Carbon-graphene-epoxy sandwich dielectric for improved dielectric response to humidity

Anupama Shivamurthy; Raviprasad Kogravalli Jagannat; Gurusiddappa R. Prashanth; Suresha B; N. Rajini; Farid F. Muhammed; Hamad A. Al-Lohedan; Rakshith Boranna; Kumar Krishnan

Journal of Materials Research and Technology (Nov 2023)

Carbon-graphene-epoxy sandwich dielectric for improved dielectric response to humidity

Anupama Shivamurthy,
Raviprasad Kogravalli Jagannat,
Gurusiddappa R. Prashanth,
Suresha B,
N. Rajini,
Farid F. Muhammed,
Hamad A. Al-Lohedan,
Rakshith Boranna,
Kumar Krishnan

Affiliations

Anupama Shivamurthy: Department of Electronics and Communication Engineering, National Institute of Technology Goa, Goa 403401, India
Raviprasad Kogravalli Jagannat: Department of Applied Science, National Institute of Technology Goa, Goa 403401, India
Gurusiddappa R. Prashanth: Department of Electronics and Communication Engineering, National Institute of Technology Goa, Goa 403401, India; Corresponding author.
Suresha B: Department of Mechanical Engineering, The National Institute of Engineering, Mysuru 570 008, India; Corresponding author.
N. Rajini: Department of Mechanical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil 626 126, Tamilnadu, India; INTI International University, Persiaran Perdana BBN, Nilai, Negeri Sembilan 71800, Malaysia; Corresponding author.
Farid F. Muhammed: Department of Mechanical Engineering, Southern University, Baton Rouge, LA 70813, USA
Hamad A. Al-Lohedan: Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia
Rakshith Boranna: Department of Electronics and Communication Engineering, JSS Science and Technology University, Mysuru 570006, Karnataka, India
Kumar Krishnan: Department of Electronics and Communication Engineering, National Institute of Technology Goa, Goa 403401, India; Department of Applied Science, National Institute of Technology Goa, Goa 403401, India; Department of Mechanical Engineering, The National Institute of Engineering, Mysuru 570 008, India; Department of Mechanical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil 626 126, Tamilnadu, India; INTI International University, Persiaran Perdana BBN, Nilai, Negeri Sembilan 71800, Malaysia; Department of Mechanical Engineering, Southern University, Baton Rouge, LA 70813, USA; Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia; Department of Electronics and Communication Engineering, JSS Science and Technology University, Mysuru 570006, Karnataka, India; Faculty of Health and Life Sciences, INTI International University, Persiaran Perdana BBN, Nilai, Negeri Sembilan 71800, Malaysia

Journal volume & issue: Vol. 27
pp. 1711 – 1723

Abstract

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A sandwich structure of carbon-epoxy laminate with graphene nanoplatelets is used for increasing the AC conductivity, dielectric constant and sensitivity towards moisture. The Quasi Fickian distribution of moisture absorption of epoxy is retained with the inclusion of carbon fibers and graphene nanoplatelets of 1 weight percent. The effect of relative humidity (RH) over a range of 30–90% on AC conductivity and capacitance has been investigated. Use of carbon fibers with graphene nanoplatelets significantly enhances the electrical conductivity and dielectric constant as compared to carbon-epoxy laminate without graphene nanoplatelets. The two parameters reveal linear dependence on humidity in the low frequency range of 100–1000 Hz. The AC conductivity increases at the rate of 2 nSm−1/% RH in laminate with carbon fiber and it increases to 50 nSm−1/%RH with the incorporation of graphene nanoplatelets. The increase in AC conductivity from 100 Hz to 1000 Hz is in the range of 0.1 to 0.2 μS/m with carbon fibers and it increases from 1 to 4 μS/m with the inclusion of graphenenanoplatelets. Increase is AC conductivity from 1 kHz to 10 MHz is by five orders of magnitude, with a steep increase around 5 MHz in both laminates. The incorporation of graphenenanoplatelets helps to increase the dielectric constant by 2.4–2.8 times as compared to epoxy with carbon fiber. The swelling in the laminates estimated after 96 h of exposure to 90% RH is observed to be less than 0.05%. The use of graphenenanoplatelets improves moisture sensitivity of the carbon-epoxy laminate.

Published in Journal of Materials Research and Technology

ISSN: 2238-7854 (Print); 2214-0697 (Online)
Publisher: Elsevier
Country of publisher: Netherlands
LCC subjects: Technology: Mining engineering. Metallurgy
Website: https://www.journals.elsevier.com/journal-of-materials-research-and-technology/

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