Crystal Microstructure Research Articles

THE EFFECT OF CALCINATION TEMPERATURE AND HOLDING TIME ON STRUCTURAL PROPERTIES OF CALCIA POWDERS DERIVED FROM EGGSHELL WASTE

This study investigates the effects of calcination temperature and holding time on the structural properties of calcia (CaO) powders. The raw material used in this study is chicken eggshell waste, which was cleaned, dried, ground, and sieved for uniform particle size. The synthesis of calcia powder was performed by calcining the powder at 900°C and 1000 °C for 5, 10, and 15 hours. XRD, BET, and SEM analyses were employed to evaluate crystal structure, textural properties, and microstructure of the calcined powders. The Rietveld analysis reveals the identified crystalline phases were calcia up to 95.6 mol% and calcium hydroxide as secondary phase. Results indicate that higher calcination temperatures and extended holding times increase particle size and reduce BET surface area, significantly altering pore size distribution. Specifically, elevated temperatures promote sintering and grain growth, leading to smaller average pore radii and decreased total pore volume. The BET surface area ranges from 7.431 m2/g to 1.772 m2/g for samples calcined at 900 °C and from 3.202 m²/g to 0.711 m²/g for samples calcined at 1000 °C. Correspondingly, the average particle radius increases from 183.51 nm to 769.55 nm at 900 °C and from 425.83 nm to 1918.10 nm at 1000 °C as the holding time extends. BJH analysis reveals that longer holding times broaden pore size distribution due to the merging of smaller pores.

Influence of the Sodium Titanate Crystal Size of Biomimetic Dental Implants on Osteoblastic Behavior: An In Vitro Study.

Treating the surfaces of dental implants in an alkaline medium allows us to obtain microstructures of sodium titanate crystals that favor the appearance of apatite in the physiological environment, producing osteoconductive surfaces. In this research, 385 discs made of titanium used in dental implants underwent different NaOH treatments with a 6M concentration at 600 °C and cooling rates of 20, 50, 75, and 115 °C/h. Using high-resolution electron microscopy, the microstructures were observed, and the different crystal sizes were determined and compared with control samples (those without biomimetic treatment). Roughness, wettability, surface energy and the sodium content of the surface were determined. The different surfaces were cultured with human osteoblastic cells; cell adhesion was determined at 3 and 14 days, and the degree of mineralization was determined at 14 days via alkaline phosphatase levels. Variations in the microstructure and size of sodium titanate crystals in NaOH solutions rich (1 g/L) or low in calcium (approximately 100 ppm) were determined. The results show that as the cooling rate increases, the size of the crystals decreases (from 0.4 μm to 0.8 μm) except for the case of 115 °C/h, when the rate is too fast for crystalline nucleation to occur on the surface of the titanium. The thermochemical treatment does not influence the roughness or the cooling rate since a Sa of 0.21 μm is maintained. However, the presence of titanate causes a decrease in the contact angle from 70° to 42° and, in turn, causes an increase in the total surface energy from 35 to 49.5 mJ/m2, with the polar component standing out in this energy increase. No variations were observed in the thermochemical treatments in the presence of sodium, which was around 1200 ppm. It was observed that as the size of the crystals decreases, cell adhesion increases at 3 days and decreases at 14 days. This is because finer crystals on the surface are already in the mineralization process, as demonstrated using the level of alkaline phosphatase that is maximal for the cooling rate of 75 °C/h. It was possible to confirm that the variations in the concentrated NaOH solutions with different calcium contents did not affect the crystal sizes or the microstructure of the surface. This research makes it possible to obtain dental implants with different mineralization speeds depending on the cooling rate applied.

Novel high-TC piezo-/ferroelectric ceramics based on a medium-entropy morphotropic phase boundary design strategy

