Nickel and Oxygen-Containing Functional Groups Co-Decorated Graphene Shells as Catalytic Sites with Excellent Selective Hydrogenation Activity and Robust Stability

Abstract

Encapsulation of metal nanoparticles is one of the promising strategies to overcome the instability of supported metals, while improving the hydrogenation activity of multilayer graphene encapsulation remains a critical challenge. To address this issue, multilayer graphene shells (MGSs) doped with oxygen-containing functional groups (OFGs) encapsulated Ni nanoparticles catalysts (Ni@OC) were synthesized by using the calcination of Ni-based metal-organic framework method. The Ni@OC catalysts exhibited 100% nitroaromatics conversion, excellent product selectivity, and superior stability in harsh conditions. Experimental results indicated that the dissociation of H 2 and the activation of nitrobenzene compounds can be achieved with the MGSs doped by OFGs as the catalytic site in Ni@OC catalysts. In addition, OFGs intensified the electron transfer from Ni core to graphene shells and result in structural defects of the MGSs to adsorb hydrogenation substrates. Thus, a reasonable design concept was provided in improving the hydrogenation activity of MGSs encapsulated catalysts under the premise of ensuring the stable existence of metal.

Keywords: Encapsulated catalyst, Multilayer graphene shells, Oxygen-containing functional groups, Active sites, Nitroarene reduction