Minimum Thermal Conductivity Research Articles

Computational study of the structural, mechanical, electronic, optical and thermal properties of BaLiX (X =P, As, Sb) perovskites

This study explores the structural, optical, mechanical, electronic, and thermal characteristics of ionic semiconductor compounds BaLiX (X = P, As, Sb) using Density Functional Theory (DFT). A comprehensive analysis of BaLiX (X = P, As, Sb) is conducted, proving that the estimated and observed lattice parameters coincide well and confirming mechanical stability through elastic stiffness constants. Electronic band structures reveal direct bandgap semiconductor properties with values of 0.70 eV, 0.30 eV, and 0.95 eV for BaLiP, BaLiAs, and BaLiSb, respectively, suggesting specific applications such as mid-infrared photodetectors, terahertz devices, and near-infrared sensors. Optical property analyses, including energy loss function, reflectivity, refractive index, and absorption coefficient, highlight the potential of these materials for optoelectronic and photovoltaic applications. Despite elastic anisotropy, optical anisotropy remains minimal. The materials exhibit potential for use as thermal barrier coatings (TBC) due to their comparatively lower Debye temperature (D), minimum thermal conductivity (Kmin) and lattice thermal conductivity (kph). Moreover, heat capacity calculations and thermal coefficient of expansion are also calculated.

Exploring high-performance environmental barrier coatings for rare earth silicates: A combined approach of first principles calculations and machine learning

RE2Si2O7 is promising materials for environmental barrier coating (EBC), but the vast phase space poses challenges for the screening of RE2Si2O7. It follows that a combined approach of first principles calculations and machine learning is proposed for this problem, with establishing a comprehensive database comprising β-, γ- and δ-RE2Si2O7 (RE=La–Lu, Y, Sc) and correlating their mechanical/thermal properties on structural characteristics. It is revealed the [O3Si–O–SiO3] structure and polyhedron distortion affect mechanical properties of RE2Si2O7, while criteria for selecting RE2Si2O7 with low thermal conductivity are identified, including complex crystal structures, chemical bond inhomogeneity, and strong non-harmonic lattice vibrations. Also, the machine learning model accurately predicts the coefficient of thermal expansion (CTE) and minimum thermal conductivity (λmin) of RE2Si2O7, with volume and mass variations identified as critical factors, respectively. This integrated approach efficiently screens RE2Si2O7 for EBC application and enables rapid assessments of their thermal properties.

Exploration of transition metal carbides TMCs (TM = V, Ti and Zr): mechanical, electronic structures and thermodynamic properties

The structural, mechanical, electronic, minimum thermal conductivity, tensile and thermodynamic properties of TMCs (M = Ti, V and Zr) have been investigated through first-principles calculations combination with QHA based on density-functional theory. The formation enthalpy, phonon spectrum and elastic constants emphasise that all TMCs are thermodynamically and mechanically stable. The elastic moduli of the VC are higher than the fourth group (TiC and ZrC). The strong covalent bonding between VC is the main reason for the high mechanical properties, while the ionic bonding of ZrC would explain for its low strength. Meanwhile, the weaker mechanical anisotropy of the TMCs favours a higher damage tolerance. Furthermore, the calculated minimum thermal conductivity in different directions of the TMCs demonstrated that is anisotropic. Finally the temperature dependence of thermodynamic parameters including volume, thermal expansion coefficient, bulk modulus and specific heat capacity at constant pressure is evaluated to be stable based on the QHA method.

