Encapsulated Cobalt Oxide on Carbon Nanotube Support as Catalyst for Selective Continuous Hydrogenation of the Showcase Substrate 1‐Iodo‐4‐nitrobenzene
A carbon nanotube supported catalyst containing cobalt/cobalt oxide (Co/Co3O4) nanoparticles encapsulated within a shell of nitrogen‐doped graphene layers (Co3O4/NGr@CNT) was prepared. It shows excellent chemoselectivity in the hydrogenation of 1‐iodo‐4‐nitrobenzene, which contains an iodine substituent highly sensitive against hydrodehalogenation. In contrast to traditional activated charcoal‐supported catalysts such as Pt‐V/C or the closely related Vulcan carbon black supported Co3O4/NGr@C, the advantageous morphological properties of the CNT support allow for the application of the new Co3O4/NGr@CNT as a fixed bed catalyst in a continuous flow reactor. Under optimized conditions, no dehalogenation side products could be detected. This remarkable selectivity in combination with its mechanical stability under operation conditions render Co3O4/NGr@CNT a catalyst particularly relevant for application in continuous processes based on a packed bed reactor.