The medium- or high-entropy strategy has emerged as a new paradigm for designing high-performance piezoelectric ceramics. However, the effectiveness of this approach remains unclear to the development of high Curie temperature (TC) piezo-/ferroelectric materials with outstanding performance. To develop high-performance piezo-/ferroelectric materials suitable for high-temperature environments, in this work, we design a novel ceramic system based on a medium-entropy morphotropic phase boundary (ME-MPB) strategy. Piezo-/ferroelectric ceramics of the formula, Pb(Yb1/2Nb1/2)O3–Pb(In1/2Nb1/2)O3–PbTiO3, meeting the medium entropy criteria, were successfully synthesized using the conventional solid-state reaction method. The crystal structure, microstructure, dielectric, piezoelectric, and ferroelectric properties of the ceramics of the ME-MPB compositions were systematically investigated. X-ray diffraction and scanning electron microscopy analyses revealed that these ceramics possess a pure perovskite phase and dense microstructure. Notably, the prepared ceramics exhibited exceptional piezoelectric performance, with a high d33 up to 603 pC/N, a large strain of 0.20%, a high remanent polarization of 44.0 μC/cm2, and a high Curie temperature of 362 °C. This study demonstrates an effective design approach based on the ME-MPB strategy and points out a new pathway for developing high-performance materials for high-temperature applications as sensors, thereby expanding the research perspective on the design of medium-entropy piezo-/ferroelectric ceramics.

Tetrafluoro(aryl)sulfanylated Bicyclopentane Crystals That Self-Destruct upon Cooling.

Whereas single crystals of organic compounds that respond to heat or light have been reported and studied in detail, studies on crystalline organic compounds that elicit an extreme mechanical response upon cooling to very low temperatures are relatively rare in the chemical literature. A tetrafluoro(aryl)sulfanylated bicyclopentane synthesized in our laboratory was discovered to exhibit such behavior; i.e., the crystals jumped and forcefully disintegrated upon cooling below ∼193 K. Accordingly, the origin of this low-temperature thermosalient effect was investigated through NMR, SC-XRD, PXRD, microscopy, DSC, Raman, and Brillouin experiments. To our surprise, NMR, SC-XRD, PXRD, and DSC experiments suggest the phenomenon can neither be attributed solely to a chemical transformation nor a phase transition of the entire material. Rather, XRD, Raman, and Brillouin experiments provide evidence that built-up strain released from the crystal upon self-destruction may be associated with crystal microstructure or a phase transition that occurs in another material (i.e., an impurity) in the crystal. This study demonstrates that molecular structural changes in organic material microstructure or impurity phases (which may not necessarily be visible by X-ray diffraction) can have a significant impact on the behavior of the bulk crystalline material. Thus, the role of microstructure may be considered more heavily in future mechanistic studies on mechanically responsive crystals.

The influence of impact loading on microstructure and texture of copper single crystals of nominally stable orientations

Abstract In this study, single-crystal samples of pure copper with stable orientations – Br (110)[112] and G(110)[001] – were impact-loaded in a channel die, with the punch driven by explosive energy, to achieve a strain rate of 4 × 105 s−1. Microstructural characterization was conducted on samples deformed up to 60%, using optical microscopy and SEM across a wide range of scales. Texture evolution was analysed through X-ray diffraction and SEM/EBSD. Both orientations exhibited highly unstable behaviour due to deformation twinning and the development of plastic flow instabilities in the form of deformation bands. In G(110)[001]-oriented crystals, twinning occurred on two planes, while in Br(1-10)[112]-oriented crystals, twinning occurred on all four {111} planes, which are highly favoured for slip activity during deformation. The formation of plastic flow instabilities in narrow regions resulted from the dominance of a single slip system in selected regions of the Br-oriented crystal, or a pair of highly favoured slip systems in the G orientation.

The effect of Aluminum (Al) ratio on the synthesis of the laminated Mn2AlB2 MAB Phase

MAB phases have recently garnered significant interest due to their excellent properties, such as high thermal and electrical conductivity, oxidation resistance, and exceptional corrosion resistance. Although the Mn2AlB2 phase has been synthesized using multiple methods recently, it requires long experimental durations (up to 7 days), high costs, and extensive experimental efforts to achieve high purity. In our study, the Mn2AlB2 MAB phase was synthesized using Al, B, and Mn as precursor materials. Specifically, we investigated the effect of Al ratios (Al:1.3, Al:3, and Al:10) on the formation of the Mn2AlB2 MAB phase. The precursor powders were mixed homogeneously in stoichiometric ratios using ball milling and cold-pressed in a 1-inch die set to form green pellets, which were then sintered in a high-temperature vacuum furnace at 1200°C. The resulting Mn2AlB2 MAB phase were characterized in terms of crystal structure, impurity, and microstructure using XRD, FESEM, and EDS.

Fast-Charging Solid-State Li Batteries: Materials, Strategies, and Prospects.

