Novel g-C3N4/CeO2 nanocomposites were synthesized through a simple mixing-calcination method. The structure, morphology and composition of g-C3N4/CeO2 nanocomposites were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), as well as X-ray photoelectron spectroscopy (XPS). The results indicated that CeO2 nanoparticles with a diameter of 50-100 nm were uniformly loaded on the surface of g-C3N4. Furthermore, the catalytic effect of our prepared novel g-C3N4/CeO2 nanocomposites on the thermal decomposition of ammonium perchlorate (AP) was investigated by utilizing thermogravimetric and differential thermal analyses (TG-DTA). Compared with pure g-C3N4 and CeO2, the g-C3N4/CeO2 nanocomposites were proved to catalyze the thermal decomposition of AP more effectively. Upon addition of g-C3N4/CeO2 nanocomposites, the high weight-loss decomposition temperature of AP was decreased by up to 74.6 degrees C, which is quite more than that upon the addition of pure g-C3N4 and CeO2. The proposed mechanism demonstrated that this situation was presumably attributed to a synergistic effect between g-C3N4 and CeO2. (C) 2015 Elsevier B.V. All rights reserved.