High-entropy rare-earth (RE) disilicates are promising next-generation thermal/environmental barrier coating (T/EBC) materials. However, their resistance to calcium–magnesium–aluminosilicate (CMAS) corrosion and the underlying mechanisms remain insufficiently understood and require further improvement. This study aims to systematically investigate the CMAS corrosion behavior and predictive lifetime assessment of designed stoichiometric (Er_1/4Y_1/4Lu_1/4Yb_1/4)₂Si₂O₇ and non-stoichiometric (Er_1/6Tm_1/6Y_1/15Gd_1/15Lu_4/15Yb_4/15)₂Si₂O₇. The incorporation of Tm and Gd, characterized by their distinct ionic radii, is designed to enhance their phase stability. Mechanistic analysis reveals that lattice distortion induced by multication doping suppresses CMAS infiltration, while the introduction of larger-radius RE³⁺ ions promotes Ca²⁺ depletion in the CMAS melt, reducing its corrosive activity. A temperature-dependent transition in corrosion mechanisms is also elucidated. Thermodynamic–kinetic competition dominates at 1300 °C, whereas a dissolution–reprecipitation mechanism prevails at 1500 °C due to accelerated ion diffusion. Furthermore, an innovative extended Kalman filter (EKF) model is developed, enabling highly accurate prediction of the long-term corrosion depth and rate at 1300 °C, with an error of less than 3%. The experimental results demonstrate that both materials exhibit exceptional CMAS corrosion resistance, reducing the corrosion depth by approximately 70% compared with single-component RE₂Si₂O₇. This work not only clarifies the corrosion mechanisms and compositional design principles of high-entropy rare-earth disilicates but also provides a novel methodology for predictive lifetime assessment, advancing the development of next-generation T/EBC systems.

This review aims to establish general guidelines for designing highly active high-entropy materials (HEMs) with respect to lattice choice, component selection, and samorphological design, leading to the optimization of reaction kinetics and catalytic activity. HEMs have shown superior catalytic performance in hydrogen and oxygen evolution reactions because of their high-entropy structure of multielement random mixing, tailored chemical compositions, and tunable functional characteristics. However, the catalytic applications of HEMs are limited by structural instability, limited catalytic efficiency, and low conductivity, as well as their inherently complex and poorly controlled surface configurations. This review briefly introduces the characteristics of HEMs, highlighting their potential as electrocatalysts, which stems from their unique thermodynamic properties resulting from the collective interactions of multiple elements in the lattice. Then, approaches for enhancing the performance of HEMs are discussed, including composition selection, strain engineering, defect introduction, morphology control, support use, and the role of computational methods, particularly in guiding composition selection. Unlike prior reviews focusing on individual aspects of HEMs, this review systematically integrates computational-guided composition screening, defect engineering, strain modulation, and morphological control with thermodynamic-kinetic stability analysis, offering a holistic design framework that bridges multi-element synergy, surface optimization, and electronic structure tuning for practical electrocatalysis. Additionally, the discussion of stability is grounded in the thermodynamic principles of high entropy and the kinetics of slow diffusion. Finally, insights into challenges and prospects, including in situ characterization techniques, emerging computational methods, and scalability, are outlined to guide future advanced design strategies and fabrication technologies.

In hydrogen-fueled gas turbines, protons are more likely to penetrate the ceramic layer of thermal barrier coating (TBC) system and eventually reach the metallic bond coat. The knowledge about the atomic mechanism of proton migration in the ceramic layer of TBCs is important to evaluate the feasibility of using current TBCs in hydrogen-fueled gas turbines. In this work, tetragonal zirconia (T-ZrO₂) and yttria-stabilized tetragonal zirconia (T-YSZ) are focused on, and the configurations, formation energies, and migration of hydrogen defects are studied. The orientation of O–H bond is related to the length of Zr–O bond. This characteristic orientation leads to the differentiation of proton migration paths from the cubic phase and further results in the anisotropy of proton migration. Moreover, the isolated Y atom and Y–oxygen vacancy (V_O)–Y triple are introduced into the T-ZrO₂ supercell to investigate their impacts on proton migration. The former has a limited impact, while the oxygen vacancy has a significant trapping effect on protons. This trapping effect is attributed to changes in the local characteristics (especially the electronic properties) of O atoms near V_O due to lattice distortion. These findings provide critical insights into the proton migration mechanisms in TBCs, which are essential for optimizing TBCs for hydrogen-fueled gas turbine applications.