Physical properties of novel double perovskite oxides Ba2XSbO6(X = P, As) by first-principle calculations

In this article, the structural, mechanical, electronic, optical, thermal, and thermodynamic properties of Ba2XSbO6 (X=P, As) double perovskite oxides were investigated by using first-principles calculations. The results show that the Goldsmith’s tolerance factor and octahedral factor of the two perovskites are in a stable range, the binding energy and formation energy are negative, and the elastic constants meet the Born-Huang stability criterion. These results suggest the stability of the two perovskite oxides. The mechanical property study indicates that Ba2XSbO6 (X=P, As) exhibits high bulk modulus and shear modulus. Poisson’s ratio (ν) and the elastic anisotropy index (A) suggest that they are anisotropic ductile materials. The electronic properties show that Ba2PSbO6 and Ba2AsSbO6 are indirect bandgap semiconductors with bandgap values of 2.130 eV and 1.596 eV, respectively. The optical properties show that Ba2XSbO6 (X=P, As) has excellent light absorption capacity in the range of 2.5–30 eV. Specifically, Ba2AsSbO6 has a higher absorption capacity for visible light compared to Ba2PSbO6. Thermodynamic properties show that the Debye temperature of the two perovskites is higher than 420 K, the melting points is higher than 1700 K, the minimum lattice thermal conductivities is close to 1, and the specific heat reaches the Dulong-Petit limit at about 700 K. This study shows that the double perovskite oxide Ba2XSbO6 (X=P, As) has important potential in the field of thermoelectricity and optoelectronics.

R32-Al5W: A new stable high-temperature alloy

Due to the high melting point, exceptional mechanical properties, and remarkable corrosion resistance exhibited by Al5W, researchers have conducted extensive research on the structural characteristics of Al5W. To identify the lowest energy structures and find new structures, a combination of particle swarm optimization and first-principles calculations was employed to identify energy-favorable Al5W structures under ambient pressure. The experimental P63 phase and the previously predicted R3¯c phase were identified. Notably, a new R32-Al5W phase was proposed. A comparative analysis on the structural stability, elastic, thermodynamic, and electronic properties of these three Al5W phases were conducted. The results indicate that R32-Al5W exhibits favorable thermodynamic stability, with a predicted bulk modulus close to that of R3¯c-Al5W. All the three Al5W phases demonstrate brittle behavior. The P63-Al5W phase displays larger shear anisotropy in the (010) and (001) planes, while the R32-Al5W phase shows greater shear anisotropy on the (100) plane compared to other two phases. Furthermore, employing Clarke’s and Cahill’s models, the minimum thermal conductivity of Al5W phases was predicted, revealing a magnitude order of P63 >R3¯c > R32. Our calculated melting points also conform to this trend.

Exceptional figure of merit achieved in boron-dispersed GeTe-based thermoelectric composites

GeTe is a promising p-type material with increasingly enhanced thermoelectric properties reported in recent years, demonstrating its superiority for mid-temperature applications. In this work, the thermoelectric performance of GeTe is improved by a facile composite approach. We find that incorporating a small amount of boron particles into the Bi-doped GeTe leads to significant enhancement in power factor and simultaneous reduction in thermal conductivity, through which the synergistic modulation of electrical and thermal transport properties is realized. The thermal mismatch between the boron particles and the matrix induces high-density dislocations that effectively scatter the mid-frequency phonons, accounting for a minimum lattice thermal conductivity of 0.43 Wm−1K−1 at 613 K. Furthermore, the presence of boron/GeTe interfaces modifies the interfacial potential barriers, resulting in increased Seebeck coefficient and hence enhanced power factor (25.4 μWcm−1K−2 at 300 K). Consequently, we obtain a maximum figure of merit Zmax of 4.0 × 10−3 K−1 at 613 K in the GeTe-based composites, which is the record-high value in GeTe-based thermoelectric materials and also superior to most of thermoelectric systems for mid-temperature applications. This work provides an effective way to further enhance the performance of GeTe-based thermoelectrics.

