The Synergistic Effect in CoMoO _x Enhanced CO ₂ Hydrogenation to CO

ABSTRACT Co‐based catalysts were reported to be active in CO 2 hydrogenation to CH 4 . Herein, we reported the selectivity of CoO x catalysts could be modulated from CH 4 to CO after modifying by MoO x , which was almost inactive in CO 2 hydrogenation. The strong interaction between CoO x and MoO x species in CoMoO x resulted in decent catalytic performance in CO 2 hydrogenation to CO, with the highest CO 2 conversion of ∼38% and a high CO selectivity of ∼99%. The strong interaction between CoO x and MoO x induced the formation of rich oxygen vacancy, which promoted adsorption of CO 2 on oxygen vacancies neighboring MoO x , while H 2 was activated in CoO x sites. Compared with CoO x and MoO x , bicarbonate species were detected during the in situ CO 2 hydrogenation to CO. This work illustrated the critical role of synergistic effect in tuning the selectivity in CO 2 hydrogenation.