Application of NiCo2O4 as a catalyst in the conversion of p-nitrophenol to p-aminophenol

Transition metal containing spinel structure type oxides exhibit characteristic structural, electrical, magnetic and catalytic properties. Present work investigated a novel application of nickel and cobalt containing spinel oxide (NiCo2O4) in the conversion of p-nitrophenol to p-aminophenol. The oxide compound was synthesized by citrate gel method and characterized by powder X-ray diffraction method and scanning electron microscopy. The conversion process involved room temperature hydrogenation of p-nitrophenol by aqueous sodium borohydride. Powder nickel cobalt oxide was used as a catalyst. The reduction of p-nitrophenol has been monitored by UV-VIS and IR spectroscopic analysis. Complete conversion of the nitro compound to amino compound was achieved within a minute. (C) 2008 Elsevier B.V. All rights reserved.