Behavior of Foreign Interstitial Hydrogen and Helium Atoms at Tungsten/Beryllium Interface from First-Principles Calculations

The behavior of foreign interstitial hydrogen and helium atoms and its effect on the physical properties of the tungsten/beryllium interface structure were computationally studied by first-principles calculations. Briefly, as part of our study of helium irradiation damage and hydrogen detention, the following properties were calculated: (1) the electronic properties of the tungsten/beryllium interface structure with a single interstitial hydrogen or helium atom and Hen vacancy or Hn vacancy complexes, and (2) the isotropy (polycrystalline) elastic modulus (bulk, torsion, Young’s modulus), anisotropy factor and minimum thermal conductivity of the previously described tungsten/beryllium interface systems. This study found that defect atoms are more likely to be concentrated in beryllium, but the tungsten layer is more sensitive to changes in mechanical properties caused by interstitial atoms. The ability of the beryllium vacancies to capture interstitial atoms is smaller than that of the tungsten vacancies. Based on the computational results, a preliminary assumption of the judgment of the tungsten/beryllium interface structure on the resistivity for plasma-facing materials is introduced. These computational studies provide a critical evaluation of the radiation resistivity and hydrogen retention of tungsten/beryllium interface materials. The calculated interface properties can be incorporated into radiation damage resistance property evaluation systems to develop and test tungsten-based composite materials.

First-Principles Study of the Structural, Mechanical, Electronic, and Thermodynamic Properties of AlCu2M (M = Ti, Cr, Zr, Sc, Hf, Mn, Pa, Lu, Pm) Ternary Intermetallic Compounds.

Based on the first principles, the structural stability, mechanical characteristics, electronic structure, and thermodynamic properties of AlCu2M (M = Ti, Cr, Zr, Sc, Hf, Mn, Pa, Lu, Pm) are investigated. The calculated results indicate that the AlCu2Pa crystal structure is more stable and that AlCu2Pa should be easier to form. All of the AlCu2M compounds have structural stability in the ground state. Elastic constants are used to characterize the mechanical stability and elastic modulus, while the B/G values and Poisson ratio demonstrate the brittleness and ductility of AlCu2M compounds. It is demonstrated that all computed AlCu2M compounds are ductile and mechanically stable, with AlCu2Hf having the highest bulk modulus and AlCu2Mn having the highest Young's modulus. AlCu2Mn has the highest intrinsic hardness among AlCu2M compounds, according to calculations of their intrinsic hardness. The electronic densities of states are discussed in detail; it was discovered that all AlCu2M compounds form Al-Cu and Al-M covalent bonds. Additionally, we observe that the Debye temperature and minimum thermal conductivity of AlCu2Mn and AlCu2Sc are both larger than those of others, indicating stronger chemical bonds and higher thermal conductivities, which is consistent with the elastic modulus results.

Comprehensive Utilization of Fossil Energy: Fabrication of Fire-Retardant Building Materials from Waste Plastic

As one of the most common fossil derivatives, plastics are widely used for their exceptional chemical stability, low density, and ease of processing. In recent years, there has been a significant increase in the production of waste plastics, coupled with a low recycling rate, resulting in serious environmental pollution. To enhance the use of waste plastics, this research synthesized flame-retardant materials from hypercrosslinked polystyrene with different molar fractions of flame retardants. Waste polystyrene foam was used as the raw material, while aniline, triphenylphosphine, and melamine were employed as flame-retardant additives. The flame-retardant additives were successfully doped into the porous skeleton structure of hypercrosslinked polystyrene through a chemical reaction or physical mixing to achieve in situ flame retardancy, and the materials were shaped by a phenolic resin prepolymer. Then, the samples were characterized in detail, and the results indicate that the addition of a flame retardant enhances the flame retardancy of the material. In addition, the material has excellent thermal insulation performance, with a minimum thermal conductivity of 0.04176 W/(m·K).

