A novel bicomponent catalyst, VO2 supported on multi-walled carbon nanotubes (MWCNTs) with defects as promoter (VO2-defects/MWCNTs) was synthesized for the hydroxylation of benzene to phenol. In the bicomponent system, VO2 nanoparticles with 2-10 nm were prepared by the spontaneous redox between V5+ and defects of MWCNTs. Moreover, defects of MWCNTs were firstly used as promoters for preventing the oxidation of phenol and transferring electrons in the catalysis. Thus, compared with other vanadium catalysts, VO2-defects/MWCNTs show excellent catalytic performance for the hydroxylation of benzene to phenol, which indicates defects as promoter are quite promising for catalyzing the hydroxylation of benzene. (C) 2011 Elsevier B.V. All rights reserved.