Abstract
Direct catalytic hydrogenation of CO2 is a highly promising route for olefin synthesis. However, achieving high olefin selectivity is predicated on the development of a selective catalyst with acceptable yield and stability. Herein, we report a Sr and Na co-decorated Fe catalyst that showed stable performance in the synthesis of high-valued olefins (ethene, propene and linear α-olefins) with space-time yield up to 290 mg g_(cat)~(-1)h~(-1) without significant deactivation for over 500 h on-stream. The excellent catalytic performance is attributed to the cooperative effect of Sr and Na on the distinct sites (Fe5C2, Fe3C, Fe3O4) in catalyst. In particular, SrCO3 promoted the dispersion of binding Fe sites that facilitated the formation and stabilization of FeC_x phase. Simultaneously, Sr contributed to the electron interaction between Na and Fe species. The dual effect of Sr as both structural and electronic promoters coordinatively improved C-O dissociative adsorption and subsequent C-C coupling, thus facilitated CO2 hydrogenation.
NSTL