The ability to rapidly charge batteries is crucial for widespread electrification across a number of key sectors, including transportation, grid storage, and portable electronics. Nevertheless, conventional Li-ion batteries with organic liquid electrolytes face significant technical challenges in achieving rapid charging rates without sacrificing electrochemical efficiency and safety. Solid-state batteries (SSBs) offer intrinsic stability and safety over their liquid counterparts, which can potentially bring exciting opportunities for fast charging applications. Yet realizing fast-charging SSBs remains challenging due to several fundamental obstacles, including slow Li+ transport within solid electrolytes, sluggish kinetics with the electrodes, poor electrode/electrolyte interfacial contact, as well as the growth of Li dendrites. This article examines fast-charging SSB challenges through a comprehensive review of materials and strategies for solid electrolytes (ceramics, polymers, and composites), electrodes, and their composites. In particular, methods to enhance ion transport through crystal structure engineering, compositional control, and microstructure optimization are analyzed. The review also addresses interface/interphase chemistry and Li+ transport mechanisms, providing insights to guide material design and interface optimization for next-generation fast-charging SSBs.

Chromogenic Photonic Crystal Detectors for Monitoring Small Molecule Diffusion at Solid-Solid Interfaces Using Stimuli-Responsive Shape Memory Polymers.

In situ monitoring of small molecule diffusion at solid-solid interfaces is challenging, even with sophisticated equipment. Here, novel chromogenic photonic crystal detectors enabled by integrating bioinspired structural color with stimuli-responsive shape memory polymer (SMP) for detecting trace amounts of small molecule interfacial diffusion are reported. Colorless macroporous SMP membranes with deformed macropores can recover back to the "memorized" photonic crystal microstructures and the corresponding iridescent structural colors when triggered by diffused small molecules. Systematic experimental and theoretical investigations using various microscopes, optical spectroscopy and modeling, spatio-resolved energy-dispersive X-ray spectroscopy, and theoretical diffusion calculations confirm the diffusion-induced shape memory and chromogenic mechanisms. Importantly, proof-of-concept sensing of temporospatial-resolved diffusion of bioactive ingredients used in drug delivery, including anti-inflammatory methyl salicylate in pain relieving patches and vitamin E barriers loaded in contact lens, and phthalates plasticizers in commercial PVC products has been demonstrated. These innovative detectors are inexpensive, reusable, and easy to operate and deploy for both qualitative and quantitative analyses, promising for opening new avenues in biomedical research, threat detection, and monitoring of plastics, food, and environmental safety. Moreover, reconfigurable photonic crystals with micrometer-scale resolution, which are of great importance in tunable and integrated nanooptics, can be fabricated by diffusion-enabled microcontact printing.

A study on the influence and mechanism of the microstructure of tourmaline crystal on its piezoelectricity

A study on the influence and mechanism of the microstructure of tourmaline crystal on its piezoelectricity

Structural and Grain-Growth Evolution during Synthesis of Layered Li(Ni,Co,Mn)O2 Oxides through Co-Precipitation Process

For meeting 2050 zero carbon goals, the renewable energy/electricity including solar cells and wind mills need to be stored in a good energy storage system such as Li ion batteries. Furthermore, the electrification of transportation such as electric vehicles also need Li ion batteries in a very large scale. In recent years, µm-sized layered oxides, namely single crystals, received great attention due to its enhanced cycled-electrochemical performance.For conventional/commercial NMC layered oxides, integrated co-precipitation process is commonly used. In additions, “single-crystal” process typically requires more heat energy at higher temperatures. Therefore, the main objective of this study is to develop a cost-effective process for the synthesis of single-crystal Ni-rich layered oxides electrode. For instance, the synthesis of layered oxides may adopt the simple solid state reaction routes. The heating procedures may be optimized through the understanding of calcination and grain-growth processes. Ni-rich layered oxides, namely NCA and NMC 811 are selected and prepared. The crystal structure and microstructure of cathodes were examined using XRD and SEM. The electrochemical properties are monitored using CV, EIS and charge/discharge tests.

