytochemicals in the extract are responsible for the formation of Ag2O nanoparticles. The XRD result shown, poly-crystalline nanoparticles and the average crystalline size calculated was 45.8 nm. UV-Vis analysis shows absorbance existed at 590.5 nm, and the energy band gap calculated through the Tauc relation was 2.1 eV. The SEM images gave a globular and some rod like morphology with diameter of particle obtained between 20.11 and 46.50 nm with some hollow cubic microstructure of Ag2O NPs which makes it suitable for antimicrobial application. The EDS confirms the elemental composition and existence of Ag and O2. The HR-TEM images, specific area electron diffraction (SAED), and XRD patterns confirmed the morphology of Ag2O NPs mean 45.84 nm and polycrystalline nature of the nanoparticles. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 15 and 30 µl respectively for the samples tested. In this study, it was observed that Ag2O NPs highly sensitive to E. coli than s. aureus. The present study revealed that the possible use of green synthesized Ag2O NPs as potential antibacterial agent.

Construction of magnetic Fe2O3-Decorated electroactive Poly(amic acid) composites as recyclable Catalysts: Increased loading of gold Nanoparticles, Controlled Size, and Accelerated catalytic reduction of 4-Nitrophenol

Nanocomposites are widely used in heterogeneous catalysts in the field of water treatment, which exhibit controllable structural advantages and synergistic effects between their components further enhancing catalytic activity. In the current research, we developed the Au nanoparticles immobilized magnetic γ-Fe2O3/Electroactive Poly (amic acid) composite (6Au/EPAA-Fe2O3) prepared by using the in-situ redox reaction strategy. Sundry techniques such as FT-IR, XRD, TGA, SEM/HR-TEM, CV, and XPS analysis have been applied to explain the chemical structure and morphology of as-synthesized composites. The catalytic performance of the catalyst during the reduction of 4-nitrophenol using NaBH4 as a hydrogen donor was assessed in an aqueous medium at room temperature. Attractively, 6Au/EPAA-Fe2O3 composite exhibits superior catalytic performance, which completes the reduction of 4-NP within the 50 s. The pseudo-first-order kinetic rate constants were estimated as 3.0 × 10-2 s−1 for the reduction of 4-NP. Furthermore, the 6Au/EPAA-Fe2O3 composite has excellent stability and reproducibility of 10 consecutive runs by using an external magnet without loss of catalytic activity.

Fe2O3-decorated multiwall carbon nanotube composites for boosted microwave absorption

Developing microwave absorption (MA) materials with a strong absorption ability over a wide bandwidth through a simple and environmentally friendly approach remains a tremendous challenge. Herein, we propose to use an Fe3+–tannic acid framework to assist the dispersion of multi-walled carbon nanotubes (MWCNTs) and successfully prepare MWCNTs/porous carbon/α-Fe2O3 composites through freeze-drying and subsequent heat treatment. The dielectric properties and MA performance can be regulated by the heat treatment temperature, which leads to tunable crystalline structure, composition, and graphitization degree of MWCNTs. Consequently, the MWCNTs/porous carbon/α-Fe2O3 composite heat-treated at 300 °C exhibits a high reflection loss (RL) of −58.9 dB and an effective absorption bandwidth (5.28 GHz) with a matched thickness of 2.26 mm at a filler proportion of only 5 wt%, and the related frequency bandwidth with RL below −10 dB reaches 14.3 GHz at a thickness of 2–5 mm. In conclusion, the balance between conduction and polarization loss endows the composite with excellent impedance matching and boosting MA performance. This study offers a guideline for fabricating excellent MA materials through a simple, environmentally friendly method.

