Photoreduction of CO2 on ZIF-8/TiO2 nanocomposites in a gaseous photoreactor under pressure swing

- A new type of ZIF-8/TiO2 core-shell nanocomposite is designed to facilitate not only CO2 adsorption but also its subsequent photoreduction.
- Sequential fluctuation of reactor pressure plays an important role in promoting product desorption and increasing photocatalyst activity.
- This study highlights the significance of engineering variables including mass transfer and reactor design in photocatalytic reactions.

A new type of zeolitic imidazolate framework ZIF-8/TiO2 nanocomposites was developed for photocatalytic reduction of CO2 to CH4 and CO in a newly designed photoreactor under intentionally controlled pressure swing. The ZIF-8/TiO2 core-shell structure plays an important role in the adsorption of CO2 by ZIF-8 and subsequent in-situ photocatalytic reduction on TiO2. The introduction of pressure change in the reaction system facilitates the adsorption-desorption process of CO2 and reaction products, which consequently led to improved photoreduction performance. This approach highlights the importance of mass transfer and reactor design for improved photoreduction.

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