Electrochemically modified single-walled carbon nanotubes

We report on the properties of electrochemically modified SWCNTs bearing a functional organic layer and a low density of noble metal nanoparticles, respectively. First, a novel approach to nanoscale pH sensors is demonstrated which involves the gentle modification of individual metallic tubes via covalent attachment of amino-substituted phenyl groups. Furthermore, gold particles with sizes of a few tens of nanometres deposited onto individual SWCNTs were found to locally enhance the Raman signals of the underlying nanotube. The enhancement imparted by individual gold particles was estimated to be two orders of magnitude. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.