The advancement of communication technologies demands dielectric materials with superior performance characteristics, particularly low permittivity and minimal dielectric loss. This study investigates Ge⁴⁺-substituted willemite ceramics, including Zn₂Si_1-xGe_xO₄ (ZS-xGe, x=0 and 0.1) and Zn_1.8Si_1-yGe_yO_3.8 (ZS-yGe, y=0 to 0.3), synthesized via the conventional solid-state method. The non-stoichiometric design effectively suppresses the formation of ZnO. The intrinsic and extrinsic losses of the ZS-xGe ceramics are separated by a systematic comparative analysis of the dielectric losses in the terahertz band, and the extrinsic losses are fitted by the Drude term in the Lorentz-Drude dielectric response model. Consequently, ZS-yGe ceramics exhibit lower ε_r and significantly improved Q×f values across microwave to terahertz band. In ZnO-free ceramics, Ge⁴⁺ substitution enhances the ionic polarizability, the unit cell volume and the bond strain, increasing ε_r and Q×f values (decreasing intrinsic losses), and decreasing τ_f. The optimized Zn_1.8Si_0.9Ge_0.1O_3.8 ceramics demonstrate superior dielectric properties with ε_r = 6.66, Q×f = 225,500 GHz and τ_f = -60.0 × 10^-6℃^-1 at 12.45 GHz, and ε_r = 7.02, Q×f = 401,800 GHz at 1 THz. These novel ceramics are positioned as promising candidates for next-generation microwave and terahertz communication devices.

In this study, we propose grain boundary engineering and nanostructuring to enhance the thermo-electric performance of SnTe through tri-doping with Mn, Ge, and Bi. The synergistic effects on the band structure were analyzed through DFT calculations and validated through a series of doping experiments with each dopant. The nonstoichiometrically tri-doped sample exhibits a unique microstructure, characterized by Mn-Ge precipitates along the grain boundaries and coherently embedded nanostructures within the matrix. These microstructural features, combined with the effects of each dopant, synergistically enhanced the thermoelectric properties, yielding a maximum zT of 1.32 at 873 K. The thermoelectric generator exhibited a maximum output power of 661 μW at ΔT = 485 K, confirming its viability for mid-temperature thermoelectric applications.

Tuning the structure-activity of fillers and matrix is crucial for designing polymer-based dielectric capacitors with high energy storage performance. Up to date, how the fillers' structural characteristics (surface/interface configurations, dimensions, orientations etc.) contribute to the overall energy storage is far from unveiled. To this end, a combined filler-polymer dual-side design strategy is developed, which involves the DFT guidance for the electronic transport criteria for the designable synthesis of KNb₃O₈ fillers. Four different structural configurations are constructed, which are surface-modified with polydopamine (PDA) to fabricate the final composite films, i.e. PDA@KNb₃O₈/PVDF-P(VDF-HFP)-PMMA with particular orientations and arrangements, through a well-controlled solution casting method. Comprehensive structural and electrical investigations reveal that 1D/2D-orientated PDA@KNb₃O₈ fillers could obviously enhance the breakdown field and energy storage performance. The difference is that the 1D fillers more effectively improve the energy efficiency (up to 72%), while the 2D fillers more steadily achieve high energy density (U_e = 28.35 J/cm³) among the highest U_e reported for the composites. This work not only uncovers the structural origin of the electrostatic storage in inorganic-polymer composite films but also provides critical insights in designing high-energy-density film capacitors.

The exploitation of high-entropy rare-earth monosilicates (HEREMSs) with enhanced calcium-magnesium-aluminum-silicate (CMAS) corrosion resistance is vital for their potential applications as environmental barrier coatings (EBCs). Here, we present an inverse design strategy to explore HEREMSs with superior CMAS corrosion resistance. By high-throughput synthesis and dissolution experiments of equimolar 1-12-cation apatite powders at 1400 ℃, four optimized rare-earth elements, Lu, Yb, Er, and Nd, are determined to compositionally screen preferable high-entropy apatite with the lowest dissolution rate in CMAS melt, ultimately facilitating the inversely design of novel (Nd_2/15Er_3/5Yb_2/15Lu_2/15)₂SiO₅ (HEREMS-1). Further CMAS corrosion experiments have verified its superior CMAS corrosion resistance at temperatures up to 1500 ℃, exceeding the performance of previously reported EBC materials. Our work paves an alternative way for developing HEREMSs with exceptional CMAS corrosion resistance, making them highly suitable for future EBC applications.

Directional thermal transport materials enable anisotropic heat flow, thereby enhancing the efficiency of thermal management systems. These materials have found broad applications in aerospace, electronics, and automotive industries. Silicon carbide (SiC) based composites, with their exceptional properties including high modulus, thermal stability, and superior thermal conductivity, serve as an ideal structural material. Strategic manipulation over microstructure and composition enables directional thermal management, expanding applicability in thermal management and achieving structural-functional integration. By combining selective laser printing with precursor impregnation and pyrolysis (PIP), this work presents an innovative approach to fabricating thermally anisotropic C_f/SiC composites that integrate both structural and functional properties. The optimized composite (20% (in volume) chopped C_f) exhibited high fiber alignment (f_p = 0.7677) and pronounced thermal anisotropy, with thermal conductivities of 70.14 W/(m·K) perpendicular and 38.87 W/(m·K) parallel to the printing plane (anisotropy ratio: 1.8). This directional heat transport, enabled by fiber orientation and phonon scattering control, is critical for advanced thermal management. The composite also maintained good mechanical strength, exhibiting a flexural strength of (150.4 ± 9.8) MPa parallel to the printing plane, finalizing in a structural and functional integration.

