International Journal of Nanoscience Vol. 7, Nos. 4 & 5 (2008) 263–268 c  World Scientific Publishing Company MODIFIED EXFOLIATED GRAPHITE AS A MATERIAL FOR SHIELDING AGAINST ELECTROMAGNETIC RADIATION LYUDMILA VOVCHENKO, LYUDMILA MATZUI, VIKTOR OLIYNYK, VILEN LAUNETZ and YURIY PRYLUTSKYY Kyiv National Taras Shevchenko University 64 Volodymyrska Street, Kyiv, 01033, Ukraine DAVID HUI Department of Mechanical Engineering University of New Orleans New Orleans, LA 70148, USA YURI M. STRZHEMECHNY ∗ Department of Physics and Astronomy Texas Christian University Fort Worth, TX 76129, USA Y.Strzhemechny@tcu.edu Revised 16 August 2008 We report on the structure and morphology of thermoexfoliated graphite (TEG) powders and TEG–metal (Co, Cu, Ni) powders. Electrodynamic parameters of the compacted TEG and TEG–metal specimens have been studied along the compacting axis (c axis) within the range of electromagnetic radiation frequencies between 25.5 and 37.5 GHz. Metal particles attached to the surface of the TEG particles yield enhanced radiation shielding within the entire frequency range. Moreover, it is observed that the absorption coefficient increases with the increase in conductivity of the metal particles and is enhanced due to a high concentration of TEG–metal boundaries, which promote multiple reflections. Keywords : Nanostructures; electrical properties; physical properties; porosity; electron microscopy; compression molding. 1. Introduction The rapid development of telecommunications tech- nology encountered an impediment related to the difficulties with the delivery of information at the final stage (the so-called “last mile problem”). This is linked to a more generic problem of electromagnetic compatibility of radioelectronic devices. Designing compact transmitting antenna systems yields an effective solution to the problem. Currently such systems operate primarily in the ∗ Corresponding author. 263 Int. J. Nanosci. 2008.07:263-268. Downloaded from www.worldscientific.com by 91.202.128.0 on 03/28/13. For personal use only.