Magnesium-based hydrogen storage materials are promising candidates for hydrogen storage due to their high storage density and environmentally friendly properties. However, the high dehydrogenation enthalpy change (approximately 75 kJ/mol H₂) and high dehydrogenation temperature (573 K at 0.1 MPa) of MgH₂, limits the engineering application of Mg/MgH₂ as a hydrogen storage material. This work reviews the prediction models and methods of enthalpy changes for hydriding/dehydriding (H/D) reactions in order to find out the ideas and ways to reduce them. The mechanism behind the improvement methods mainly includes two aspects, weakening Mg-H bond and compensating heat of reaction. Proceed from this, the experimental methods and enthalpy data as well as calculated values of enthalpy changes were compared systematically. Elements such as Ti, Nb, V, etc., with a small electronegativity difference compared to Mg, can reduce the hydrogenation and dehydrogenation enthalpy changes by forming strong Metal-H or Metal-Mg bonds. In addition, this review concludes with an outlook on the remaining challenge issues and prospects.

RE₂Si₂O₇ is promising materials for environmental barrier coating (EBC), but the vast phase space poses challenges for the screening of RE₂Si₂O_7. 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 [O₃SiOSiO₃] 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 (λ_min) 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.

The atomic structural features and the mechanical properties of amorphous silicoboron carbonitride ceramics with 13 different compositions in the Si–BN–C phase diagram are investigated employing ab-initio calculations. Both chemical bonds and local structures within the amorphous network relate to the elemental composition. The distribution of nine types of chemical bonds is composition-dependent, where the B–C, Si–N, Si–C, and B–N bonds hold a large proportion for all compositions. Si prefers to be tetrahedrally coordinated, while B and N prefer sp²-like trigonal coordination. In the case of C, the tetrahedral coordination is predominant at relatively low C contents, while the trigonal coordination is found to be the main feature with the increasing C content. Such local structural characteristics greatly influence the mechanical properties of SiBCN ceramics. Among the studied amorphous ceramics, SiB₂C₃N₂ and SiB₃C₂N₃ with low Si contents and moderate C and/or BN contents have high elastic moduli, high tensile/shear strengths, and good debonding capability. The increment of Si, C, and BN contents on this basis results in the decrease of mechanical properties. The increasing Si content leads to the increment of Si-contained bonds that reduce the bond strength of SiBCN ceramics, while the latter two cases are attributed to the raise of sp²-like trigonal configuration of C and BN. These discoveries are expected to guide the composition-tailored optimization of SiBCN ceramics.

Orthorhombic perovskite oxides are studied by high-throughput first-principles calculations to explore new thermal barrier coating (TBC) materials with low thermal conductivities. The mechanical and thermal properties are predicted for 160 orthorhombic perovskite oxides. The average atomic volume is identified as a possible predictor of the thermal conductivity for the perovskite oxides, as it has a good correlation with the thermal conductivity. Five compounds, i.e., LaTmO₃, LaErO₃, LaHoO₃, SrCeO₃, and SrPrO₃, having thermal conductivities under 1 W·m^–1·K^–1 and good damage tolerance, are proposed as novel TBC materials. The obtained data are expected to inspire the design of perovskite oxide-based TBC materials and also support their future functionality investigations.

Gadolinium zirconate (GZ) is a promising candidate for next-generation thermal barrier coating (TBC) materials. Its corrosion resistance against calcium–magnesium–alumino–silicate (CMAS) needs to be further increased for enhancing its in-service life. As the Gd element plays an important role in the CMAS resistance, three GZ coatings (GZ-0.75, GZ-1.0, and GZ-1.2) with different Gd/Zr atomic ratios are designed and deposited by laser enhanced chemical vapor deposition (LCVD) in this work. It is found that the generated Gd-apatite in GZ-1.2 would block micro-cracks inside the column structure and the inter-columnar gap more efficiently. Thus, the CMAS penetration rate (5.2 μm/h) of GZ-1.2 decreases over 27% comparing with GZ-1.0 and GZ-0.75, which is even lower than the Gd₂Zr₂O₇ coatings fabricated by electron-beam physical vapor depositions (EB-PVDs). This work provides a feasible way to adjust the coating’s corrosion resistance and may guide the development of future coating for long in-service life.