Exploring Na-Based Oxides as Electrode Materials for Alkali Metal Thermal-to-Electric Converters

The alkali metal thermal-to-electric converter (AMTEC) is a technology that converts thermal energy into electrical energy. It can operate with various heat sources, does not require fuel injection, and produces no harmful emissions, making it an environmentally friendly technology. Currently, Mo-based metallic materials are mainly used as electrode materials for AMTEC. However, when operated at temperatures above 800°C, the coarsening of electrode particles and the formation of Na-Mo-based secondary phases have a negative impact on the durability of the cell. In this study, Na-based oxides, widely known as electrode materials for secondary batteries, were applied as electrode materials for AMTEC. The electrode materials were synthesized via a solid-state reaction method that involved grinding and heat treatment at 950°C. The crystal structure and microstructure of the materials were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. To facilitate effective coating of the electrode material onto the surface of the beta-alumina solid electrolyte (BASE), physical treatments (e.g., sandpapering) and chemical treatments (e.g., chemical etching) were employed to optimize the BASE surface. Through this process, it was confirmed that the interface contact between the electrode and the BASE was successfully formed after chemical treatment. For electrochemical performance evaluation, cells with small-area and large-area electrodes were prepared by coating the cylindrical BASE surface. At an operating temperature of 600°C, the small-area cell (electrode area: 3 cm²) exhibited a maximum power output of approximately 1.02W (0.34W/cm2). The large-area cell (electrode area: 4.2 cm²) achieved an excellent power output of 10.13W (0.23W/cm2). This study confirmed for the first time that Na-based oxide electrode materials show great potential as electrodes for AMTEC. The detailed findings of this research will be discussed further in the presentation.

Processing of Dense BaCe0.4Zr0.4Y0.2O3-Δ Proton-Conducting Electrolyte for Direct Ammonia Fuel Cell Applications

Proton conducting oxide such as BaCe0.4Zr0.4Y0.2O3-δ(BCZY) electrolyte is known for its unique stability and high ionic conductivity due to the doping effect from the substitution of Zr and Y for Ce ions. For reaching the 2050 net-zero carbon goal, ammonia has been recognized as an important H2 carrier for ease transportation. Thus, using the proton conductor as an electrolyte for ammonia applications including conversion and synthesis provides extra advantages such as lower operation temperatures, negligible NOx emission and better kinetics. Thus, solid oxide cells based on a BCZY proton conducting electrolyte received great attention not only for green hydrogen but also ammonia fuel.However, the densification of BCZY needs heating temperatures as high as 1400°C. Although the adoption of sintering additives such ZnO or NiO in BCZY has shown some improvement, the densification mechanism remains ambiguous. Thus, the objective of this study is to understand the role and mechanism of adding sintering additive in BCZY. The influence of composite electrode processed at lower temperature on its performance will be also discussed due to the better-densified BCZY. In additions, the resulted electrical and structural properties will be analyzed and discussed based on reactions and densification through heating process. The crystal structure and microstructure of densified BCZY was also characterized using XRD, field-emission SEM, and STEM.

Enhancing Lithium-Ion Battery Performance through Dual Doping in Ni-Rich Cathodes

Doping is crucial for maintaining the long-term stability of Ni-rich layered cathodes in lithium-ion batteries. However, using a single dopant is often insufficient in achieving a stable, high-energy cathode material. In this study, we used a dual doping approach by employing Al3+ and Nb5+ ions to enhance the cycling stability of Li[Ni0.92Co0.04Mn0.04]O2 (NCM92) cathodes. Al3+ doping reinforces the crystal structure, while Nb5+ doping optimizes the morphology of primary particles. This dual doping strategy not only harnesses the advantages of both dopants simultaneously, but also showcases remarkable performance improvements through synergistic effects. The resulting Li[Ni0.905Co0.04Mn0.04Al0.005Nb0.01]O2 (AlNb-NCM92) cathode, developed via dual Al and Nb doping, demonstrates remarkable stability. These findings highlight the importance of a comprehensive doping strategy that considers both crystal structure and microstructure to maximize the long-term stability of high-energy Ni-rich cathode materials.

Influence of polymorphism on the lattice thermal conductivity of Ga2O3

In this paper, the lattice thermal conductivity of Ga2O3 in its β, α, ɛ(κ), and γ phase is systematically investigated based on the first principles calculation and iterative approaches to solve the phonon Boltzmann equation. The results indicate that the crystal microstructure of Ga2O3 has a significant effect on the lattice thermal conductivity. In addition, the results also find that γ-Ga2O3 has an ultralow lattice thermal conductivity within the temperature range from 50 to 700 K. As for γ-Ga2O3, the obtained lattice thermal conductivity at room temperature (300 K) is 0.1189 W/(m K) along the [100] and [010] directions, and 0.1159 W/(m K) along the [001] direction. The lattice thermal conductivity exhibits the following order: γ-Ga2O3 ≪ ɛ(κ)-Ga2O3 < α-Ga2O3 < β-Ga2O3. The disruptive effect of Ga3+ cation vacancies on the spinel structure's symmetry is responsible for the ultralow lattice thermal conductivity observed in γ-Ga2O3. This disruption increases the complexity of the lattice and hampers the propagation and scattering of phonons. Another contributing factor is the presence of weak chemical bonding, which intensifies the oscillation of Ga atoms. The results of this study have significant implications for further investigating the factors influencing the thermal conductivity of Ga2O3 and developing thermoelectric materials.

