Gamma-ray-irradiated preparation and performance of magnetothermally responsive hybrid materials towards the tandem hydrogenation of halonitrobenzenes

Abstract

Novel magneto-thermo dual responsive organic-inorganic hybrid materials (PdCu/Fe3O4@SiO2@PNIPAM) were successfully prepared under γ-ray irradiation in this work. The γ-ray irradiation simultaneously induced the grafting of the polymer PNIPAM, and the in-situ anchoring of metallic Pd and Cu via an irradiation reduction. The catalytic performance of the prepared PdCu/Fe3O4@SiO2@PNIPAM hybrid material (abbr. PdCu/FSP) was investigated for the dehydrogenation of ammonia borane (AB) and the tandem hydrogenation of halonitrobenzenes. The results showed that the as-prepared PdCu/FSP exhibited more excellent catalytic performance in the tandem hydrogenation reaction of halonitrobenzenes in comparison with a controlled sample by a traditional preparation method. Furthermore, the PdCu/FSP catalyst prepared at a radiation dose of 25 kGy achieved excess 99 % yield of m-chloroaniline (m-CAN) at room temperature within 5 min. The PdCu/FSP hybrid material could be easily recycled by simple magnetic separation, and increasing temperature led to obvious time-shortening behavior for facile magnetic separation. Owing to lack of the intrinsic drawbacks of conventional chemical reductants and radical initiators, the gamma-ray irradiation method provides an available strategy for the construction of hybrid catalytic materials towards the hydrogenated reduction of halonitrobenzenes.