(Figure Presented) A novel versatile approach for the functionalization of multilayer fullerenes (carbon nano-onlons) has been developed, which involves the facile introduction of a variety of simple functionalities onto their surface by treatment with In situ generated diazonium compounds. This approach Is complemented by use of “click” chemistry which was used for the covalent Introduction of more complex porphyrin molecules. © 2010 American Chemical Society.