Enhanced Fischer–Tropsch synthesis performance on MOFs-derived Fe-based catalysts constrained by SiO2

Fischer–Tropsch synthesis (FTS) is an essential technology to produce clean fuel, and catalyst will affect syngas conversion efficiency and product distribution. For traditional oxides-supported catalysts, the mutual constraint between active metal loading and dispersion at high metal loading is hard to overcome, which will hinder the synthesis of high-performance FTS catalysts. Herein, we report an efficient method for synthesizing iron-based catalysts with not only high loading but also high dispersion. By using metal–organic frameworks Fe-MIL-88B as the precursor, we synthesized a series of Fe@C@SiO 2 catalysts by tuning the amount of tetraethyl orthosilicate (TEOS) through a one-step method; TEOS was in situ introduced and followed by high-temperature carbonization. The prepared catalyst possesses a Fe@C core–shell structure with carbon layer encapsulation. Meanwhile, the SiO 2 in the catalyst can effectively confine iron particles and avoid the agglomeration of iron species during high-temperature carbonization. Among these catalysts, the Fe@C@SiO 2 -0.005 showed the greatest FTS performance because high iron dispersion was achieved at high iron loading. Further increase SiO 2 content enhanced the confinement effect of SiO 2 but generated inert Fe 2 SiO 4 species, which decreased the adsorption and activation of reactants and FTS activity.