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This review discusses the groundbreaking advancements in electric current-assisted sintering techniques, specifically Flash Sintering (FS) and Ultrafast High-Temperature Sintering (UHS), for their application in Solid Oxide Fuel Cells (SOFCs). These innovative sintering methods have demonstrated remarkable potential in enhancing the efficiency and quality of SOFC manufacturing by significantly lowering sintering temperatures and durations, thereby mitigating energy consumption and cost. By providing a detailed overview of the mechanisms, process parameters, and material characteristics associated with FS and UHS, this paper sheds light on their pivotal role in the fabrication of SOFC components such as electrolytes, electrodes, multilayered materials, and interconnect coatings. The advantages, challenges, and prospective opportunities of these sintering technologies in propelling SOFC advancements are thoroughly assessed, underlining their transformative impact on the future of clean and efficient energy production technologies. [ABSTRACT FROM AUTHOR]

In this study, alumina ceramics with hierarchical pores were successfully fabricated using freeze casting. Experimental studies show that both the solid loading of the slurry and the thermal insulation layer at the interface of the slurry and cooling plate can influence the pore characteristics of cast samples. In order to examine the pore characteristics and evaluate the permeability of the freeze-cast samples fabricated under different conditions, a generative adversarial network (GAN) method was employed to reconstruct the three-dimensional (3D) microstructure from two-dimensional (2D) scanning electron microscopy (SEM) images of the samples. Furthermore, GAN 3D reconstruction was validated against X-ray tomography 3D reconstruction results. Based on the GAN reconstructed microstructures, the permeability and pore distribution of the various samples were analyzed. The sample cast with 35 wt.% solid loading shows an optimal permeability. [ABSTRACT FROM AUTHOR]

In recent years, the burgeoning imperative of energy-efficient building management practices has surged dramatically, underscoring an urgent mandate for comprehensive studies that integrate cutting-edge optimization algorithms with precise heating load forecasting techniques. These studies are not merely endeavors; they represent concerted efforts to increase building energy efficiency and address mounting concerns regarding sustainability and resource utilization. In the intricate domain of heating, ventilation, and air conditioning (HVAC) systems, energy optimization challenges are being meticulously confronted through rigorous exploration and the application of innovative problem-solving methodologies. This pioneering study introduces groundbreaking methodologies by seamlessly integrating two state-of-the-art optimization algorithms— the Red Fox Optimization and the Golden Eagle Optimizer— with the Decision Tree model. This fusion is aimed at enhancing the accuracy of heating load predictions and streamlining HVAC system optimization processes, marking a significant leap toward achieving heightened energy efficiency and operational efficacy in building management practices. The study emphasizes the significance of precise heating load prediction in advancing energy efficiency, realizing cost savings, and fostering environmental sustainability in building management. Furthermore, it delves into the multifaceted impact of various building features on heating load, encompassing variables such as glazing area, orientation, height, relative compactness, roof area, surface area, and wall area. These insights furnish actionable intelligence for refined decision-making processes in both building design and operation. Based on the results, the DT single model experienced the weakest performance among the three models, with R2 = 0.975 and RMSE = 1.608. The model DTFO (DT + FOX) achieves an extraordinary R2 value of 0.996 and RMSE value of 0.961 for heating load prediction, surpassing the performance benchmarks set by other models. This achievement holds considerable promise for aiding engineers in crafting energy-efficient buildings, particularly within the swiftly evolving landscape of smart home technologies. [ABSTRACT FROM AUTHOR]

Research on polymer-based dielectric materials with low energy loss and high power density for dielectric capacitors can promote the development of advanced energy storage devices and effectively solve energy storage problems. In recent years, all-organic polymer dielectrics have received extensive attention due to the excellent properties and have shown broad development prospects in the energy storage industry. Compared to polymer inorganic composites with bad processability, all-organic dielectrics have proven to be a more suitable option for low-cost and large-scale production. This review summarizes the phased achievements of traditional all-organic polymer dielectrics and the recent progress in polymer modification technology. Meanwhile, the energy storage theory of dielectrics, such as energy storage parameters, polarization mechanisms, breakdown mechanisms, and conduction mechanisms, is thoroughly reviewed. Finally, this paper identifies the existing problems of all-organic polymer dielectric materials and proposes feasible solutions and possible future research priorities. [ABSTRACT FROM AUTHOR]

