Realizing Selective and Aerobic Oxidation by Porous Transition-Metal-Salt@Ceria Catalyst

Abstract

In the past decades, ceria-based materials have been well developed as catalysts for complete oxidation; however, only a very few studies have involved ceria-promoted selective oxidations. Herein, porous transition-metal-salt–doped ceria (TMS@CeO2) materials (up to 455 m2/g) were fabricated by a simple, general co-assembly strategy with ionic liquids as recyclable templates. The TMS@CeO2 catalyst was found to be active in the selective oxidation of sulfides to sulfoxides/sulfones by molecular oxygen. It is interesting that the TMS doping significantly increases the catalytic performance of the original ceria catalyst and, surprisingly, the TMS@CeO2 catalyst showed much higher activity than a transition metal–doped cerium oxide solid solution. The TMS and CeO2 are supposed to synergistically activate O2 at the interface. It is believed that the abundant ceria-based materials will provide more efficient catalysts for controlled oxidation in the near future.