Near-Infrared Trapping by Surface Plasmons in Randomized Platinum-Ceramic Metamaterial for Thermal Barrier Coatings.

As the operation temperature of next generation gas turbine is targeted to be 1800 °C toward a higher efficiency and lower carbon emission, the near-infrared (NIR) thermal radiation becomes a major concern for the durability of the metallic turbine blades. Although thermal barrier coatings (TBCs) are applied to provide thermal insulations, they are translucent to the NIR radiation. It is a major challenge for TBCs to achieve optically thick with limited physical thickness (usually < 1 mm) for effectively shielding the NIR radiation damage.

Theoretical insights into the Peierls plasticity in SrTiO ceramics via dislocation remodelling.

An in-depth understanding of the dislocations motion process in non-metallic materials becomes increasingly important, stimulated by the recent emergence of ceramics and semiconductors with unexpected room temperature dislocation-mediated plasticity. In this work, local misfit energy is put forward to accurately derive the Peierls stress and model the dislocation process in SrTiO ceramics instead of the generalized stacking fault (GSF) approach, which considers the in-plane freedom degrees of the atoms near the shear plane and describes the breaking and re-bonding processes of the complex chemical bonds. Particularly, we discover an abnormal shear-dependence of local misfit energy, which originates from the re-bonding process of the Ti-O bonds and the reversal of lattice dipoles.

Ultra-dense dislocations stabilized in high entropy oxide ceramics.

Dislocations are commonly present and important in metals but their effects have not been fully recognized in oxide ceramics. The large strain energy raised by the rigid ionic/covalent bonding in oxide ceramics leads to dislocations with low density (∼10 mm), thermodynamic instability and spatial inhomogeneity. In this paper, we report ultrahigh density (∼10 mm) of edge dislocations that are uniformly distributed in oxide ceramics with large compositional complexity.

Diffused Lattice Vibration and Ultralow Thermal Conductivity in the Binary Ln-Nb-O Oxide System.

In the pursuit of low thermal conductivity materials for thermal management, one always tries to increase the material entropy by increasing the number of components in the materials to scatter heat-carrying phonons. However, it also drastically increases the technological complexity to synthesize materials with the target complex composition. Here, a material family is presented with simple composition Ln NbO , which only contains binary oxides of Ln O (Ln = Dy, Er, Y, Yb) and Nb O .