Magnetically recyclable nanocatalyst with synergetic catalytic effect and its application for 4-nitrophenol reduction and Suzuki coupling reactions

Abstract

Magnetically recyclable catalysts with high activity are highly desired in heterogeneous catalysis, as their magnetic nature allows the facile and efficient separation under an external magnetic field. We developed a facile method to fabricate a new type of recyclable nanocatalyst based on double-shelled hollow nanospheres (HNSs) supported Pd nanoparticles (NPs), in which magnetic Fe species were served as inner shell and nitrogen doped carbon (NC) as outer shell. The resultant Fe@NC@Pd HNSs possess unique hollow structure and mesoporous shells for facile mass transportation, magnetic inner shell for easy recycling and well dispersed Pd NPs for high-density of catalytic sites. The magnetic Fe-based inner shell, catalytically active outer NC shell combined with ultrafine Pd NPs synergistically enhanced the catalytic activity and recyclability in organocatalysis. In 4-nitrophenol reduction reaction, the turnover frequency (TOF) of Fe@NC@Pd catalyst is up to 370.3 min−1, which is one of the highest efficiencies ever reported. Furthermore, Fe@NC@Pd can also be applied for Suzuki coupling reaction with the TOF as high as 52.7 min−1.