In situ synthesis of Ru/RGO nanocomposites as a highly efficient catalyst for selective hydrogenation of halonitroaromatics.

A reduced graphene oxide (RGO) supported-ruthenium (Ru) catalyst was prepared through a facile hydrothermal process with reduction of Ru(3+) and GO at the same time. Small ruthenium nanoparticles were well dispersed on the surface of the RGO sheets confirmed by a set of characterizations such as SEM and TEM. XPS analysis indicated that Ru nanoparticles were in an electron-deficient state due to the electron transfer between the nanoparticles and the RGO sheets. The as-prepared catalyst was applied for the selective hydrogenation of p-chloronitrobenzene (p-CNB) to p-chloroaniline (p-CAN), exhibiting a turnover frequency (TOF) of 1800 h(-1) and a selectivity of 99.6% at complete conversion of p-CNB. The Ru/RGO catalyst displayed excellent stability and was extremely active for the hydrogenation of a series of nitroarenes, which can be ascribed to the fine dispersity of the Ru nanoparticles on the RGO sheets and their electron-deficient state.