Shielded bifunctional nanoreactor enabled tandem catalysis for plasma methane coupling.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40382342.
- Also identified by DOI 10.1038/s41467-025-59709-y and PMC identifier 12085660.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The direct conversion of methane into valuable unsaturated C<sub>2</sub> hydrocarbons (C<sub>2</sub>H<sub>2</sub> and C<sub>2</sub>H<sub>4</sub>) attracts growing attention. Non-thermal plasma offers a promising approach for this process under mild conditions. However, the competing formation of C<sub>2</sub>H<sub>6</sub> and excessive dehydrogenation limit the selectivity toward C<sub>2</sub>H<sub>2</sub> and C<sub>2</sub>H<sub>4</sub>. Herein, we develop a promising shielded bifunctional nanoreactor with a hollow structure and mesoporous channels (Na<sub>2</sub>WO<sub>4</sub>-Mn<sub>3</sub>O<sub>4</sub>/m-SiO<sub>2</sub>) that effectively limits CH<sub>4</sub> overactivation and promotes selective coupling to form C<sub>2</sub>H<sub>2</sub> and C<sub>2</sub>H<sub>4</sub> under plasma activation, achieving 39% CH<sub>4</sub> conversion with 42.3% C<sub>2</sub>H<sub>2</sub> and C<sub>2</sub>H<sub>4</sub> fraction. This nanoreactor features isolated Na<sub>2</sub>WO<sub>4</sub> embedded within the channels and Mn<sub>3</sub>O<sub>4</sub> confined in the cavity of the SiO<sub>2</sub> hollow nanospheres, enabling internal tandem catalysis at co-located active sites. Na<sub>2</sub>WO<sub>4</sub> induces the conversion of diffused CH<sub>4</sub> and CH<sub>3</sub> into reactive intermediates (<sup>*</sup>CH and <sup>*</sup>CH<sub>2</sub>), which subsequently couple on the Mn<sub>3</sub>O<sub>4</sub> surface to form C<sub>2</sub>H<sub>2</sub> and C<sub>2</sub>H<sub>4</sub>. Furthermore, the mesoporous channels inhibit the plasma discharge within the nanoreactor, preventing deep dehydrogenation of CH<sub>x</sub> species to solid carbon. This nanoreactor demonstrates a highly selective route for the nonoxidative conversion of methane to valuable C<sub>2</sub> hydrocarbons, offering a new paradigm for the rational design of catalysts for plasma-driven chemical processes.