A method is provided for modifying a surface of a solid conducting material, which includes applying a potential difference between this surface and a surface of another conducting solid material positioned facing it, and wherein, simultaneously, the surface (S) is put into contact with a liquid medium comprising in solution triarylamines (I): while subjecting these triarylamines (I) to electromagnetic radiation, at least partly converting them at into triarylammonium radicals. Also provided is a conducting device which includes two conducting metal materials, the surfaces of which, (S) and (S′) respectively, are electrically interconnected through an organic material comprising conducting fibrillar organic supramolecular species comprising an association of triarylamines of formula (I).