The effect of Y2O3 particles on the microstructure and mechanical properties of tungsten fiber-reinforced tungsten composites

Tungsten fiber-reinforced tungsten (Wf/W) composites are a promising plasma-facing material, and the microstructure at the interface between W fibers and the W matrix greatly impacts performance. In this study, a new kind of Wf/W-Y2O3 composites was developed with the addition of Y2O3 particles to the W matrix in order to modify the interface microstructure between W fibers and the matrix. The microstructure and mechanical properties of these composites were investigated through sintering at temperatures ranging from 1500 °C to 1800 °C. The Y2O3 particles with a face-centered cubic crystal structure were formed at the interface between W fibers and the matrix, which is beneficial for weakening the bonding strength. The Wf/W-Y2O3 composites exhibited pseudo-plasticity at low sintering temperatures, which show the highest bending strength (261 MPa) and fracture energy (6.66 kJ/m2) at 1600 °C. The grains in W particles become the recrystallized nuclei on the surface of W fiber through the bonding of W powder and W fibers. Then, these recrystallized nuclei grow into W fibers by migration of bonding boundaries. However, the Y2O3 particles in the W powder can inhibit the migration of grain boundaries, thereby suppressing the abnormal grain growth behavior at the surface of W fiber.

Physical and chemical characteristics and activity of nickel-modified cobalt-iron-containing catalysts in the reaction of dry reforming of methane

In the process of dry reforming of methane (DRM), the activity of low-percentage catalysts based on cobalt and iron oxides and their modification with nickel oxide was studied. It has been established that the addition of nickel oxide into the Fe2O3/γ-Al2O3 catalyst increases the degree of methane conversion from 14 to 89%, and also increases the yield of target reaction products H2 to 43.0 vol.%, CO to 46.1 vol.% at 850 °C. On a Co3О4-NiО/γ-Al2O3 catalyst at 850 °C, methane conversion reaches to 88.1%, the yield of H2 and CO is 44.8%. TPR-H2 analyzes showed that the introduction of nickel oxide into Fe2O3/γ-Al2O3 composition, in contrast to the Co3O4/γ-Al2O3 catalyst, the temperature peaks of Fe2O3-NiО/γ-Al2O3, reduction shift towards lower temperatures and weaken the interaction of metals with the support - γ-Al2O3 and thereby the amount of active reduced particles of iron and nickel oxides increases, which ensures good catalytic activity of Fe2O3-NiО/γ-Al2O3. According to the XRD results, spinel-like form - NiFe2O4, NiAl2O4 and CoAl2O4, also phase as Fe2O3 were obtained on the Fe2O3-NiО/γ-Al2O3 catalyst. This indicates that the developed catalysts form new phases that are active at high temperatures to produce synthesis gas in reduction-oxidation processes during the DRM reaction.

Electrical and UV-sensing performance of N-doped-Ba(Ti,Zr,Mo,Hf,Ta)O3-dielectric and ZnSnO-channel-based flexible thin-film transistors

Flexible thin-film transistors (TFTs) based on N-doped Ba(Ti,Zr,Mo,Hf,Ta)O3 dielectric and ZnSnO channel show high electrical and UV-sensing performance. The optimal N-doped Ba(Ti,Zr,Mo,Hf,Ta)O3 compositions with low equivalent oxide thicknesses (≈2 nm) and high-entropy (configurational entropy ≈ 1.59 R) are efficiently determined from a wide composition space (library). The film library is patterned to 450 metal–insulator-metal stacks, revealing dielectric constants ≈ 262–322 and loss (tan δ) ≈ 0.01–0.30 for the N-doped Ba(Ti,Zr,Mo,Hf,Ta)O3 at 1 kHz. The library is further integrated to 63 TFTs, and the promising ones exhibit the remarkable parameters: current on/off ratio of 108, threshold voltage (VT) of 0.02 V, saturation field-effect mobility of ≈76 cm2⋅V−1⋅s−1, and subthreshold swing of 0.062 V dec−1. The devices also exhibit desirable long-term stability for up to five months and perform reliably with small or negligible changes in VT and drain-source current under various gate-bias stress and temperature conditions. Furthermore, the TFT-based ultraviolet (253 nm) detector demonstrates impressive sensitivity (≈ 2 × 106) and responsibility (≈ 1171.9 A W−1). There is no substantial degradation in electrical or sensing characteristics under various levels of deformation. Charge transport in constructed energy band diagrams is used to elucidate the observed remarkable performance.