To meet the demands of miniaturization and integration in modern electronic packaging, developing materials with low coefficient of thermal expansion (CTE) is essential to reduce thermal stress and enhance device reliability. In this study, the dense negative thermal expansion ceramic ScF₃ was prepared with a CTE of -8.86 × 10^-6/℃. The ScF₃ ceramic was cold sintered at 150 ^℃, exhibiting a low permittivity of 5.3 and a high quality factor (Q×f) of 14,700 GHz. By incorporating ScF₃ to the hexagonal boron nitride (BN) ceramic, the CTE of ScF₃-BN composite ceramic was adjusted to 3.36 × 10^-6/℃, establishing compatibility with silicon-based chips. And finite element simulations verified that ScF₃-BN composite significantly reduces thermal stress compared to Li₂MoO₄ or Al₂O₃ ceramics. Furthermore, this work demonstrates the potential of cold-sintered ScF₃ to regulate thermal expansion in packaging substrates, paving the way for improved performance in next-generation electronic devices.

Ultra-high temperature ceramics (UHTCs) exhibit ultra-high melting points and relatively high mechanical performance, making them ideal coating materials for extreme environment applications like hypersonic vehicles. Recently, novel design strategies of UHTCs coatings have been proposed, mainly including the composition and structural design. In this article, state-of-the-art approaches including multilayer and gradient UHTC coatings for enhanced mechanical and ablation resistance, surface engineering for the improvement of coating adhesion, materials and microstructural design for thermal insulation, laser ablation protection, and drag reduction were reviewed. Furthermore, advanced designing and fabrication techniques for UHTC coatings are also prospected, which can provide insights for the development of next-generation multi-functional UHTC coatings for harsh conditions.

Density Functional Theory (DFT)-derived electronic descriptors are key to accelerating the design of effective ORR/OER catalysts. The O 2p-band center, in particular, is a robust descriptor of catalytic activity in perovskite oxides. This study examines the O 2p-band center in Fe⁴⁺ perovskite-type layered oxides, focusing on the Ruddlesden Popper (RP) phases Sr₂FeO₄ and Sr₃Fe₂O₇, as well as the high-Tc superconductor YSr₂Cu₂FeO₈. The analysis emphasizes trends driven by compositional modifications. The O 2p-band centers of Sr_2-2xLa_2xFeO₄ and Sr_3-3xLa_3xFe₂O₇ (0 < x < 1) correlate linearly with the Fe oxidation state, and span a wide energy range (-1.2 eV to -4.7 eV with PBE+U; -1.9 eV to -4.7 eV with SCAN). Partial substitution of Fe with 3d transition metals (TM) in Sr₂Fe_7/8xM_1/8O₄ shifts the O 2p band center, with the more electronegative TMs bringing it closer to the Fermi level. RP-Sr₂FeO₄ exhibits remarkable tunability of the O 2p-band center, enabling the compositionally driven design of oxygen catalysts with potentially improved activity-stability balance. In contrast, YSr₂Cu₂FeO_7+δ (0 < δ < 1) shows no correlation between the O 2p-band center and Fe oxidation states, likely due to a change in Fe coordination from octahedral (δ = 1) to tetrahedral (δ = 0). The O 2p-center values (-0.9 eV to -1.3 eV with PBE+U; -1.5 eV to -2 eV with SCAN) suggest that YSr₂Cu₂FeO_7+δ could potentially catalyze the ORR/OER, though stability over operation time remains a challenge.

Defect engineering is a key strategy for optimizing the thermoelectric (TE) properties of PbTe-based materials, and investigating charged defects in PbTe grain boundaries (GBs) is crucial for understanding its thermoelectric properties. In this study, focusing the GBs, we perform a high-throughput investigation of the formation energies with various charged point (intrinsic and extrinsic) defects and their effects on the mechanical properties, the shear modulus. The GBs can facilitate the formation of the charged point defects (such as , ), indicating the accumulations of the defects within the GBs region. Such defect accumulation can strongly increase the phonon scatterings. Furthermore, charge defects within Te-PbTe GBs lower the shear modulus to <33.1 GPa, due to the weakening interactions between Pb-Te bonds. The soft bonds around GBs will induce the stronger anharmonicity and further suppress the lattice thermal conductivity. Employing the machine learning method, we establish the relationship between the shear modulus and physical descriptors, which can efficiently screen or design the various purposes of PbTe compounds. Our work bridges the gap in understanding charged defects at grain boundaries in PbTe-based thermoelectric materials and giving rise to the design methodology to achieve high promising thermoelectric performance through charged defect influenced mechanical properties.

The utilization of hybrid ion batteries (HIBs) effectively reduces the consumption of scarce Li resources and harnesses the synergistic effect of mixed ions to achieve performance comparable to that of lithium-ion batteries. However, there is currently a lack of anode materials that possess both high safety and excellent performance for HIBs. Herein, we present a novel structure of enclosed hard carbon nanotubes (HCNTs) doped with high levels of nitrogen and oxygen as anodes for HIBs. When utilized in Li-Na-K HIBs, they exhibit superior reversible capacity (440.1 mA·h·g^-1 at 100 mA/g) and enhanced rate performance (327.7 mA·h·g^-1 at 1 A/g) compared to single alkali metal ion batteries. These improvements can be attributed to the design of a one-dimensional structure that features highly doped hard carbon, which significantly enhances carrier transport. Furthermore, first-principles calculations reveal the synergistic effect of hybrid ions in nitrogen-doped hard carbon nanotubes, enhancing the ion adsorption stability in the carbon layer. This study introduces a substantial anode material for HIBs and expands the scope from binary to ternary HIB systems.