Highly Active and Stable Catalysts Derived from Bimetal-ZIFs for Selective CO2 Hydrogenation to Valuable Hydrocarbons

Transformation of abundant and economical feedstock CO2 and renewable H2 into valuable hydrocarbons is considered a prospective route for the storage of renewable energy. However, it is also a challenge to prepare highly stable and active catalysts. Herein, active and stable catalysts were designed by pyrolysis of the Fe-modified bimetal-ZIFs with varied ratios of Zn/Co, in order to introduce Zn in situ as a structure promoter and Co for an increase of the CO2 conversion. CO2 conversion increased by improving the Co content, while CH4 selectivity also increased obviously. The superior selectivity of value-added hydrocarbons and the ratio of olefins and paraffins (O/P) were obtained without addition of alkali metals. The O/P is 1.76 over FeZnCo-NC-59. The N-doped porous carbon catalysts delivered a good stability in a 1000 h test under harsh reaction conditions. The stable catalysts provide a promising prospect for further application in CO2 hydrogenation.