Dynamic carbon overlayered CuCo alloy promotes syngas to higher alcohols

Syngas (CO/H₂), sourced from coal, biomass, and shale gas, plays a crucial role in producing a wide range of industrially essential hydrocarbons and oxygenates through Fischer-Tropsch synthesis and its variations. Despite extensive research dating back nearly a century, transforming syngas into higher alcohols remains challenging due to issues with low selectivity and catalyst instability. Generally, more than 50% of CO in typical syngas conversions yields unwanted hydrocarbons, mainly alkanes. Herein, we develop a catalyst integrating a Mo₂C-matrix-supported CuCo alloy with hydrophobic graphitic carbon overlayers, achieving 80% selectivity toward value-added alcohols and olefins, of which 59% are higher alcohols, while limiting alkanes to around 10%. The overlayers dynamically participate in the reaction through carbon consumption and replenishment, generating carbon-overlayer-derived CH_x species that form an asymmetrically polarised coupling pair with CO-derived intermediates, thereby lowering the barrier for CO insertion and diverting CO from deoxygenation pathways leading to alkane and coke formation. Consequently, the yield of value-added products reaches four times that of typical benchmarks at 80% CO conversion with long-term stability. This work represents a substantial advance in higher alcohol synthesis and sheds new light on the catalytic role of surface carbon in syngas conversion.