A novel donor–acceptor heterojunction from single-walled carbon nanotubes functionalized by erbium bisphthalocyanine

Organic functionalization of single-walled carbon nanotubes (SWNTs) was realized by chemical reaction of octaamino substituted erbium bisphthalocyanine (OAErPc2) and SWNTs with carboxyl groups, and SWNTs covalently bonded by OAErPc2 via amide bond as a donor–acceptor (D–A) heterojunction were obtained. FTIR and thermal analysis indicated that the amide bond formed as a bridge between OAErPc2 (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 OAErPc2 to SWNTs was observed from the Raman shift, which was expected to facilitate the photoinduced charge transfer and the development of photodetectors.