Semiconductor heterojunction plays a pivotal role in photocatalysis. However, the construction of a heterojunction with a fine microstructure usually requires complex synthetic procedures. Herein, a pH-adjusted one-step method was employed to controllably synthesize Ag₄V₂O₇/Ag₃VO₄ heterojunction with a well-tuned 0D/1D hierarchical structure for the first time. It is noteworthy that the ordered stacking of vanadium oxide tetrahedron ( $V{O}_3^{-}$) guided by the pH value wisely realizes the in-situ growth of Ag₄V₂O₇ nanoparticles on the surface of Ag₃VO₄ nanorods. Furthermore, comprehensive characterization and calculation decipher the electronic structures of Ag₄V₂O₇ and Ag₃VO₄ and the formation of Z-scheme heterojunction, benefiting the visible light harvesting and carrier utilization. Such a new Ag₄V₂O₇/Ag₃VO₄ heterojunction exhibits remarkable photocatalytic activity and excellent stability. Complete degradation of Rhodamine B (RhB) can be achieved in 10 min by the Ag₄V₂O₇/ Ag₃VO₄ heterojunction under visible light irradiation, demonstrating an outstanding reaction rate of 0.35 min⁻¹ that is up to 84-fold higher than those of other silver vanadates. More importantly, this integration of synthesis technology and heterojunction design, based on the intrinsic crystal and electronic structures, could be inspiring for developing novel heterostructured materials with advanced performance.

Thermal barrier coatings (TBCs) can effectively protect the alloy substrate of hot components in aeroengines or land-based gas turbines by the thermal insulation and corrosion/erosion resistance of the ceramic top coat. However, the continuous pursuit of a higher operating temperature leads to degradation, delamination, and premature failure of the top coat. Both new ceramic materials and new coating structures must be developed to meet the demand for future advanced TBC systems. In this paper, the latest progress of some new ceramic materials is first reviewed. Then, a comprehensive spalling mechanism of the ceramic top coat is summarized to understand the dependence of lifetime on various factors such as oxidation scale growth, ceramic sintering, erosion, and calcium-magnesium-aluminium-silicate (CMAS) molten salt corrosion. Finally, new structural design methods for high-performance TBCs are discussed from the perspectives of lamellar, columnar, and nanostructure inclusions. The latest developments of ceramic top coat will be presented in terms of material selection, structural design, and failure mechanism, and the comprehensive guidance will be provided for the development of next-generation advanced TBCs with higher temperature resistance, better thermal insulation, and longer lifetime.

As an optical material, Y₂O₃ transparent ceramics are desirable for application as laser host materials. However, it is difficult to sinter and dense of Y₂O₃ hinders the preparation of high-quality optical ceramics via traditional processes. In this work, we use La₂O₃ as a sintering aid for fabricating high-transparency Y₂O₃ ceramics using a vacuum sintering process. It is demonstrated that the in-line optical transmittance of 15.0 at% La-doped Y₂O₃ at a wavelength of 1100 nm achieves a transmittance of 81.2%. A sintering kinetics analysis reveals that a grain-boundary-diffusion-controlled mechanism dominates the faster densification at high La³⁺ concentrations. It is also shown that both the mechanical and thermal properties of Y₂O₃ transparent ceramics are significantly improved upon the increase of La₂O₃ sintering additives. The results indicate that a La-doped Y₂O₃ transparent ceramic is a promising candidate for a laser host material.