Development of Highly Efficient and Durable Three-DimensionalOctahedron NiCo 2 O 4 Spinel Nanoparticles towardthe Selective Oxidation of Styrene

Herewith, we have prepared polyvinylpyrrolidone (PVP) assisted water-based synthesis of nano crystalline spinel NiCo2O4 nanocatalyst by a one-pot hydrothermal route. The formation of synthesized spinel NiCo2O4 nanoparticle has been confirmed by XRD, SEM, EDS, TEM, XPS, and EXAFS analysis respectively. The SEM results confirmed the formation of three dimension octahedron structure with an average size 20-30 nm. The EXAFS results further confirmed the spinel NiCo2O4 nanoparticles are exists in pure phase. The catalytic activity of the synthesized spinel NiCo2O4 octahedron nanoparticles was evaluated for the conversion of styrene to styrene oxide by oxidation reaction. It was found that the conversion of styrene was 78 % with 67 % of styrene oxide selectivity in presence of hydrogen peroxide as oxidant. The catalyst has also proved to be truly heterogeneity as it doesn’t loss its phase and catalytic activity even after five consecutive cycle.