Organic functionalization of single-walled carbon nanotubes (SWNTs) was realized by chemical reaction of octaamino substituted erbium bisphthalocyanine (OAErPC(2)) and SWNTs with carboxyl groups, and SWNTs covalently bonded by OAErPc(2) via amide bond as a donor-acceptor (D-A) heterojunction were obtained. FTlR and thermal analysis indicated that the amide bond formed as a bridge between OAErPc(2) (as a donor) and SWNTs (as an acceptor). Strong intramolecular interaction in this D-A heterojunction was found from UV-vis absorption and charge transfer from the phthalocyanine rings of OAErPc(2) to SWNTs was observed from the Raman shift, which was expected to facilitate the photoinduced charge transfer and the development of photodetectors. (c) 2005 Elsevier B.V. All rights reserved.