Photo-thermo-catalytic H2 production over flame made CeO2-Pt/TiO2

• CeO 2 -Pt/TiO 2 photocatalyst was synthetized in single step by flame spray pyrolysis. • Temperature strongly influences the photocatalytic performances. • Low ceria loading (5 wt%) leads to higher water conversion and selectivity to CO 2. • High ceria loading (50 wt%) promotes rutile formation and shifts activity to higher T. • CeO 2 boosts H 2 production and selectivity to CO 2 due to water gas shift reaction. The photo-thermo-catalytic production of H 2 by methanol steam reforming (MSR) was studied in an innovative home-made bench scale setup which allows to evaluate the synergistic effect of heat and UV–vis light irradiation. The variation of the concentrations of all reactants, intermediates, and products as a function of temperature were monitored in real-time by calibrated mass spectrometry. CeO 2 -Pt/TiO 2 composite photocatalysts were prepared in continuous and single step by flame spray pyrolysis (FSP) with different ceria loading (5 or 50 wt%). The catalytic performance of the FSP materials were compared with that of pure Pt/TiO 2 or CeO 2 alone or their mechanical mixture. It was found that temperature strongly affects the photocatalytic performance in terms of methanol and water conversion (X CH3OH and X H2O ), hydrogen production rate ( r H2 ), and selectivity towards the different products of methanol oxidation (formaldehyde, carbon monoxide and carbon dioxide). The addition of 5 wt% of ceria to 0.75 wt% Pt/TiO 2 led to an improved photo-thermo-catalytic performance at temperature above 150 °C. In contrast, a high ceria loading up to 50 wt% was found to be detrimental. The best catalytic performance was achieved over the catalyst obtained by mechanical mixing of 50 wt% of CeO 2 with Pt/TiO 2 leading to a significant increase of X CH3OH , X H2O , r H2 and selectivity to CO 2 with a maximum at 350 °C of ca. 100 %, 17 %, 431 mmol H2 h −1 g cat −1 and 18 %, respectively, due to the parallel Water Gas Shift (WGS) reaction promoted by CeO 2 .