Investigation onto the performance and mechanism of visible light photodegradation of methyl orange catalyzed by M/CeO2 (M=Pt, Ag, Au)

•M/CeO2 (M=Pt, Ag, Au) was prepared and used for photodegradation of MO.•Structure, morphology and optical properties of M/CeO2 were investigated.•The various factors on the photocatalytic degradation efficiency of MO were studied.•The active species of photodegradation are hydroxyl and superoxide radicals.•Photocatalytic mechanism based on work function and electron transfer was discussed.