Non-Isothermal Crystallization Kinetics and Properties of CaO-Al2O3-SiO2 (CAS) Glass-Ceramics from Eggshell Waste, Zeolite, and Pumice.

In this study, the crystallization behavior, microstructure, and mechanical and physical properties of CaO-Al2O3-SiO2 (CAS)-based glass-ceramics prepared from eggshell waste, zeolite, and pumice were investigated using X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron microscopy (SEM), a nanoindentation tester, and the Archimedes method. XRD analysis revealed that anorthite and wollastonite crystalline phases precipitated in the glass-ceramic samples after sintering at temperatures of 1000 °C and 1100 °C. However, diffraction peaks belonging to the wollastonite phase disappeared after sintering at 1200 °C, while peaks representing the pseudowollastonite phase were detected together with anorthite in the samples. SEM images showed that the crystals become coarser as the sintering temperature increased, with the crystal morphology transitioning from needle-like to rod-like. The crystallization activation energy (Ea) and Avrami parameter (n), both kinetic parameters, were calculated from DTA curves plotted at different heating rates using the Kissinger, Ozawa, and Matusita approaches. The results indicated that the crystallization activation energy of the CASZ glass ranged from 406 to 428 kJ mol-1, while that of the CASP glass varied from 356 to 378 kJ mol-1, depending on the method used. Additionally, the Avrami constant (n) was calculated to be 3.33 for CASZ and 2.89 for CASP. The hardness and bulk density of the glass-ceramic samples were significantly affected by the porosity present in the structure, with the highest hardness and bulk density values achieved for the CASZ glass-ceramic sample at the initial sintering temperature of 1000 °C.

Immobilization and coordination chemistry of Friedel’s salt (Ca/Al-LDHs) on heavy metals removal

Friedel’s salt (F’s salt, FS, Ca/Al-LDHs) was prepared via coprecipitation synthesis to remove Pb(II) and Zn(II). The adsorption of F’s salt on Pb(II) and Zn(II) was a physical adsorption process and could be well described by pseudo-second order kinetics. The adsorption process is mainly completed by surface adsorption of pore structure and interlayer structure. In addition, the crystal microstructure parameter, molecular structure and elemental spatial distribution analysis results demonstrated that Pb(II) and Zn(II) could form new solid solutions such as Pb/CaAl-Cl-LDHs, CaZn/Al-Cl-LDHs and Zn/CaAl-Cl-LDHs via lattice replacement, and then effectively immobilized in F’s salt crystals. Unlike Pb(II), there are two fixed lattice substitution pathways for Zn(II), that is, Ca(II) and Al(III) can be used as replacement objects. Notably, the chemical bonding mechanism is more prominent for the solidification of Pb(II) than that of Zn(II) in F’s salt. Moreover, the superficial coordination chemistry analysis results revealed that the abundant OH groups distributed in the main layer laminate structure can also serve as the binding sites for Pb(II) and Zn(II). This study provides a theoretical basis and novel insights into the immobilization mechanism of Pb(II) and Zn(II) in F’s salt.

High energy storage capacity and relaxation ferroelectric characteristics of fine-grained Ba0.99Bi0.01TiO3@MnO core-shell nanoceramics