The behaviour of various powder systems during high temperature sintering has been investigated by coupling X-ray microtomography and discrete element method (DEM). Both methods are particularly relevant to analyse particle interactions and porosity changes occurring during sintering. Two examples are presented. The first one deals with a copper powder including artificially created pores which sintering has been observed in situ at the European synchrotron and simulated by DEM. 3D images with a resolution of 1.5 μm have been taken at various times of the sintering cycle. The comparison of the real displacement of particle centers with the displacement derived from the mean field assumption demonstrates significant particle rearrangement in some regions of the sample. Although DEM simulation showed less rearrangement, it has been able to accurately predict the densification kinetics. The second example concerns multilayer ceramic capacitors (MLCCs) composed of hundreds of alternated metal electrode and ceramic dielectric layers. The observation of Ni-based MLCCs by synchrotron nanotomography at Argon National Laboratory with a spatial resolution between 10 and 50 nm allowed understanding the origin of heterogeneities formed in Ni layers during sintering. DEM simulations confirmed this analysis and provided clues for reducing these defects.

The demand for a new generation of high‐energy‐density dielectric materials in the field of capacitive energy storage is promoted by the rise of high‐power applications in electronic devices and electrical systems. Polymer‐based dielectric nanocomposites with ultrahigh charge–discharge rates and power densities play essential roles in energy storage. Recently, multilayer structure polymer‐based dielectric nanocomposites (MSPBDNs) with improved dielectric constant, breakdown constant, and discharged energy density have gained widespread interest because of their immense potential. In the present work, MSPBDNs are classified, depending on the nature of the interlayer, into those with a high insulation layer, a high dielectric layer, and a gradient structure. To further understand the breakdown process of MSPBDNs, the authors elaborate on multilayer‐structured models, analysis breakdown mechanisms, and simulations. Despite the great progress achieved, the field of developing a novel topological structure remains open to further investigation and optimization. In addition, the research prospects and directions of energy storage fields are briefly discussed and summarized. [ABSTRACT FROM AUTHOR]

Microstructural parameters such as triple phase boundary (TPB) density, surface area density, connectivity and tortuosity of different phases strongly influence the performance of solid oxide fuel cells (SOFCs). In this study, the effect of the powder morphology on the microstructural parameters of a La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 (LSCF) cathode is comprehensively examined using Kinetic Monte Carlo (KMC) simulations. A number of numerical samples consisting of spheres or clumped spheres are created using a Discrete Element Method (DEM), taking into account the powder morphology such as particle size, particle size distribution, particle aspect ratio and sphericity, and particle orientation. The DEM-generated numerical structures with different particle morphologies are submitted to the KMC simulations. Their effects on relative density, densification rate, surface area density, tortuosity factor of LSCF phase and tortuosity factor and connectivity of the pore phase are compared and analyzed. [ABSTRACT FROM AUTHOR]

Synchrotron X-ray computed nanotomography (nCT) and Focused Ion Beam-Scanning Electron Microscope nanotomography (FIB-nT) were used to characterize baked-out and sintered nickel (Ni) electrode-Multilayer Ceramic Capacitors. The three-dimensional microstructures obtained by two different tomography techniques were quantified and correlated. X-ray nCT is sufficient to reveal the pore characteristics, whereas the FIB-nT enables the particles in the initial packings to be identified. In the dielectric ceramic layers, pores preferentially orient horizontally in the layer and the regions near the Ni/BT interface are denser than the inner regions. This anisotropy is possibly caused by compressive stress induced during the heating stage. [ABSTRACT FROM AUTHOR]

