Shielded bifunctional nanoreactor enabled tandem catalysis for plasma methane coupling.

The direct conversion of methane into valuable unsaturated C hydrocarbons (CH and CH) attracts growing attention. Non-thermal plasma offers a promising approach for this process under mild conditions. However, the competing formation of CH and excessive dehydrogenation limit the selectivity toward CH and CH. Herein, we develop a promising shielded bifunctional nanoreactor with a hollow structure and mesoporous channels (NaWO-MnO/m-SiO) that effectively limits CH overactivation and promotes selective coupling to form CH and CH under plasma activation, achieving 39% CH conversion with 42.3% CH and CH fraction. This nanoreactor features isolated NaWO embedded within the channels and MnO confined in the cavity of the SiO hollow nanospheres, enabling internal tandem catalysis at co-located active sites. NaWO induces the conversion of diffused CH and CH into reactive intermediates (CH and CH), which subsequently couple on the MnO surface to form CH and CH. Furthermore, the mesoporous channels inhibit the plasma discharge within the nanoreactor, preventing deep dehydrogenation of CH species to solid carbon. This nanoreactor demonstrates a highly selective route for the nonoxidative conversion of methane to valuable C hydrocarbons, offering a new paradigm for the rational design of catalysts for plasma-driven chemical processes.