CO2 hydrogenation over Fe-Co bimetallic catalysts with tunable selectivity through a graphene fencing approach
Jiaming Liang, Jiangtao Liu, Lisheng Guo, Wenhang Wang, Chengwei Wang, Weizhe Gao, Xiaoyu Guo, Yingluo He, Guohui Yang, Shuhei Yasuda, Bing Liang, Noritatsu Tsubaki
Abstract
Abstract Tuning CO 2 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 2 /H 2 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 2 direct hydrogenation to liquefied petroleum gas via a Fischer-Tropsch pathway with the highest space-time yields compared to other reported composite catalysts.