A cheap and efficient catalyst with ultra-high activity for reduction of 4-nitrophenol

Ferromagnetic nanoparticles (NPs) prepared by conventional routes usually lead to large particle sizes because of their easy aggregation nature, and the low loading amount greatly limits their application in reduction of 4-nitrophenol (4-NP). In this contribution, well dispersed Ni nanoparticles with small diameter of 7 nm are supported on mesoporous silica SBA-15 through a facile in situ decomposition and reduction strategy. It is found that the as-prepared Ni/SBA-15 can be used as a catalyst and exhibits a high specific surface area (461 m(2) g(-1)) and ultra-high loading amount of Ni particles (574 mu g mg(-1)). The well-dispersed and high-loading Ni NPs make the Ni/SBA-15 exhibit excellent catalytic performance in 4-NP reduction, superior to any Ni NPs supported catalysts reported so far and many noble metal supported catalysts. In particular, the magnetic behaviour of Ni/SBA-15 makes it easy to recycle for reuse. This novel synthetic strategy may pave the way for the preparation of other metal nanoparticles supported on different kinds of amorphous silica with high loading capacity and high dispersion.