Highly efficient synthesis of higher oxygenates, especially higher alcohols, directly from syngas is promising, but it is also challenging because of the requirement of coordination between CO dissociative and non-dissociative sites. Monometallic iron catalysts have a competitive advantage because of better contact of dual sites to achievehigh alcoholselectivity. Here, aremarkable oxygenateselec-tivity of 69.7 wt was realized over a synergistic iron catalyst with a Ca promoter alongside an alcohol fraction of 86.4 in oxygenates. Multiple characterizations showed that 2 wt Ca loading enabled the Ca-Fe catalyst to have high surface iron carbides with the proper Fe2C/(Fe5C2+Fe3C) ratio, which facilitated synergy of CO dissociation and non-dissociation. In situ surface reaction characterizations confirmed that the 2 wt Ca-Fe catalyst had moderate activation ability to balance dissociative and non-dissociative activation of CO, which favored better cooperation of *CO and *CHx to form the *CHx-*CO species, further promoting higher-alcohol formation.
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