Ceria doped TiO2 as photocatalyst for water treatment under visible light

Abstract

Abstract The photocatalytic activity of bare titania and ceria supported mesoporous titania (CeO2/TiO2) catalysts were assessed for the degradation of caffeine by visible light irradiation in absence of the oxidants. Different wt% metal loaded (bare, 0.1, 0.5 and 1.0) materials were synthesised by a sol-gel method using anionic surfactants. Various instrumentation techniques were used to characterise the prepared photo-catalysts such as P-XRD, BET, TEM, SEM-EDX, FT-IR, Raman, UV-DRS and photoluminescence spectroscopy. 0.5% CeO2 doped titania exhibited excellent efficiency in photo degradation of caffeine in aqueous solution relative to all the other prepared heterogeneous catalysts. All the materials showed good efficiency and were recyclable without loss of catalytic activity up to three times. Analysis of degradation products was carried by Liquid chromatograph-mass spectrometry. Two reaction products 6-amino-1,3-dimethyl-2,4-dioxo-1,2,3,4-tetradropymidin-5-ly)-methylcarbamic acid (ATCA) and N-methyl-N-(methylcarbomoyl)-2-oxoacetamide (MMO) were positively identified.