Computational insights of double perovskite X2CaCdH6 (X = Rb and Cs) hydride materials for hydrogen storage applications: A DFT analysis

Perovskite materials play a backbone role in materials science to investigate various applications including photocatalytic, photovoltaic, and hydrogen storage. Hydrogen storage is a modern technique to fulfill energy consumption and demands. We inspect the structural, hydrogen, electronic, optical, and thermodynamic properties of X2CaCdH6 (X = Rb and Cs) perovskite substances for hydrogen (H2) storage applications. The research shows substances have 225 Fm3m cubic natures and 40 atoms. The formation and cohesive energies of the examined structures show that X2CaCdH6 (X = Rb and Cs) substances may be produced and are thermodynamically stable. Electronic characteristics indicate that substances are semi-metallic, with correspondingly indirect bandgap Eg energies of 2.13 eV and 2.30 eV. The mechanical stability (Born stability), brittle (B/G = 1.22, 1.15 and α = 0.17, 0.18), hard (6.255, 5.481), and anisotropic (0.278, 0.171) of the X2CaCdH6 (X = Rb and Cs) perovskite substances are demonstrated by the examined elastic values. The Debye temperature ΘD (289.395, 320.837)K, melting temperature Tm (646.961, 650.714)K, acoustic velocities (vm, vl, vt) m/s, minimum thermal conductivity Kmin (0.63, 0.75) (W/mK), and Grüneisen parameter (18.121, 19.521) of substances are also computed by investigating their thermodynamic characteristics. Cs2CaCdH6 and Rb2CaCdH6 have gravimetric ratios of 1.39 wt% and 1.69 wt%, correspondingly. Our findings shed light on using double perovskites X2CaCdH6 (X = Rb and Cs) as a hydrogen (H2) storage substance.

A systematic first-principles investigation of the structural, electronic, mechanical, optical, and thermodynamic properties of Half-Heusler ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) for spintronics and optoelectronics applications.

This paper is the first to look at the structural, electronic, mechanical, optical, and thermodynamic properties of the ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) half-Heusler (HH) using DFT based first principles method. The lattice parameters that we have calculated are very similar to those obtained in prior investigations with theoretical and experimental data. The positive phonon dispersion curve confirm the dynamical stability of ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn). The electronic band structure and DOS confirmed that the studied materials ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) are direct band gap semiconductors. The investigation also determined significant constants, including dielectric function, absorption, conductivity, reflectivity, refractive index, and loss function. These optical observations unveiled our compounds potential utilization in various electronic and optoelectronic device applications. The elastic constants were used to fulfill the Born criteria, confirming the mechanical stability and ductility of the solids ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn). The calculated elastic modulus revealed that our studied compounds are elastically anisotropic. Moreover, ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) has a very low minimum thermal conductivity (Kmin), and a low Debye temperature (θD), which indicating their appropriateness for utilization in thermal barrier coating (TBC) applications. The Helmholtz free energy (F), internal energy (E), entropy (S), and specific heat capacity (Cv) are determined by calculations derived from the phonon density of states.

Towards the Optimization of Polyurethane Aerogel Properties by Densification: Exploring the Structure–Properties Relationship

The aerogel performance for industrial uses can be tailored using several chemical and physical strategies. The effects of a controlled densification on polyurethane aerogels are herein studied by analyzing their textural, mechanical, sound, optical, and thermal insulating properties. The produced aerogels are uniaxially compressed to different strains (30%–80%) analyzing the consequent changes in the structures and, therefore, final properties. As expected, their mechanical stiffness can be significantly increased by compression (until 55‐fold higher elastic modulus for 80%‐strain), while the light transmittance does not noticeably worsen until it is compressed more than 60%. Additionally, the modifications produced in the heat transfer contributions are analyzed, obtaining the optimum balance between density increase and pore size reduction. The minimum thermal conductivity (14.5%‐reduction) is obtained by compressing the aerogel to 50%‐strain, where the increment in the solid conduction is surpassed by the reduction of the radiative and gas contributions. This strategy avoids tedious chemical modifications in the synthesis procedure to control the final structure of the aerogels, leading to the possibility of carefully adapting their structure and properties through a simple method such as densification. Thus, it allows to obtain aerogels for current and on‐demand applications, which is one of the main challenges in the field.

