Hydrothermal Synthesis of Reduced Graphene Oxide Using Urea as Reduction Agent: Excellent X-band Electromagnetic Absorption Properties

5th International Conference on Advanced Materials Sciences and Technology

Agusu, L.^1 ; Ahmad, L.O.^2 ; Alimin^2 ; Nurdin, M.^3 ; Herdianto^3 ; Mitsudo, S.^3 ; Kikuchi, H.^3

Department of Physics, Faculty of Mathematics and Sciences, Universitas Halu Oleo, Kampus Bumi Tridharma Anduonohu, Kendari

93232, Indonesia^1

Department of Chemistry, Faculty of Mathematics and Sciences, Universitas Halu Oleo, Kampus Bumi Tridharma Anduonohu, Kendari

93232, Indonesia^2

Research Center for Development of Far-Infrared Region, University of Fukui, 3-9-1 Bunkyo, Fukui

910-8507, Japan^3

关键词: Hydrothermal process;    Layered Structures;    Localized spin;    Microwave energies;    Reduced graphene oxides;    Reduction agents;    Reflection loss;    Strong absorptions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/367/1/012002/pdf
DOI  :  10.1088/1757-899X/367/1/012002

来源: IOP

【 摘 要 】

We report a strong absorption of microwave energy at X-band (8 GHz to 12 GHz) by N-doped graphene. Attachment of nitrogen on the layered structure of GO improves the reflection loss of GO slab (2.0 mm, thickness) from -10 dB to -25.0 dB with a sharp bandwidth ∼0.3 GHz. As for the broader bandwidth of about 1.4 GHz, reflection loss is -10.5 dB. This significant absorption may take place by improvement of magnetic property of NG through high magnetic coupling of localized spins induced by a defect on the surface of graphene. N atoms play as the electron trapper, easily influenced by self-magnetic moments and incoming electromagnetic fields to produce electric and/or magnetic losses. Here, urea acts as the reducing agent and N atoms donor for graphene oxide in hydrothermal process at a temperature of 190 °C.