Structural, optical absorption and electrical characteristics of sol-gel synthesized chromium-doped bismuth ferrites

Multiferroic materials have remarkable and several technical uses such as random-access multi-state memories, solar cell devices, data storage recording technologies, etc. An attempt has been made here to synthesize chromium-doped Bi(Fe1-xCrx)O3 (x = 0–0.10) oxides via citrate based sol-gel route and characterized with regards to structural, optical absorption and electrical properties. It depicts a rhombohedral structure with space group R3c for BiFeO3 and Bi(Fe0.98Cr0.02)O3 compositions. The lattice parameters for BiFeO3 on rhombohedral axes are aR ∼5.796 Å, α ∼59.34° which decreases linearly with chromium (x). Similarly, the parameters on hexagonal axes also decrease as aH ∼5.739–5.730 Å, and cH ∼14.269–14.262 Å. However, chromium doping causes a drop in crystallite size and rise in dislocation density. The absorption spectra show a broad peak at λ = 392 nm (for x = 0) and a broader as well as high intense peak for x = 0.02 (λ∼ 393 nm) which is attributed to charge transfer transitions from O2− (2p) valence band to Fe -3d (eg and t2g split levels) conduction band. Band at λ ∼310 nm is associated to the band gap (Eg) of material. Composition Bi(Fe0.98Cr0.02)O3 (x = 0.02) exhibits the highest values of the dielectric constant (εr ∼ 1102), loss (tan δ ∼ 1.1), and least value of impedance. The Cole-Cole plot depicts a depressed semi-circle and indicates presence of loss due to grains only. The room temperature P–E hysteresis loop with remanent polarization (Pr = 0.11439 μC/cm2) and leakage current density (J = 1.1 μA/cm2) are found maximum for Bi(Fe0.98Cr0.02)O3 (x = 0.02). The I-E loop and frequency-dependent P-E loops depict ferroelectric nature of all compositions. The analysis of leakage current density and slope values infer the presence of space charge limited conduction (SCLC) mechanism. These findings suggest materials applications in recent technologies.

Fabrication of NiO-Ce<sub>0.8</sub>Gd<sub>0.2</sub>O<sub>2</sub>-based anode for a solid oxide fuel cell using inkjet 3D printing and study of its microstructure

A paste composition for inkjet 3D printing based on the NiO-Ce0.8Gd0.2O2 composite was developed and an anode billet for a solid oxide fuel cell of planar geometry was made using direct inkjet 3D printing. Effect of the printing mode and thermal annealing on the morphology and structure of the samples has been studied. The anode billet was reduced and the resulting sample was characterized by a number of physicochemical methods.

Interfacial engineering of (Ce,Zr)O2 composite barrier layers for enhancing the durability of solid oxide fuel cells

The dense GdxCe1-xO2 (GDC) barrier layer can't prevent the diffusion of small amounts of Sr through grain boundaries. Recent studies indicate that the (Ce,Zr)O2 composite, placed between GDC and YSZ (Y2O3 stabilized ZrO2) electrolyte, can effectively suppress SrZrO3 formation. In this study, we successfully designed and prepared an anode-supported solid oxide fuel cell (SOFC) with a dense GDC/IDL (interdiffusion layer) composite barrier layer, demonstrates excellent inhibition of elemental diffusion through grain boundaries. Compared with the cell with a single dense GDC barrier layer, the cell with GDC/IDL composite barrier layer exhibits largely improved durability, with a two-fold decreased degradation rate of 2.7 %/kh, operated under constant current density of 400 mA/cm2 at 720 °C. The cell with GDC/IDL barrier layer presents decreased initial performances, with lager Rohm of 0.085 Ω cm2 than 0.075 Ω cm2, and smaller initial Pmax of 0.905 W/cm2 than 1.019 W/cm2 at 750 °C. However, the cell performance surpasses the cell with single GDC barrier after 230 h. Thus, we obtain a new strategy to achieve improved cell durability by sacrificing the cell's initial performance. The in-situ constructed continuous and dense GDC/IDL composite optimizes the electrolyte/cathode interface while maintaining decent electrochemical performance, providing a new horizon to design and prepare high performance and durable SOFCs.

