MIL-101 supported nanoparticle catalysts : synthesis, characterization and catalytic properties

Abstract

Highly active, robust and stable bimetallic NiPd, CuPd and CoPd alloy nanoparticle catalysts stabilized by MIL-101 framework, (M/Pd atomic ratio = 95:5, M = Ni, Cu and Co) were synthesized and their catalytic activity for Suzuki reaction at moderate reaction conditions was explored. In contrary to monometallic counterparts, a significant enhancement in catalytic activity was observed with these bimetallic NiPd/MIL-101, CuPd/MIL-101 and CoPd/MIL-101 alloy nanoparticle catalysts. Among the synthesized catalysts, NiPd/MIL-101 and CuPd/MIL-101 displayed higher catalytic activity for the synthesis of biaryls for a wide range of substituted aryl halides and arylboronic acids having electron donating and electron withdrawing substituents, whereas CoPd/MIL-101 was found to be poorly active. Catalytic efficiency of the synthesized CuPd/MIL-101 was found to be highest followed by NiPd/MIL-101, whereas CoPd/MIL-101 was found to be poorly active for Suzuki reaction. The observed high catalytic activity displayed by NiPd/MIL-101 and CuPd/MIL-101 was attributed to the synergistic effect brings in by electronic charge transfer from Ni or Cu to Pd, and high dispersity of NiPd and CuPd nanoparticles on MIL- 101.