Tunable Electromagnetic Interference Shielding Ability in a One-Dimensional Bagasse Fiber/Polyaniline Heterostructure

Abstract

Development of highly efficient electromagnetic interference (EMI) shielding materials with tunable properties is essential for the modern electronics industry against severe electromagnetic pollution. Herein, a series of novel heterostructured bagasse fiber/polyaniline (BF/PANI) composites are successfully synthesized via a facile in situ polymerization method and both their EMI shielding effectiveness (SE) and mechanisms were analyzed experimentally and theoretically. The results show that the conductivity and EMI shielding properties of BF/PANI composites can be tailored by adjusting the component, microstructure, and electromagnetic parameter, which can be easily tuned by modulating the weight ratio of aniline monomer and BF. More significantly, the BF/PANI heterostructures exhibit remarkable enhanced EMI shielding capabilities compared with the pristine PANI. The BF/PANI heterostructure prepared with an aniline volume of 7 mL shows an electrical conductivity of 6.07 S·cm–1 and the best EMI shielding capabilities of 35.73 dB. The excellent microwave attenuation capacity can be attributed to the cooperation of interface polarization, conductivity, skin depth effect, and the novel heterostructure. Considering their fascinating performance, these BF/PANI composites are proving to be the promising candidates as highly efficient EMI shielding materials.

Ultra-fast heat dissipating aerogels derived from polyaniline anchored cellulose nanofibers as sustainable microwave absorbers

“…Conducting polymer nanocomposites containing carbonaceous nanofillers such as CNTs and graphene have received burgeoning research interests to replace conventional metallic shields due to their high end mechanical and electrical properties (Al-Saleh & Sundararaj, 2009;Chen et al, 2016;Shen, Zhai, & Zheng, 2014;Yan et al, 2015;Yang, Gupta, Dudley, & Lawrence, 2005;Zeng et al, 2016). Moreover, intrinsically conducting polymers such as Polypyrrole (PPy) (Guo et al, 2017;Kaur, Ishpal, & Dhawan, 2012), Polythiophenes (PTs) (Dar et al, 2017;Kulkarni et al, 2019) Poly (3,4-ethylenedioxythiophene) (PEDOT) (Dalal et al, 2019;Luo, Zhang, Mei, Chang, & Yan, 2016) and Polyaniline (PANI) (Joseph, Varghese, & Sebastian, 2015;Zhang et al, 2019) has also been of great interest for EMI shielding applications. Very recently, 2D transition metal carbides and nitrides (MXene) have gathered much attention for developing next generation high performance EMI shielding materials (Cao et al, 2018;Sun et al, 2017;Wang et al, 2019;Weng et al, 2018;Zhao et al, 2018).…”

2D nanosheets and composites for EMI shielding analysis

“…EMI shielding effectiveness (SE) measurements are performed using vector network analyser system (Fig. 3 ) in 1–8 GHz frequency range 20 . Experimentally, EMI SE is measured in decibels (dB) as the logarithmic ratio of incoming power (P I ) to transmitted power (P T ).…”

Conductive Skeleton–Heterostructure Composites Based on Chrome Shavings for Enhanced Electromagnetic Interference Shielding

“…A prefabricated conductive skeleton has been proven to outperform a traditional filler-mixed loading − in terms of enlarging conductive loss, particularly in conductive polymer EMI shielding materials. ,,,− Meanwhile, metals, − carbon materials , and intrinsically conductive polymers ,− can be coated on the fiber to also achieve the efficacy of a conductive skeleton. To increase the polarized loss, building heterogeneous interfaces is a novel strategy, and the heterostructure can accumulate sufficient electric charge to weaken the incident electromagnetic waves (EMWs). ,− Typical structures are multilayer materials and core–shell nanostructures. , Moreover, reasonable space structure design of the reflection layer and absorption layer also have great synergistic effects on EMI shielding performance ,,,− in layered materials. In the structure of the “reflection layer (bottom)/absorption layer (top)”, the propagation paths of EMWs will be extended by the high reflection layer at the bottom and the EMWs will be fully consumed by the two layers …”

“…15,36−38 Typical structures are multilayer materials 15 and core−shell nanostructures. 36,38 Moreover, reasonable space structure design of the reflection layer and absorption layer also have great synergistic effects on EMI shielding performance 15,17,18,39−43 in layered materials. In the structure of the "reflection layer (bottom)/absorption layer (top)", the propagation paths of EMWs will be extended by the high reflection layer at the bottom and the EMWs will be fully consumed by the two layers.…”