CO<sub>2</sub> hydrogenation over Fe-Co bimetallic catalysts with tunable selectivity through a graphene fencing approach.

Liang, Jiaming; Liu, Jiangtao; Guo, Lisheng; Wang, Wenhang; Wang, Chengwei; Gao, Weizhe; Guo, Xiaoyu; He, Yingluo et al. · Nat Commun · 2024

basic_science · Level V

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Abstract

Tuning CO<sub>2</sub> hydrogenation product distribution to obtain high-selectivity target products is of great significance. However, due to the imprecise regulation of chain propagation and hydrogenation reactions, the oriented synthesis of a single product is challenging. Herein, we report an approach to controlling multiple sites with graphene fence engineering that enables direct conversion of CO<sub>2</sub>/H<sub>2</sub> mixtures into different types of hydrocarbons. Fe-Co active sites on the graphene fence surface present 50.1% light olefin selectivity, while the spatial Fe-Co nanoparticles separated by graphene fences achieve liquefied petroleum gas of 43.6%. With the assistance of graphene fences, iron carbides and metallic cobalt can efficiently regulate C-C coupling and olefin secondary hydrogenation reactions to achieve product-selective switching between light olefins and liquefied petroleum gas. Furthermore, it also creates a precedent for CO<sub>2</sub> direct hydrogenation to liquefied petroleum gas via a Fischer-Tropsch pathway with the highest space-time yields compared to other reported composite catalysts.