The electronic interaction of encapsulating graphene layers with FeCo alloy promotes efficient CO2 Hydrogenation to light olefins

Abstract

ABSTRACT

CO₂ hydrogenation to value-added light olefins (C_2–4⁼) is crucial for the utilization and cycling of global carbon resource. Moderate CO₂ activation and carbon chain growth ability are key factors for iron-based catalysts for efficient CO₂ conversion to target C_2–4⁼ products. The electronic interaction and confinement effect of electron-deficient graphene inner surface on the active phase are effective to improve surface chemical properties and enhance the catalytic performance. Here, we report a core-shell FeCo alloy catalyst with graphene layers confinement prepared by a simple sol-gel method. The electron transfer from Fe species to curved graphene inner surface modifies the surface electronic structure of the active phase χ-(Fe_xCo_1–x)₅C₂ and improves CO₂ adsorption capacity, enhancing the efficient conversion of CO₂ and moderate C-C coupling. Therefore, the catalyst FeCoK@C exhibits C_2–4⁼ selectivity of 33.0% while maintaining high CO₂ conversion of 52.0%. The high stability without obvious deactivation for over 100 h and unprecedented C_2–4⁼ space time yield (STY) up to 52.9 mmol_CO2·g^–1·h^–1 demonstrate its potential for practical application. This work provides an efficient strategy for the development of high-performance CO₂ hydrogenation catalysts.