Pd-ZIF-L-GO ternary nanolaminates for enhanced heterogeneous catalysis

A novel sheet-on-sheet Pd-ZIF/GO (Pd/ZG) catalyst is synthesized by constructing ZIF-L with GO and PVP-Pd nanoparticles (NPs) via a facile in situ method. The in situ introduction of GO promotes the formation of ZIF-L, leading to a higher yield of Pd/ZG, about three times higher than Pd/ZIF-L. We ascribe this to the possible interaction of the oxygen-containing groups on the GO surface with the Zn²⁺ cations in ZIF nodes and the PVP wrapped on the Pd surface, resulting in the formation of sheet-on-sheet Pd-ZIF/GO with good Pd dispersion. The Pd/ZG shows superior catalytic performance in the reduction of nitroarenes, and its turnover frequency (TOF) value is five times higher than Pd/ZIF-L. The superior catalytic activity can be ascribed to the uniformly dispersed tiny Pd NPs between ZIF-L and GO nanosheets, fast mass transfer in porous structure, and excellent electron conductivity due to strong interactions among ZIF-L, GO and PVP-Pd. These findings provide new opportunities for rational design of catalysts and their applications in the reduction of nitroarenes, important processes for industrial synthesis of pesticides, dyes, medicines, etc.