A green fabrication and variable temperature electromagnetic properties for thermal stable microwave absorption towards flower-like Co3O4@rGO/SiO2 composites. (1st June 2019)

• Record Type: Journal Article
• Authors: Ma, Junru; Shu, Jincheng; Cao, Wenqiang; Zhang, Min; Wang, Xixi; Yuan, Jie; Cao, Maosheng
• Is Part Of: Composites. Number 166(2019)
• Page Start: 187
• Page End: 195
• Publication Date: 2019-06-01
• Subjects: Flower-like Co3O4 -- rGO -- Graphene hybrids -- Electromagnetic properties -- Microwave absorption; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2018.11.119
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: High efficiency and thermal stability are two key factors of ideal electromagnetic attenuation materials, which are becoming desired owing to more complex modern service environment. Herein, a new type of high-temperature microwave absorber, flower-like Co3 O4 @rGO/SiO2 composite is synthesized by a generic and green fabrication route. It possesses stable microwave absorption (MA) performance in the temperature range from 353 K to 473 K. Particularly, the optimal reflection loss (RL) reaches −52.6 dB with thickness of 1.78 mm at the temperature of 353 K, and maximum bandwidth (RL ≤ −10 dB) of samples can cover the entire X-band (8.2–12.4 GHz) at the thickness of ∼2.00 mm. The excellent high-temperature MA performance can be ascribed to the synergistic effect of the introduced magnetic loss and conduction loss, as well as the multiple polarizations loss of three-dimensional (3D) hierarchical structures. Our work confirms that 3D hierarchical Co3 O4 @rGO/SiO2 sample can provide a novel pathway for designing high-temperature microwave absorbers in the future. Graphical abstract: Image 1 Highlights: The Co3 O4 flowers are implanted on the rGO to form 3D conduction networks. The complex dielectric constants present temperature dependence at elevated temperature. The evolution behavior of microwave attenuation is studied with the increasing temperature. Compared to other materials, the Co3 O4 @rGO/SiO2 samples possess the best high-temperature MA performance. The high-temperature microwave attenuation mechanism is discussed in detail.