US Patent 7905992 Submerged surface with conductive nanoparticles

An electrically conductive surface of a submerged object comprises a polymer matrix, such as a resin, with a plurality of electrically conductive nanoparticles suspended within the polymer. The nanoparticles are preferably smaller than 100 nanometers in their minimum dimension. In addition, large electrically conductive particles can be suspended in the polymer. The larger particles are typically greater than 300 nanometers in minimum dimension. The larger particles can comprise carbon powder or fibers. The electrically conductive nanoparticles, which can be nanotubes or ferrules, for example, and the larger particles, which can be carbon powder or fibers, are suspended homogeneously within the polymer matrix for best results and most uniform electrical conduction through the thickness of the composite layer.