A novel core-shell structured Ba0.99Bi0.01TiO3@xMnO (BBT@MnO) (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0 mol%) relaxation ferroelectric ceramics were prepared by co-precipitation method. The structures, insulating, dielectric, and energy storage properties of the BBT@MnO ceramics were systematically investigated. According to TEM, the particles had a diameter of about 430 nm, high uniformity, and high dispersity. They were fabricated using a coating technique to simultaneously improve both the dielectric breakdown strength (BDS) and densification of the ceramics. The thickness of the MnO layers in the BBT@MnO particles averaged about 19 nm. Complex impedance testing of BBT@MnO ceramics revealed that only a one-grain boundary response existed for all ceramics, with the best insulating properties at x = 0.4 mol%. Furthermore, MnO coating increased lattice distortion and polarization intensity, altering the crystal structure and microstructure morphology while increasing energy storage density. The ceramics with 0.4 mol% MnO coating showed thin P-E hysteresis loops, with an optimal dielectric constant of 3610, a dielectric loss of 0.01, and the discharged energy density (Jd) of 0.26 J/cm3 and efficiency (η) of 76.5 %. The results showed that MnO coating is beneficial for reducing dielectric loss and improving insulation performance. This study provided valuable insights for the research of lead-free dielectric ceramic capacitors, and the BBT@MnO ceramics present good development prospects in high-power pulse energy storage systems.

Comparison study on the effect of oxygen, nitrogen and hydrogen absorption on phase transformation and mechanical properties of quenched CP Ti and Ti6Al4V alloy

Microstructures and mechanical properties of commercial pure Ti and Ti6Al4V metal were studied after water quenching. The nitrogen (N), oxygen (O) and hydrogen (H) analysis was conducted on the quenched samples to establish the effect of impurities on phase transformation and mechanical properties. It was found that despite some negligible increment on the impurities, they could not be attributed to structural change but rather stabilization of the metastable FCC induced by rapid cooling. The formation of the metastable FCC phases was attributed to stresses induced by high cooling rates upon water quenching. Quenching from high temperatures has a significant effect on the crystal structure, microstructure and mechanical properties.

Study on Microstructure and Properties of AlCoCrFeNi High-Entropy Alloys by Extreme High-Speed Laser Cladding

AlCoCrFeNi HEA powders were cladded onto AISI 1045 steel using EHLA and CLA, respectively. The phase composition, microstructure, micro/nanohardness, and corrosion resistance of the two coatings were compared and analyzed. The results show that the phase structure of AlCoCrFeNi HEA coatings prepared by EHLA and CLA was that of a BCC/B2 phase solid solution. From the bottom to the top, the EHLA-derived AlCoCrFeNi HEA coating experienced evolution in the microstructure of plane crystal, dendrite, and equiaxed crystal. The micro/nanohardness of EHLA-derived coating (~507 HV0.2, 6.716 GPa) is higher than that of CLA-derived coating (~429 HV0.2, 5.778 GPa). The electrochemical test results show that the Ecorr of CLA is −0.527 V and the Icorr of CLA is 1.272 × 10−7 A/cm2, while the Ecorr of EHLA is −0.454 V and the Icorr of EHLA is 1.588 × 10−8 A/cm2, which means that the corrosion resistance of EHLA is better.

Preparation and performance study of solid electrolyte Ce0.80Gd0.04Sm0.04Er0.04Y0.04RE0.04O2-δ (RE= Yb, Dy, Eu, Nd, Pr, La)

The production of highly conductive electrolytes has been a crucial factor in the practical development of Solid Oxide Fuel Cells (SOFCs). This study highlights the impact of different dopants on the crystal structure, microstructure, and ionic conductivity of a ceria-based matrix within the Ce0.80Gd0.04Sm0.04Er0.04Y0.04RE0.04O2-δ system. The Ce0.80Gd0.04Sm0.04Er0.04Y0.04RE0.04O2-δ (RE = Yb, Dy, Eu, Nd, Pr, La) powders were prepared using the solid-state reaction method. The phase structure, microstructure, and ionic conductivity of the GSEYRE series electrolytes were analyzed using XRD, SEM, EDS, TEM, XPS, AC impedance spectroscopy, and thermal expansion analysis. Phase structure analysis confirmed that all multi-doped electrolytes possessed a cubic fluorite structure with the Fm3m space group. After sintering at 1400 °C for 10 h, all samples exhibited densities exceeding 94 %. XPS analysis revealed a high concentration of oxygen vacancies in the GSEYRE. Electrical performance analysis showed that the Ce0.80Gd0.04Sm0.04Er0.04Y0.04Dy0.04O2-δ (GSEYD) electrolyte demonstrated the highest ionic conductivity (σt = 3.36 × 10−2 S/cm) and the lowest activation energy (Ea = 0.78 eV) at 800 °C. The thermal expansion coefficient of the developed electrolytes matched well with commonly used electrode materials. These characteristics make GSEYD a promising candidate for use as an electrolyte material in SOFCs.