AgI nanoparticles (NPs) have been decorated on the TiO2 nanobelts (NBs) immobilized on a metal Ti substrate by a simple impregnating-precipitation method. The as-achieved Agl/TiO2 monolithic catalyst exhibits a high and stable visible photocatalytic activity toward acid orange II (AO-II) degradation, which is attributed to the suitable energy band match of AgI NPs and TiO2 NBs, leading to the efficient transfer of photo-generated electrons. In addition, it was found that O-center dot(2)- radicals and h(+) are the main reactive species for the degradation of AO-II under visible light irradiation. A reasonable photocatalytic mechanism of Agl/TiO2 photocatalyst toward AO-II degradation was discussed. This monolithic catalyst provides an advantage over the drawback encountered with powder suspension. (C) 2014 Elsevier B.V. All rights reserved.