Soft template-induced deep pore structure of Cu/Al2O3 for promoting plasma-catalyzed CO2 hydrogenation to DME

Plasma-activated heterogeneous catalysis is a promising strategy for catalytic CO 2 hydrogenation under mild conditions. In this study, pore structures with deep pore channels were constructed on Al 2 O 3 - x via a soft template method, and Cu/Al 2 O 3 - x was prepared by an impregnation method, with Al 2 O 3 - x serving as the support for plasma-catalyzed CO 2 hydrogenation to dimethyl ether (DME). Cu/Al 2 O 3 -0.75/HZSM-5 demonstrated a high performance and discharge efficiency for plasma-catalyzed CO 2 hydrogenation. The CO 2 conversion and DME yield for plasma-catalyzed CO 2 hydrogenation on Cu/Al 2 O 3 -0.75/HZSM-5 reached 21.98% and 9.83%, respectively, with selectivities for CO, CH 3 OH, and DME on Cu/Al 2 O 3 -0.75/HZSM-5 of 25.39%, 29.89%, and 44.72%, respectively. The deep pore structures on Al 2 O 3 - x serve as Cu loading sites, and the confinement effect of the pores enhances the metal-support interaction and Cu metal dispersion. More abundant and stronger Brønsted basic and Lewis acidic sites facilitate the activation and hydrogenation of CO 2 . Notably, the electric field formed by Cu sites anchored in the deep pore channel structures is conducive to guiding the activated plasma CO 2 intermediates into the difficult-to-access pores for hydrogenation. Hydrogenation of the plasma-activated CO 2 intermediates in the deep pore channels is crucial for improving plasma-catalyzed CO 2 hydrogenation to DME. The deep pore structures via a soft template method provide the Cu sites in deep channels, which generates an electric field under the plasma to promote the hydrogenation of the intermediate in the pore, thus enhancing the efficiency of plasma-catalyzed CO 2 hydrogenation to DME. • The deep pore structure is constructed in Al 2 O 3 by a soft template. • The deep pore structure provides the anchoring sites of Cu. • The plasma CO 2 intermediates are induced by the electric field of Cu in the pore. • Hydrogenation in the pore is crucial for boosting plasma CO 2 catalytic to DME.