Stabilized ordered-mesoporous Co₃O₄ structures using Al pillar for the superior CO hydrogenation activity to hydrocarbons

The metal oxide pillared ordered-mesoporous Co₃O₄ was investigated to design a stable and superior catalyst for CO hydrogenation into linear hydrocarbons through Fischer-Tropsch Synthesis (FTS) reaction. Enhanced structural stability was observed in ordered-mesoporous Co₃O₄ even under hydrogen-excess conditions after modification with a metal oxide pillar of Al₂O₃. The mesoporous Co₃O₄ was synthesized using a hard template of highly ordered three dimensional mesoporous KIT-6. A small number of metal oxide pillars such as Al₂O₃, Mn₂O₄, and SiO₂ with 5wt% were subsequently added to the ordered-mesoporous Co₃O₄ through the incipient wetness impregnation method. The Al₂O₃-modifed mesoporous Co₃O₄ catalyst demonstrated superior CO conversion with a stable activity in CO hydrogenation reaction. The enhanced catalytic stability seems to be attributable to the lower mobility of the Al₂O₃ pillar which formed stronger interactions with the mesoporous Co₃O₄ inner surfaces. The Al₂O₃ modification can effectively stabilize ordered-mesoporous structures of Co₃O₄ by acting as an ordered mesoporous channel reactor and enhancing the transport rate of hydrocarbons formed during FTS reaction.