Strong low-energy rattling modes enabled liquid-like ultralow thermal conductivity in a well-ordered solid

ABSTRACT Crystalline solids exhibiting inherently low lattice thermal conductivity (κL) are of great importance in applications such as thermoelectrics and thermal barrier coatings. However, κL cannot be arbitrarily low and is limited by the minimum thermal conductivity related to phonon dispersions. In this work, we report the liquid-like thermal transport in a well-ordered crystalline CsAg5Te3, which exhibits an extremely low κL value of ∼0.18 Wm−1K−1. On the basis of first-principles calculations and inelastic neutron scattering measurements, we find that there are lots of low-lying optical phonon modes at ∼3.1 meV hosting the avoided-crossing behavior with acoustic phonons. These strongly localized modes are accompanied by weakly bound rattling Ag atoms with thermally induced large amplitudes of vibrations. Using the two-channel model, we demonstrate that coupling of the particle-like phonon modes and the heat-carrying wave-like phonons is essential for understanding the low κL, which is heavily deviated from the 1/T temperature dependence of the standard Peierls theory. In addition, our analysis indicates that the soft structural framework with liquid-like motions of the fluctuating Ag atoms is the underlying cause that leads to the suppression of the heat conduction in CsAg5Te3. These factors synergistically account for the ultralow κL value. Our results demonstrate that the liquid-like heat transfer could indeed exist in a well-ordered crystal.

Effect of HPHT technology and Se doping on thermoelectric properties of In filled Fe doped CoSb3 materials

Skutterudite (CoSb3) is a kind of promising environment-friendly medium-temperature thermoelectric material. Indium-filled CoSb3 has been widely studied, but its bipolar effect, which is commonly generated between 600 and 700 K, seriously hinders the increase of Seebeck coefficient and zT value. The zT value not only directly reflects the overall thermoelectric performance of the material, but also reflects the thermoelectric conversion efficiency of the device. In this work, In filled and Fe, Se double doped CoSb3 materials were successfully prepared by high-temperature and high-pressure synthesis method (HPHT), with a significant shorten synthesis time of 30 mins for each sample. This research has shown that after Se doping via HPHT synthesis method, the bipolar effect of In-filled CoSb3 was significantly suppressed, thus the temperature limitations of electrical transport performance has been overcome. Through the further microstructure analysis, it was found that the crystal structure of sample In0.5Fe0.01Co3.99Sb11.91Se0.09 has the characteristics of multiple grain sizes and complex defect types. And these two microscopic morphological characteristics resulted in the sample obtaining a minimum lattice thermal conductivity of 0.94 Wm−1K−1 at a test temperature of 773.15 K. Through synergistic optimization of synthesis methods and element substitution, the maximum zT value of 1.21 of the sample In0.5Fe0.01Co3.99Sb11.91Se0.09 has been found at 773.15 K.

Mechanical Properties and Thermal Conductivity of Y-Si and Gd-Si Silicides: First-Principles Calculations

The traditional Si bonding layer in environmental barrier coatings has a low melting point (1414 °C), which is a significant challenge in meeting the requirements of the next generation higher thrust-to-weight ratio aero-engines. To seek new bonding layer materials with higher melting points, the mechanical properties of Y-Si and Gd-Si silicides were calculated by the first-principles method. Subsequently, empirical formulae were employed to compute the sound velocities, Debye temperatures, and the minimum coefficients of thermal conductivity for the YSi, Y5Si4, Y5Si3, GdSi, and Gd5Si4. The results showed that Y5Si4 has the best plasticity and ductility among all these materials. In addition, Gd5Si4 has the minimum Debye temperature (267 K) and thermal conductivity (0.43 W m−1 K−1) compared with others. The theoretical calculation results indicate that some silicides in the Y-Si and Gd-Si systems possess potential application value in high-temperature bonding layers for thermal and/or environmental barrier coating.

