High Temperature Oxidation Behaviors of BaO/TiO2 Binary Oxide-Enhanced NiAl-Based Composites

High temperature lubricating composites have been widely used in aerospace and other high-tech industries. In the actual application process, high temperature oxidation resistance is a very importance parameter. In this paper, BaO/TiO2-enhanced NiAl-based composites were prepared by vacuum hot-press sintering. The oxidation resistance performance of the composites at 800 °C was investigated. The composites exhibited very good sintered compactness and only a few pores were present. Meanwhile, the composite had excellent oxidation resistance properties due to the formation of a dense Al2O3 layer which could prevent further oxidation of the internal substrate; its oxidation mechanism was mainly decided by the outward diffusion of Al and the inward diffusion of O. The addition of BaO/TiO2 introduced more boundaries and made the Kp value increase from 1.2 × 10−14 g2/cm4 s to 3.3 × 10−14 g2/cm4 s, leading to a slight reduction in the oxidation resistance performance of the composites—although it was still excellent

<i>In Situ</i> Fabrication of Bi₂WO₆/MoS₂/RGO Heterojunction with Nanosized Interfacial Contact via Confined Space Effect toward Enhanced Photocatalytic Properties

Heterojunction photocatalysts with nanosized interfacial contact possess excellent photocatalytic performance due to special natures such as shortening carriers transfer distance and expanding interfacial contact areas. Herein, the heterostructured interface with nanosized contact areas on Bi₂WO₆/MoS₂/RGO (BMG) is obtained successfully. Bi₂WO₆ nanocrystals are anchored on MoS₂/RGO (MG) substrate in a ternary composite. The confined space effect of MG two-dimensional material restricts the growth of Bi₂WO₆, which endows a heterojunction with nanosized interfacial contact. This kind of nanoscale heterojunction promotes interfacial carriers transfer and separation, leading to significantly enhanced photocatalytic performance of as-fabricated BMG compared to pure Bi₂WO₆. The present work provides a new understanding into design and fabrication of a novel heterojunction photocatalyst with nanosized interfacial contact by confined space effect