Toward Carbon Monoxide Methanation at Mild Conditions on Dual-Site Catalysts

The catalytic carbon monoxide (CO)
methanation is an
ideal model
reaction for the fundamental understanding of catalysis on the gas–solid
interface and is crucial for various industrial processes. However,
the harsh operating conditions make the reaction unsustainable, and
the limitations set by the scaling relations between the dissociation
energy barrier and dissociative binding energy of CO further increase
the difficulty in designing high-performance methanation catalysts
operating under milder conditions. Herein, we proposed a theoretical
strategy to circumvent the limitations elegantly and achieve both
facile CO dissociation and C/O hydrogenation on the catalyst containing
a confined dual site. The DFT-based microkinetic modeling (MKM) reveals
that the designed Co-Cr2/G dual-site catalyst could provide
4–6 orders of magnitude higher turnover frequency for CH4 production than the cobalt step sites. We believe that the
proposed strategy in the current work will provide essential guidance
for designing state-of-the-art methanation catalysts under mild conditions.