▎ 摘　　要

Implementation of layered structures with strong nanoscale optimized interfaces, enables engineering of materials with functional properties. In this work, anisotropic functional multi-layered structures are produced by integration of a thin hybrid inter-layer of graphene-augmented-nanofibers/alumina into alpha-alumina through an ex-situ strategy of precipitating the tailored hybrid from a solution. Spark plasma sintering was used to consolidate the layered structures at 1150 and 1450 degrees C under 75 and 50 MPa pressure. Raman spectroscopy suggests presence of C-H bonds and sp3 hybridization for the samples sintered at 1150 degrees C, while graphene structure is purified at the sintering temperature of 1450 degrees C. The multilayer structures demonstrate a high in-plane electrical conductivity which can be modulated, ranging from 300 to 1800 S m(-1) as a function of the interlayer thickness and the carbon content. A p-type conduction at room temperature and n-type down to 4 K in graphene-augmented nano-fillers was observed in Hall measurement. However, the multilayered systems display a p-type conduction in the entire temperature range. Hardness was preserved despite the high concentration of the graphene-augmented nano-fillers in the hybrid interlayer leaving a highest value of similar to 22 GPa. The results have the potential to fuel the development of functional electronic enclosures with additional functionalities such as electromagnetic interference shielding. (C) 2020 Elsevier Ltd. All rights reserved.