Transition metal nitride (TMN) films with excellent hardness and lubricating performance are versatile low dimension materials, which are widely used in various fields including industries, transportation, aerospace, and so on. This paper introduces one film design strategy and provides a review of the mechanisms for strengthening and lubricating nitride films. The design strategy refers to two aspects which determine the structures, the performance, the components, and the chemical constitutions of nitride films The strengthening mechanisms of nitride films are then illuminated in detail, including the solid solution effect, the grain size effect, the secondary phase effect, the stress or stress field effect, the template effect, and the valence electron concentration effect. Five lubricating mechanisms are next summarized, including the easy-shear nature, the tribo-chemical reactions, the lubricious fluorides, the textured contact surface, and the synergistic effect. This paper aims to give a comprehensive introduction for understanding the mechanisms of strengthening and lubrication of nitride films for students and researchers, as well as to understand the current research progress in nitride films for exploring research gaps.

CO₂ photoreduction technology offers significant potential for addressing energy and environmental challenges, though its practical application is hindered by insufficient photo-absorption and rapid carrier recombination. Herein, we constructed the WO₃/In₂S₃ S-scheme heterojunction through hydrothermal assembly of two-dimensional WO₃ nanosheets and scale-like In₂S₃ nanoflakes. Systematic characterization via XRD, XPS, SEM, and TEM verified the successful preparation of hierarchical nanostructures with optimized interfacial contact in the WO₃/In₂S₃ composites. UV-Vis DRS analysis showed that the photo-absorption range of the catalyst was significantly widened. Photoelectrochemical investigations (EIS, TPR, PL, and LSV) revealed enhanced carrier separation efficiency and reduced recombination kinetics in the heterojunction system. The optimized WO₃/In₂S₃ (WI-60) catalyst had a CO evolution efficiency of 55.14 μmol·g⁻¹ under the UV-Vis light, representing a 3.9-fold enhancement over the pure In₂S₃ (14.08 μmol·g⁻¹). Mechanistic studies through the XPS and band-structure analysis confirmed the establishment of an S-scheme carrier’ transfer pathway, which simultaneously preserved strong redox potentials and promoted the separation process of carriers. This research provides a validated strategy for developing efficient S-scheme photocatalytic systems for solar fuel generation.

Al2O3/epoxy resin composite materials were prepared with alumina as filler in this paper, and the effects of particle size and added quantity of Al2O3 powers on the thermal conductivity of the composites have been investigated. The results show that, thermal conductivity of the composites increases with the increase of the added quantity of Al2O3 powders, and suitable particle size of alumina filler could help to form heat conductive chain which can improve the thermal conductivity of the composites effectively. The thermal conductivity could reach 0.48 W/(m•K), which is five times than that of pure epoxy resin, when the amount of alumina powders is 60% and its mean particle size is 100µm.