An electromagnetic radiation attenuating material or coating consistent with certain embodiments of the present invention uses a binding matrix with an operative quantity of electromagnetic radiation attenuating nano-particles suspended in the binding matrix, wherein, the electromagnetic radiation attenuating nano-particles comprise onion-like-carbon (OLC) particles. In other embodiments, freestanding structures, aerosols and powders or suspensions contained within an enclosure provide EM or Radar absorption, particularly in the range of about 500 MHz to about 30 THz. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.