Nanostructured Hybrid Powders Based on Zirconia and Oxygen-Free Graphene—New Raw Materials for Fine-Grained Ceramics
摘要
Nanocomposites based on graphene and zirconia play an important role in the development and production of materials in demand in a wide range of technologies for the production of innovative materials for oxygen sensors, lithium-ion battery electrodes, catalysts, implants, solid oxide fuel cells, and electronic devices. The paper presents the results of a study covering a chain of successive processes: obtaining powders of graphene-containing nanostructured composites, characterizing their phase composition and morphology, sintering the resulting compositions by hot pressing, vacuum sintering, and spark plasma sintering, and comparative analysis of the microstructure of the obtained model ceramic samples. All the resulting ceramics consisted of stoichiometric monoclinic baddeleyite ZrO2. Distinctive features of the ceramics obtained by spark plasma sintering were a high relative density of 98% and a layered grain structure. The main result of the study can be considered the fact that graphene-zirconia nanostructured powder composites synthesized by the proposed method are promising for obtaining dense fine-grained ceramics. However, due to their unique nanostructure of the initial powders, they require the development of special modes and technological approaches to sintering to achieve high density and other unique characteristics.