Conversion of methane to C₂ liquid oxygenates by Ru atom arrays.

Abstract

The efficient conversion of methane to valuable C₂ liquid oxygenates still remains silent. Here we show a new catalytic system of C-C coupling towards the C₂ liquid oxygenates with high selectivity and productivity by the selective anchoring zero-valent ruthenium atoms from individual ones to two and three atoms in the electron-rich 18-carbon cavity of graphdiyne. Theoretical calculations demonstrate that Ru₃-GDY supplies neighboring robust active sites to promote efficient C-C coupling to C₂ liquid oxygenates, due to the p-d coupling resonance that guarantees the distributed charge among Ru₃ sites resulting in active region to accelerate the methane oxidation. Our results show Ru atoms in GDY enable the highly efficient and selective activation of CH₄ to the key ·CH₃ and ·CH₂OH intermediates, which allows the selective C-C coupling to gain C₂ liquid oxygenates and shows the high selectivity (67%) and yields (7.25 mmol g_cat^-1 h^-1) towards C₂ liquid oxygenates.