Enhancing the thermal cyclic reliability of salt-based shape-stabilized phase change materials by in-situ SiO2–C interconnectivity in rice husk carbon

Utilizing salt-based shape-stabilized phase change materials (ss-PCMs) for high-temperature thermal energy storage stands as a pivotal avenue in realizing carbon neutrality. However, the performance of ss-PCMs significantly deteriorates after thermal cycling. This study utilizes rice husk carbon (RHC) with an in-situ SiO2–C interconnected structure as the encapsulating material, along with expanded graphite (EG) and MgO, to encapsulate ternary chloride (TC). In this approach, RHC simultaneously acts as a thermal conductivity materials (TCM) and a ceramic supporting material (CCM). The results showed that this encapsulation method can effectively encapsulate up to 65% of TC. The 60 wt% TC-10 wt% RHC-10 wt% EG-20 wt% MgO sample named 60T/10R/10E/20M is considered a close to optimal formulation in terms of thermal conductivity and phase change enthalpy. This ss-PCM has a thermal conductivity of 8.86 W m−1 K−1, and phase change enthalpy of 153.6 J g−1. The ss-PCMs maintained shape stability even after 1000 cycles, with minimal mass loss and thermal conductivity degradation compared to the non-RHC-added ss-PCM. This study has prepared high performance and reliability thermal storage materials through a green and low-cost approach.

Electronic, optical, elastic, and thermal properties of the half-Heusler-derived Ti2FeNiSb2: A DFT study

The electronic, optical, elastic, and thermal transport properties of half-Heusler-derived (HHD) Ti2FeNiSb2 are comprehensively characterized via density functional theory. The stability of HHD Ti2FeNiSb2 is evaluated by the phonon dispersion, formation energy, and phase separation, and its elastic constants meet the mechanically stable conditions. HHD Ti2FeNiSb2 is predicted to be an indirect nonmagnetic semiconductor with a bandgap of 0.94 (PBE) eV and 1.75 (HSE06) eV. To further understand the electronic structures, the atomic orbital projection of the electronic band structure is systematically studied and discussed. The band structures and bandgap can be sensitively tuned by the strain. The calculated elastic and optical properties indicate that Ti2FeNiSb2 has good ductility and hardness, and the optical property calculations reveal its excellent potential for harvesting solar energy. Using the elastic properties, the minimum lattice thermal conductivity is evaluated by the Slack, Clarke, and Cahill models. Based on the Slack model, the lattice thermal conductivity is 5.93 W/mK at 300 K; this value is consistent with the experimental value.

Newly synthesized Pb-based 312 MAX phases M3PbC2 (M = Zr and Hf): A First-principles study

The MAX phases' unique mixture of ceramic and metallic features makes them appealing for various technological uses. Zr3PbC2 and Hf3PbC2, two Pb-based MAX phases, were recently synthesized experimentally. The physical properties, such as structural properties as well as electronic, mechanical, hardness, thermal, and lastly, the optical properties of M3PbC2 (M = Zr and Hf) have been investigated using density functional theory (DFT) and analogized with those of other 312 MAX phases. The optimized cell volume and computed lattice constants match the experimental values. The calculated band structure certifies the metallic character, and DOS calculations confirmed the dominant contribution to conductivity from the Zr-4d and Hf-5d states. The stiffness constant (Cij) proved the mechanical stability of these compounds. The mechanical behavior of the studied compounds was explored by calculating the elastic moduli, hardness parameters, and fracture toughness, which are also compared to those of the 312 MAX phases. The tightly bound M–C covalent bonds within the crystal give these compounds high stiffness. The Mulliken population (both atomic and bond) was calculated to explore the bonding characteristics within them and the Vickers hardness of the titled phases. The degree of elastic anisotropy present within phases has been analyzed by calculating different indices. The phonon dispersion curves and phonon DOS (PHDOS) were computed to check the dynamical stability of the phases. Thermodynamic potential functions were calculated from the PHDOS. The thermal parameters were also studied, including the Debye temperature, melting temperature, Grüneisen parameter, and minimum thermal conductivity (Kmin). A thorough computation and analysis of the vital optical constants was done to explore their potential in diverse fields. The titled compounds are suitable for use as thermal barrier coating (TBC) materials and coating materials to prevent solar heating.