A novel Al/BiCl3/γ-Al2O3 composite for small-sized fuel cell: Fabrication, performance and mechanisms

Small-sized fuel cell is an ideal and promising power source for portable devices due to its long-term electricity supply and free of CO2 emission. However, its commercialization is obstructed by reliable hydrogen source, which should be non-corrosiveness, as compact as possible, stable and controllable high purity hydrogen supply. In this study, a novel in situ hydrogen production material Al/BiCl3/γ-Al2O3 composite is synthesized, which exhibits high hydrogen yield, fast hydrogen production rate and outstanding storage stability. The hydrogen production performance of Al/BiCl3/γ-Al2O3 can be adjusted by changing BiCl3:γ-Al2O3 weight ratio, additive content and milling time. XRD and SEM results indicate that surface cracks, active surface and metal Bi produced in fabrication process lead to the high hydrolysis activity of Al/BiCl3/γ-Al2O3. Mechanism analyses reveal that hydrogen production process is the results of pitting, microgalvanic effect and catalytic effect. Taking into account hydrogen production performance, capacity and cost, Al/5 wt%BiCl3/5 wt%γ-Al2O3 milled for 2 h is a potential hydrogen production material, which can in situ supply hydrogen for small-sized fuel cell.

Electrochemical investigations of chitosan/ZrO2-Bi2O3 composite for advanced energy and environmental applications

Energy needs are on the rise, and the need for effective corrosion resistance measures are also vital to meet the requirements prevailing in society. A multifunctional Chitosan/ZrO2-Bi2O3 composite is synthesized, keeping electrochemical analysis of energy and environmental applications in mind. Various physicochemical methods confirm the impact of integrating ZrO2-Bi2O3 into chitosan, resulting in improved efficacy across applications. The electrocatalytic supercapacitance, hydrogen evolution reaction, and corrosion inhibition studies are carried out to evaluate the efficiency of the synthesized composite. The composite shows a specific capacitance of 636.5 F/g, ensuring the effective utility for supercapacitance applications. The lower overpotential of 135.2 mV is shown by the composite in the electrocatalytic hydrogen evolution reaction. The synthesized composite also shows 96.2 % efficacy in corrosion inhibition studies. The studies conducted demonstrate the increased effectiveness of chitosan when combined with bimetal oxide. The chitosan composite is therefore a competent catalyst for energy and environmental applications.

Investigating and predicting tribological characteristics of AZ31 alloy composites reinforced with nano-Al2O3 and micro-Sn particles: a comparative analysis using CCD-RSM and ANN models

In this research, the central composite-based response surface methodology was adopted to select the dominant optimal input factors on wear behaviour and coefficient of friction of an AZ31-microtin/2 wt% nano-Al2O3 composite prepared through a stir casting process with different wt% of Sn. The input factors, such as wt% of Sn reinforcement, sliding distance, sliding speed, and applied load, were selected to determine their significant effects on the coefficient of friction and wear behaviour with 30 trial runs. Analysis of variance (ANOVA) results indicated that Sn reinforcement plays a significant role in the wear behaviour of the nanocomposites, followed by applied load and sliding distance. In addition, an enhancement in wear resistance was witnessed by the addition of Sn reinforcement with AZ31/nano-Al2O3 composites. The optimal process parameters as per the desirability approach were found to be a weight percentage of Sn: 8%, load: 20 N, sliding speed: 2 m s−1, and sliding distance: 1000 m. According to the ANN results, the predicted data is perfectly acceptable with the actual experimental response value. The R values for the training, validation, and testing phases are 0.96166, 0.96801, and 0.98914 for COF, and 0.97688, 0.99247, and 0.99331 for wear rate, indicating a robust correlation between predicted and actual values. The worn-out pin samples were used to examine the worn surface morphology and analyze the wear mechanism.

