Electric field-assisted in situ fabrication of carbon/zirconia nanocomposites with tunable conductivity for electromagnetic interference shielding applications

• Published in: Composites. Part B, Engineering Engineering, 2022-11, Vol.246, p.110254, Article 110254
• Main Authors: Xu, Jingkun, Liu, Zetan, He, Shan, Sang, Guolong, Xie, Zhipeng, Xi, Xiaoqing
• Format: Article
• Language: English
• Subjects: Electromagnetic interference shielding; Field-assisted hot pressing; Graphene; Nanocomposites; Zirconia
• ISSN: 1359-8368; 1879-1069
• DOI: 10.1016/j.compositesb.2022.110254

Carbon/ceramic nanocomposites have been considered as ideal candidates for electromagnetic interference shielding (EMI) applications in harsh environments. However, the conventional fabrication methods of carbon/ceramic composites are often complicated, costly and time-consuming. Herein, by applying a DC electric field during hot pressing sintering, we realized the direct growth of graphene-like carbon nanosheets (GCNs) in zirconia ceramics during sintering, achieving in situ fabrication of GCNs/zirconia nanocomposites with both high EMI shielding effectiveness (>40 dB) and mechanical strength (>1000 MPa) in one step. In particular, we found that applying a DC electric field could significantly enhance the carburization during sintering, and GCNs are in situ formed at zirconia grain boundaries. When the initial electric field is constant, the amount of in situ formed GCNs could be controlled by simply adjusting the current density, resulting in the tunable electrical conductivity. These findings will provide new opportunities for both experimental and theoretical studies on carbon/ceramic EMI shielding materials and the DC electric field-assisted sintering technique. [Display omitted] •In situ growth of graphene-like carbon nanosheets (GCNs) in oxide ceramic is achieved under DC field.•The amount of GCNs can be controlled by adjusting current density, resulting in the tunable conductivity.•The nanocomposites exhibit superior electromagnetic interference shielding performance and mechanical strength.