TY - CONF
T1 - Graphene foam/conductive polymer composites for lightweight electromagnetic interference shielding
AU - Wu, Ying
AU - Wang, Zhenyu
AU - Liu, Xu
AU - Shen, Xi
AU - Zheng, Qingbin
AU - Kim, Jang Kyo
N1 - Funding Information:
This project was financially supported by the Research Grants Council of Hong Kong SAR (GRF Projects: 16203415 and 16229216). Technical assistance from the Advanced Engineering Material Facility and the Materials Characterization and Preparation Facilities at HKUST, and Applied Electromagnetics Laboratory at City University of Hong Kong is also appreciated.
Publisher Copyright:
© 2017 International Committee on Composite Materials. All rights reserved.
PY - 2017
Y1 - 2017
N2 - This paper presents our recent work [1]on developing a novel and facile strategy for the fabrication of highly conductive and lightweight graphene foam (GF)/poly(3, 4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) composites for effective electromagnetic interference (EMI) shielding. The surfactant, 4-dodecylbenzenesulfonic acid, is applied for noncovalent functionalization of cellular-structured, freestanding GFs to enhance the wettability and the interfacial interactions between GFs and PEDOT: PSS and thus help coat PEDOT: PSS on GFs. A uniform and highly porous structure is developed, showing a high porosity of 98.8% and a low density of 18.2× 10-3 g/cm3. A much enhanced electrical conductivity from 11.8 to 43.2 S/cm is achieved and discussion is made of interfacial interactions and physical/morphological changes on both the microscopic and nanoscopic scales. The highly conductive PEDOT: PSS coating bridges resistive grain boundaries and connects open areas of the cellular structure of GFs. Negative permittivities and permeabilities are observed for the composites, an indication of charge delocalization at the interfaces of PEDOT: PSS and GFs on a microscopic scale. Thanks to the lightweight porous structure, excellent electrical conductivities and effective charge delocalization, the GF/PEDOT: PSS composites deliver exceptional EMI shielding performances with a shielding effectiveness (SE) of 91.9 dB and specific SEs of 3124 dB·cm3/g and 20800 dBcm2/g normalized by volumetric and area densities, respectively. These excellent EMI shielding performances are among the best of reported values for different composites. The remarkable EMI shielding properties and proposed mechanisms in this work can shed new insights into how one can improve EMI shielding performance.
AB - This paper presents our recent work [1]on developing a novel and facile strategy for the fabrication of highly conductive and lightweight graphene foam (GF)/poly(3, 4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) composites for effective electromagnetic interference (EMI) shielding. The surfactant, 4-dodecylbenzenesulfonic acid, is applied for noncovalent functionalization of cellular-structured, freestanding GFs to enhance the wettability and the interfacial interactions between GFs and PEDOT: PSS and thus help coat PEDOT: PSS on GFs. A uniform and highly porous structure is developed, showing a high porosity of 98.8% and a low density of 18.2× 10-3 g/cm3. A much enhanced electrical conductivity from 11.8 to 43.2 S/cm is achieved and discussion is made of interfacial interactions and physical/morphological changes on both the microscopic and nanoscopic scales. The highly conductive PEDOT: PSS coating bridges resistive grain boundaries and connects open areas of the cellular structure of GFs. Negative permittivities and permeabilities are observed for the composites, an indication of charge delocalization at the interfaces of PEDOT: PSS and GFs on a microscopic scale. Thanks to the lightweight porous structure, excellent electrical conductivities and effective charge delocalization, the GF/PEDOT: PSS composites deliver exceptional EMI shielding performances with a shielding effectiveness (SE) of 91.9 dB and specific SEs of 3124 dB·cm3/g and 20800 dBcm2/g normalized by volumetric and area densities, respectively. These excellent EMI shielding performances are among the best of reported values for different composites. The remarkable EMI shielding properties and proposed mechanisms in this work can shed new insights into how one can improve EMI shielding performance.
KW - Electrical conductivity
KW - EMI shielding
KW - Graphene foam composites
KW - Ultralightweight
UR - http://www.scopus.com/inward/record.url?scp=85053156103&partnerID=8YFLogxK
M3 - Paper
AN - SCOPUS:85053156103
T2 - 21st International Conference on Composite Materials, ICCM 2017
Y2 - 20 August 2017 through 25 August 2017
ER -