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In this work, a Pt catalyst supported on an equimolar Al 2 O 3 –CeO 2 binary oxide (Pt–Al–Ce) was prepared and applied in photo-thermo-chemical dry reforming of methane (DRM) driven by concentrated solar irradiation. It was found that the Pt–Al–Ce catalyst showed good stability in DRM reactions and significant enhancements in H 2 and CO production rates compared with Pt/CeO 2 (Pt–Ce) and Pt/Al 2 O 3 (Pt–Al) catalysts. At a reaction temperature of 700 °C under 30-sun equivalent solar irradiation, the Pt–Al–Ce catalyst exhibits a stable DRM catalytic performance at a H 2 production rate of 657 mmol g −1 h −1 and a CO production rate of 666 mmol g −1 h −1 , with the H 2 /CO ratio almost equal to unity. These production rates and the H 2 /CO ratio were significantly higher than those obtained in the dark at the same temperature. The light irradiation was found to induce photocatalytic activities on Pt–Al–Ce and reduce the reaction activation energy. In situ diffuse reflectance infrared Fourier transform spectroscopy ( in situ DRIFTS) was applied to identify the active intermediates in the photo-thermo-chemical DRM process, which were bidentate/monodentate carbonate, absorbed CO on Pt, and formate. The benefits of the binary Al 2 O 3 –CeO 2 substrate could be ascribed to Al 2 O 3 promoting methane dissociation while CeO 2 stabilized and eliminated possible coke formation, leading to high catalytic DRM activity and stability. 

In this study, Mg²⁺‐doped mesoporous TiO₂photocatalysts derived from Mg²⁺adsorption (MA) process on MIL‐125, a metal‐organic framework material, were prepared and employed for photocatalytic reduction of CO₂to produce CO. The Mg²⁺doping concentration was controlled by varying the Mg²⁺concentration in the Mg²⁺adsorption process. It was demonstrated that the Mg²⁺doping promoted the generation of surface Ti³⁺and significantly increased transient photocurrent density. Over a 4 h UV/Vis irradiation period, the best performing photocatalyst, 1MA, delivered a CO production rate ∼20 times higher than that of P25, a commercially available TiO₂nanopowder. It is believed that the Mg²⁺adsorption process introduced more favorable properties to the TiO₂photocatalysts, such as higher surface area and porosity for more reactive sites, and concentrated surface Ti³⁺centers for improved charge transfer.