Ultralight and ordered lamellar polyimide-based graphene foams with efficient broadband electromagnetic absorption. (10th March 2022)

• Record Type: Journal Article
• Authors: Zhang, Yawei; Li, Shuangshuang; Tang, Xinwei; Fan, Wei; Lan, Qianqian; Li, Le; Ma, Piming; Dong, Weifu; Wang, Zicheng; Liu, Tianxi
• Is Part Of: Journal of materials science & technology. Volume 102(2022)
• Page Start: 97
• Page End: 104
• Publication Date: 2022-03-10
• Subjects: Polyimide -- Graphene -- Foam -- Ordered lamellar structure -- Microwave absorption; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2021.07.011
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: Ordered lamellar polyimide-based graphene foam has been constructed. More lamellar interfaces are formed inside the foam per unit volume. Lamellar porous structure promotes the layer-by-layer dissipation for incident EMW. Microwave absorption can be adjusted via controlling microstructure of the foam. Abstract: The development of high-performance microwave absorption materials with strong absorption capacity and broad bandwidth is highly desirable in the field of electromagnetic pollution protection. Herein, ultralight polyimide-based graphene foam with ordered lamellar structure is precisely designed and controllably constructed by bidirectional freezing process. More lamellar interfaces formed inside the foam per unit volume effectively facilitate the layer-by-layer dissipation for the vertical incident electromagnetic waves, thereby endowing the foam with efficient broadband electromagnetic absorption performance. More importantly, electromagnetic absorption performance can be controllably adjusted by optimizing impedance distribution and microstructure of skeletons. As a result, the optimized foam with an ultralow density of 9.10 mg/cm 3 presents a minimum reflection loss value of −61.29 dB at 9.25 GHz and an effective absorption bandwidth of 5.51 GHz (7.06–12.57 GHz, covering the whole X band) when the thickness is 4.75 mm. Graphical Abstract: Image, graphical abstract