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[Display omitted] • The strategy on high throughput first principles calculations is introduced. • The application of high throughput first principles calculations on prediction of new ceramics is summarized. • The perspective of high throughput first principles calculations on high performance ceramics is discussed. Recent technical progress in the industry has led to an urgent requirement on new materials with enhanced multi-properties. To meet this multi-property requirement, the materials consisting of three and more elements have attracted increasing attention. However, facing to the nearly unknown huge multi-component materials system, the traditional trial and error method cannot provide sufficient data efficiently. Therefore, an efficient material innovation strategy is significant. The first-principles calculation based on the density functional theory is a powerful tool for both the accurate prediction of material properties and the identification of its underlying thermodynamics and dynamics. At the same time, the advances of computational methods and computer calculation abilities that are orders of magnitude faster than before make the high throughput first-principles calculations popular. At present, the simulation-assisted material design has become a main branch in the material research field and a great many successes have been made. In this article, the advances of the high throughput first-principles calculations are reviewed to show the achievements of the first-principles calculations and guide the future directions of its applications in ceramics. [ABSTRACT FROM AUTHOR]

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 Gd2Zr2O7coatings 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.

Various excellent properties of rare earth zirconate and stannate pyrochlores are close related with their native point defects. First-principles calculations are performed to systematically investigate the point defect mechanism and the oxygen diffusion behavior of A 2 B 2 O 7 (A =La, Ce, Pr, Nd, Pm, Sm, Eu, Gd; B =Zr, Sn). The possible defect complexes and their associated reactions under stoichiometric and nonstoichiometric conditions are explored. The O Frenkel pairs are the most stable defect structure in stoichiometric zirconates, whereas the cation antisite defects are the predominant one in stoichiometric stannates. In the case of B O 2 excess zirconates and stannates, the B A cation antisite defect with the A vacancy and/or the oxygen interstitial is energetically favorable, whereas the A B antisite defect together with the oxygen vacancy and/or the A interstitial is preferable under the A 2 O 3 excess condition. Meanwhile, the maximum point defect concentrations of zirconates are much higher than those of stannates. Furthermore, the oxygen migration barriers are similar in these compounds, ranging in 0.68 eV∼ 0.80 eV. The predicted point defects and oxygen diffusion mechanisms play the critical role in their engineering applications and are expected to guide the future property improvement of pyrochlores through the control of point defects and/or composition. [ABSTRACT FROM AUTHOR]

Searching for new materials with extra low thermal conductivities is significant in numerous fields like thermal barrier coatings and thermoelectric devices. Traditional multiple-component design has successfully reduced the thermal conductivity, but it also dramatically increases the complexity of manufactural technologies and the risk of material failures. In this work, a specific category known as ABO4scheelites that with both simple crystal structure and the structural signature of the low lattice thermal conductivity is explored. High-throughput calculations are employed to screen for the materials with the targeted performance by multi-dimensional mechanical/thermal property criteria and a database of 46 stable scheelites is constructed. Seven scheelites with both ultra-low thermal conductivities (<1.2 W/(m∙K)) and quasi-ductility are predicted to be novel thermal insulation materials. Low thermal conductivities prefer the scheelites with large valence disparity between “A” and “B” cations and/or small ionic radius ratio. The adopted strategy starting from the structural fingerprint and the data-driven material selection is expected to be a reference of future structural and functional ceramics design.

Perovskite stannates are promising semiconductors that are widely used in optoelectronic devices. Here, the composition dependent intrinsic point defects of stannate perovskites A SnO 3 (A = Ca, Sr, Ba) are studied by first-principles calculations. The preferences of defects under stoichiometric and nonstoichiometric conditions are unsealed, meanwhile the charge states of each intrinsic defect varying with the change of electron Fermi energy are clarified. For stoichiometric BaSnO 3 and SrSnO 3 , the Schottky defect complexes are predicted as the most stable defect structure, while the antisite defect complexes are the most stable one in CaSnO 3. In nonstoichiometric A SnO 3 , excessive A O is beneficial to the formation of oxygen vacancies and A -Sn antisite defects in all A SnO 3 ; while the Ca interstitial is another major defect existing in CaSnO 3. In the case of SnO 2 excess, the predominant defects are the Sn- A antisite defects and A vacancies. Since the functionality of these perovskite oxides is closely related to the types and concentrations of their point defects, the present results are expected to guide the future experiments to optimize the function of the perovskite oxides by tailoring the intrinsic defects through controlling the composition of A O and SnO 2. [ABSTRACT FROM AUTHOR]