ClAg₁₄(CC^tBu)₁₂ Nanoclusters as Efficient and Selective Electrocatalysts Toward Industrially Relevant CO₂ Conversion

Atomically precise metal nanoclusters (NCs) have emerged as a promising frontier in the field of electrochemical CO2 reduction reactions (CO2RR) because of their distinctive catalytic properties. Although numerous metal NCs are developed for CO2RR, their use in practical applications has suffered from their low-yield synthesis and insufficient catalytic activity. In this study, the large-scale synthesis and electrocatalytic performance of ClAg14(C equivalent to(CBu)-Bu-t)(12)(+) NCs, which exhibit remarkable efficiency in catalyzing CO2-to-CO electroreduction with a CO selectivity of over 99% are reported. The underlying mechanisms behind this extraordinary CO2RR activity of ClAg14(C equivalent to(CBu)-Bu-t)(12)(+) NCs are investigated by a combination of electrokinetic and theoretical studies. These analyses reveal that different active sites, generated through electrochemical activation, have unique adsorption properties for the reaction intermediates, leading to enhanced CO2RR and suppressed hydrogen production. Furthermore, industrially relevant CO2-to-CO electroreduction using ClAg14(C equivalent to(CBu)-Bu-t)(12)(+) NCs in a zero-gap CO2 electrolyzer, achieving high energy efficiency of 51% and catalyst activity of over 1400 A g(-1) at a current density of 400 mA cm(-2) is demonstrated.