Highly efficient Zn-MOF derived Carbon-Nitrogen material based catalyst for nitroaromatic Hydrogenation: The role of Zn-O-C bond and Pyridinic-N

Abstract

Zn-based catalysts have great feature of environmental friendliness and developmental potential to replace precious metals in heterogeneous catalytic hydrogenation. In this work, a porous CN material-based catalysts containing trace Zn were prepared by high-temperature pyrolysis using zeolitic imidazolate framework (ZIF-8) material as precursor. The result shows that (Zn)NC-800 and (Zn)NC-600–700 exhibit outstanding hydrogenation ability and good stability in nitro compounds hydrogenation reaction. Based on the results of characterization and DFT calculations, two hydrogenation active sites complete the hydrogenation of nitro compounds in (Zn)NC-800 and (Zn)NC-600–700: the residual trace Zn in the form of Zn-O-C bond can activate the CN structure and promote the conversion of nitrobenzene; the pyridinic-N is confirmed to accelerate the electron transfer and enhance the selectivity to aniline. This work has an enlightening significance for the efficient development of heterogeneous catalytic hydrogenation catalysts.