Nanocellulose-MXene Biomimetic Aerogels with Orientation-Tunable Electromagnetic Interference Shielding Performance

Zhihui Zeng; Changxian Wang; Gilberto Siqueira; Daxin Han; Anja Huch; Sina Abdolhosseinzadeh; Jakob Heier; Frank Nüesch; Chuanfang John Zhang; Gustav Nyström

doi:10.1002/advs.202000979

Nanocellulose-MXene Biomimetic Aerogels with Orientation-Tunable Electromagnetic Interference Shielding Performance

Adv Sci (Weinh). 2020 Jun 28;7(15):2000979. doi: 10.1002/advs.202000979. eCollection 2020 Aug.

Authors

Zhihui Zeng¹, Changxian Wang², Gilberto Siqueira¹, Daxin Han³, Anja Huch¹, Sina Abdolhosseinzadeh^{4

5}, Jakob Heier⁴, Frank Nüesch^{4

5}, Chuanfang John Zhang⁴, Gustav Nyström^{1

6}

Affiliations

¹ Laboratory for Cellulose & Wood Materials Swiss Federal Laboratories for Materials Science and Technology (Empa) Dübendorf 8600 Switzerland.
² School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore.
³ Department of Information Technology and Electrical Engineering Swiss Federal Institute of Technology in Zurich (ETH Zürich) Zürich 8092 Switzerland.
⁴ Laboratory for Functional Polymers Empa Dübendorf 8600 Switzerland.
⁵ Institute of Materials Science and Engineering Swiss Federal Institute of Technology Lausanne (EPFL) Lausanne 1015 Switzerland.
⁶ Department of Health Science and Technology ETH Zürich Schmelzbergstrasse 9 Zürich 8092 Switzerland.

Abstract

Designing lightweight nanostructured aerogels for high-performance electromagnetic interference (EMI) shielding is crucial yet challenging. Ultrathin cellulose nanofibrils (CNFs) are employed for assisting in building ultralow-density, robust, and highly flexible transition metal carbides and nitrides (MXenes) aerogels with oriented biomimetic cell walls. A significant influence of the angles between oriented cell walls and the incident EM wave electric field direction on the EMI shielding performance is revealed, providing an intriguing microstructure design strategy. MXene "bricks" bonded by CNF "mortars" of the nacre-like cell walls induce high mechanical strength, electrical conductivity, and interfacial polarization, yielding the resultant MXene/CNF aerogels an ultrahigh EMI shielding performance. The EMI shielding effectiveness (SE) of the aerogels reaches 74.6 or 35.5 dB at a density of merely 8.0 or 1.5 mg cm^-3, respectively. The normalized surface specific SE is up to 189 400 dB cm² g^-1, significantly exceeding that of other EMI shielding materials reported so far.

Keywords: EMI shielding; MXenes; aerogels; cellulose nanofibrils; lightweight materials.