• 文献标题:   Microwave-Assisted Synthesis of Boron and Nitrogen co-doped Reduced Graphene Oxide for the Protection of Electromagnetic Radiation in Ku-Band
  • 文献类型:   Article
  • 作  者:   UMRAO S, GUPTA TK, KUMAR S, SINGH VK, SULTANIA MK, JUNG JH, OH IK, SRIVASTAVA A
  • 作者关键词:   microwave, reduced graphene oxide, electrical conductivity, variable range hoppingg. emi shielding
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244 EI 1944-8252
  • 通讯作者地址:   Banaras Hindu Univ
  • 被引频次:   59
  • DOI:   10.1021/acsami.5b05890
  • 出版年:   2015

▎ 摘  要

The electromagnetic interference (EMI) shielding of reduced graphene oxide (MRG), B-doped MRG (BMRG), N-doped MRG (N-MRG), and B-N co-doped MRG (B-N-MRG) have been studied in the Ku-band frequency range (12.8-18 GHz). We have developed a green, fast, and cost-effective microwave assisted route for synthesis of doped MRG. B-N-MRG shows high electrical conductivity in comparison to MRG, B-MRG and N-MRG, which results better electromagnetic interference (EMI) shielding ability. The co-doping of B and N significantly enhances the electrical conductivity of MRG from 21.4 to 124.4 Sm-1 because N introduces electrons and B provides holes in the system and may form a nanojunction inside the material. Their temperature-dependent electrical conductivity follows 2D-variable range hopping (2D-VRH) and Efros-Shldovskii-VRH (ES-VRH) conduction model in a low temperature range (T < 50 K). The spatial configuration of MRG after doping of B and N enhances the space charge polarization, natural resonance, dielectric polarization, and trapping of EM waves by internal reflection leading to a high EMI shielding of -42 dB (-99.99% attenuation) compared to undoped MR.G (-28 dB) at a critical thickness of 1.2 mm. Results suggest that the B-N-MRG has great potential as a candidate for a new type of EMI shielding material useful in aircraft, defense industries, communication systems, and stealth technology.