Fabrication of Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell and improvement of its photocatalyst properties

Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell structures were made by a two-step method, first, bismuth ferrite nanoparticles by hydrothermal method and then, aniline core-shell by co-precipitation method. The bismuth ferrite (BFO) XRD pattern showed no impurities of Sm, Cr, or their compounds in the samples, indicating that Sm+3 and Cr+3 had been replaced in the BFO structure. The XRD pattern of the Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell shows all peaks of Bi0.90Sm0.1Fe0.97Cr0.03O3 composition with lower intensity, as a result, the Bi0.90Sm0.1Fe0.97Cr0.03O3 composition is phase single. This lower intensity is attributed to the presence of amorphous polyaniline in the core-shell structure. Since there is in the FT-IR spectrum of the Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell, characteristic peaks of both polyaniline and bismuth ferrite simultaneously so, the FT-IR spectrum of the Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell is a perovskite structure. The synthesized samples exhibit weak magnetic properties and behave as a paramagnetic material. The absorption capability of core-shell compared to core nanoparticles has increased in the visible region, and this enhancement is attributed to the influence of the presence of polyaniline. All the peaks in the UV–visible absorption spectrum characterize the nano-sized bismuth ferrite and polyaniline in the UV–visible spectrum of the core-shell. The intensity of the photoluminescence spectrum in the doped sample is significantly higher compared to the core-shell sample. This indicates a much faster recombination rate in the doped nanoparticles compared to the core-shell nanocomposite. The doping of the core with Cr and Sm elements, as well as the coating of the core with a polymeric shell, has led to an increase in the degradation rate of the red dye. We also found that shell thickness plays a vital role in dye degradation efficiency and photocatalytic performance. The Bi0.90Sm0.1Fe0.97Cr0.03O3@PANI core-shell exhibits significant photocatalytic activity under visible light. The photocatalytic studies show that the best sample is Bi0.9Sm0.1Fe0.97Cr0.03O3@PANI core-shell with aniline concentration of 0.2 mL and a pH = 2 which was able to destroy 100 % of Congo red dye molecules.

Enhanced structural, vibrational, and dielectric properties of (Ba0·95Ca0.05) (Ti0.95Zr0.05)1-x(Zn1/3Nb2/3)xO3 ceramics

The (Ba0·95Ca0.05) (Ti0·95Zr0.05)1-x(Zn1/3Nb2/3)xO3 BCZTxZN compounds, were created using the widely adopted solid-state method. To assess the impact of (Zn, Nb: ZN) co-substitution ions we studied the structural, vibrational, and dielectric characteristics of BCZT. The phase purity was validated by conducting Rietveld refinement of XRD data, indicating the coexistence of orthorhombic and tetragonal phases at ambient temperature in the (Ba0·95Ca0.05) (Ti0·95Zr0.05)0.975(Zn1/3Nb2/3)0.025O3 (BCZT25ZN) composition. Furthermore, Raman spectroscopy confirmed the observed transitions. The presence of Zn2+ and Nb5+ ions resulted in a decrease in cell parameters and cell volume. The real part of the dielectric constant and the tangent loss (tan δ) exhibited values of approximately 3380 and 0.031, respectively, for the sample (Ba0·95Ca0.05)(Ti0·95Zr0.05)0.95(Zn1/3Nb2/3)0.05O3 (BCZT50ZN), obtained by substituting ZN in Ba0·95Ca0·05Ti0·95Zr0·05O3. Incorporation of ZN into Ba0·95Ca0·05Ti0·95Zr0·05O3 presents promising prospects for using the material in various device applications, including energy storage capacitors, sensors, and actuators.

Microstructure and mechanical properties of the (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 high-entropy ceramic coating prepared by laser cladding

The (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 high-entropy ceramic coating was fabricated by laser cladding in this study. For the continue and dense coating structure, there were pre-treatments including the squash presetting of feedstock powders and the deposition of Al2O3-TiO2 coating on steel substrate by atmospheric plasma spray. The XRD technology was conducted for investigating the phase transitions during the fabrication of (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 coating. The SEM, EDS technologies and nano-indenter were operated for evaluating the microstructure, composition and mechanical properties of the (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 coating. The results showed that the feedstocks with various structures were successfully transformed into the (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 high-entropy ceramic with rutile structure as well as the formation of intermediate products in similar structures. The (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 coating had a tight combination with the Al2O3-TiO2 coating and showed a thick and compact structure, which included various dendritic crystal structures composed of segregated Al2O3. The (Al1/6Cr1/6Nb1/6Ta1/6Ti1/3)O2 coating exhibited a high level of hardness (13.58 ± 2.05 GPa) and elastic modulus (275.24 ± 32.26 GPa).