Single-source-precursor derived RGO/CNTs-SiCN ceramic nanocomposite with ultra-high electromagnetic shielding effectiveness

For the first time, single-source-precursors (SSPs) were synthesized through chemical modification of a commercial poly(methylvinyl)silazane with chemically bonded graphene oxide and carbon nanotube hybrids (GO/CNTs). After pyrolysis of warm-pressed and consolidated SSP-powders at 1000 degrees C in Ar, monolithic SiCN ceramic nanocomposites modified with in-situ thermally reduced GO/CNTs, namely RGO/CNTs-SiCN, were successfully obtained. The SSP-derived nanocomposite exhibits significantly enhanced dielectric properties if compared with that of a physically-blended-precursor derived reference material. Moreover, the SSP-derived RGO/CNTs-SiCN composite containing 15.0 wt% GO/CNTs in the feed possesses an electromagnetic shielding effectiveness of 67.2 dB with a sample thickness of 2.00 mm, which is the highest value among all the reported graphene-based composites with comparable thickness. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.