This letter reports on in-situ characterization of the high temperature sintering of multilayer ceramic capacitors by high-resolution synchrotron x-ray imaging. Microstructural evolution was obtained in real time by a continuous recording of 2-dimensional radiographs. Anisotropic strains were measured for different layers. Quantification of defects was conducted with 3-dimensional nano-computed tomography. These in-situ observations prove that electrode discontinuities occur at the early stage of sintering and originate from initial heterogeneities linked to the particulate nature of the starting powders. [ABSTRACT FROM AUTHOR]

Abstract: In the design of liquid–metal fusion blankets, Al2O3 ceramic is one of the most promising coating materials. In this study, functionally graded FeAl/Al2O3 coatings were deposited on China Low Activation Martensitic (CLAM) steel substrates with vacuum plasma spraying (VPS) method. The SEM investigation revealed that the adhesion between adjacent layers in the coatings was sound. X-ray diffraction showed that stable alpha alumina dominated in the top alumina layers, while γ-Al2O3 and β-Al2O3 were also detected. The coating/substrate adhesive tensile strength test showed that adhesive strength of graded coatings was about 2.5 times that of duplex FeAl/Al2O3 coatings. Thermal shock resistance test indicated that the graded coatings could tolerate more thermal shock cycles than duplex coatings. [ABSTRACT FROM AUTHOR]

Synchrotron x-ray nano-tomography was used to characterize the microstructures of multi-layer ceramic capacitors before and after sintering. 3D microstructures of the same sample were reconstructed and quantitatively analyzed. The discontinuities observed in inner electrodes were found to originate from initial heterogeneities of nickel powders in the electrodes. They are supposed to grow due to the constraint of adjacent dielectric layers. Dielectric layers show anisotropic shrinkage with a decrease in density as function of layer position in the multilayer. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method for narrowing the spectrum in high-power narrow-linewidth polarization-maintaining (PM) fiber amplifiers and investigate its potential for suppressing the stimulated Brillouin scattering (SBS). In this method, in addition to common phase modulation to suppress SBS, precisely designed amplitude modulation is induced to generate self-phase modulation in a high-power PM fiber amplifier. In this co-modulation way, the spectrum can be gradually compressed along the fiber. Compared to phase modulation alone or fiber-Bragg-gratings (FBGs) based narrow-linewidth fiber oscillator schemes, in which the spectrum remains the same or broadens, this scheme can achieve a higher SBS threshold for the same output spectral linewidth. Experiments on a ∼ 3 kW peak power quasi-continuous wave (QCW) fiber amplifier show that the co-modulation scheme can compress the spectrum from 0.25 nm to 0.084 nm as output peak power increases from 13 W to 3.2 kW and enhances the SBS threshold by ∼1.7 times compared to traditional FBGs-based fiber oscillator schemes, and by ∼1.4 times compared to common phase modulation schemes. This co-modulation scheme has the potential for mitigating SBS in high-power fiber amplifiers.

Na 0.5 Bi 0.5 TiO 3 (NBT) ceramic is the promising dielectric material for energy storage devices due to its high maximum polarizability and temperature stability. However, its low breakdown strength limits its application. Here, we prepared 0-3 type composite 0.45Na 0.5 Bi 0.5 TiO 3 -0.55Sr 0.7 Bi 0.2 TiO 3 / x wt % AlN (NBT-SBT/ x AlN) to increase the breakdown strength. The effects of the various AlN contents on the phase composition, microstructures, dielectric, and energy storage properties of NBT-SBT were systematically discussed. The result showed that the enhanced energy storage properties were obtained by introducing AlN particles. The NBT-SBT/6AlN composite ceramics showed a high breakdown strength of 360 kV/cm, large energy density of 5.53 J/cm 3 , and energy efficiency of 90%. Meanwhile, the excellent frequency (10-500 Hz) and temperature stability (25-125 °C) were exhibited with the fluctuation of energy storage within 9% and energy efficiency more than 87%, suggesting that the 0-3 composite NBT-SBT/ x AlN is a candidate dielectric material for the dielectric energy storage.