Molybdenum Sulfides and Selenides as Possible Electrocatalysts for CO2 Reduction

Linear scaling relations between reaction intermediates pose a fundamental limitation to the CO2 reduction activity of transition- metal catalysts. To design improved catalysts, we propose to break these scaling relations by binding key reaction intermediates to different sites. Using density functional theory, we demonstrate this principle in the active edge sites in MoS2, MoSe2, and Ni-doped MoS2. These edges show the unique property of selectively binding COOH and CHO to bridging S or Se atoms and CO to the metal atom. DFT calculations suggest a significant improvement in CO2 reduction activity over the transition metals. Our results point to the broader application of the active edge sites of transition-metal dichalcogenides in complex electrochemical processes.