Highly efficient, selective, and stable photocatalytic methane coupling to ethane enabled by lattice oxygen looping.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38941471.
- Also identified by DOI 10.1126/sciadv.ado4390 and PMC identifier 11637002.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Light-driven oxidative coupling of methane (OCM) for multi-carbon (C<sub>2+</sub>) product evolution is a promising approach toward the sustainable production of value-added chemicals, yet remains challenging due to its low intrinsic activity. Here, we demonstrate the integration of bismuth oxide (BiO<sub>x</sub>) and gold (Au) on titanium dioxide (TiO<sub>2</sub>) substrate to achieve a high conversion rate, product selectivity, and catalytic durability toward photocatalytic OCM through rational catalytic site engineering. Mechanistic investigations reveal that the lattice oxygen in BiO<sub>x</sub> is effectively activated as the localized oxidant to promote methane dissociation, while Au governs the methyl transfer to avoid undesirable overoxidation and promote carbon─carbon coupling. The optimal Au/BiO<sub>x</sub>-TiO<sub>2</sub> hybrid delivers a conversion rate of 20.8 millimoles per gram per hour with C<sub>2+</sub> product selectivity high to 97% in the flow reactor. More specifically, the veritable participation of lattice oxygen during OCM is chemically looped by introduced dioxygen via the Mars-van Krevelen mechanism, endowing superior catalyst stability.