Vacancy Suppression and Resonant Level Rendering Extraordinary Power Factor in Sn0.99In0.01Te/Tourmaline Composite.

SnTe, as a potential medium-temperature thermoelectric material, reaches a maximum power factor (PF)usually above 750K, which is not conducive to continuous high-power output in practical applications. In this study, PF is maintained at high values between 18.5 and 25µWcm-1K-2 for Sn0.99In0.01Te-xwt% tourmaline samples within the temperature range of 323 to 873K, driving the highest PFeng of 1.2Wm-1K-1 and PFave of 22.5µWcm-1K-2, over 2.5 times that of pristine SnTe. Such an extraordinary PF is attributed to the synergy of resonant levels and Sn vacancy suppression. Specifically, the Seebeck coefficient increases dramatically, reaching 88µVK-1 at room temperature. Meanwhile, by Sn vacancy suppression, carrier concentration, and mobility are optimized to ≈1019cm-3 and 740cm2V-1s-1, respectively. With the tourmaline compositing, Sn vacancies are further suppressed and the thermal conductivity simultaneously decreases, with the minimum lattice thermal conductivity of 0.9W m-1 K-1. Finally, the zT value ≈0.8 is obtained in the Sn0.99In0.01Te sample. The peak of the power output density reaches 0.89W cm-2 at a temperature difference of 600K. Such SnTe alloys with high and "temperature-independent" PF will offer an option for realizing high output power in thermoelectric devices.

Insight into the Physical Properties of the Chalcogenide XZrS3 (X = Ca, Ba) Perovskites: A First-Principles Computation

This study investigates the structural, mechanical, optical, thermal, and electronic properties of the ionic semiconducting materials XZrS3 (X = Ca, Ba) within the framework of density functional theory (DFT). Here, the elastic constants, modulus (bulk, shear, Young's), ratios (Pugh, Poisson) and elastic anisotropy for XZrS3 (X = Ca, Ba) are studied. Furthermore, the electronic, optical, and thermal properties for XZrS3 (X = Ca, Ba) are regenerated and designed using the values obtained with Cambridge Serial Total Energy Package (CASTEP) software. The calculated lattice parameters show excellent agreement with theoretical and experimental values. The elastic stiffness constants confirm the mechanical stability of both compounds. Although XZrS3 (X = Ca, Ba) is elastically anisotropic, it has little optical anisotropy. The electronic band structures of the material exhibit direct-bandgap semiconducting behavior, with values of 1.3 eV (CaZrS3) and 1.1 eV (BaZrS3) using the generalized gradient approximation (GGA), respectively, which is ideal for solar cell (0.9–1.56 eV) and optoelectronic device applications. Bandgap values of 1.9 eV and 1.6 eV are found for CaZrS3 and BaZrS3, respectively, using the Heyd–Scuseria–Ernzerhof HSE06 functional, which is consistent with previous theoretical and experimental bandgap results. The optical properties including dielectric function, refractive index, absorption coefficient, reflectivity, and loss function are characterized using the GGA of Perdew–Burke–Ernzerhof (GGA-PBE) and HSE06 methods and are discussed in detail. Because of the relatively low Debye temperature (D), thermal conductivity of the lattice (kph), and minimum thermal conductivity (Kmin), the studied materials can be used as thermal barrier coating (TBC) materials. The capacity of heat, Debye temperature, and thermal coefficient of expansion are all computed.