Nanostructured biogel templated synthesis of Fe3O4 nanoparticles and its application for catalytic degradation of xylenol orange
Abstract
Easy preparation of well-dispersed inorganic nanoparticles is critical for their practical applications. By using jellyfish mesoglea, a biological hydrogel mainly composed of nanofibers, as a template, nanocomposite hydrogels with well-dispersed Fe3O4 nanoparticles are successfully synthesized through the co-precipitation method. Fe3O4 nanoparticles, mostly less than 20 nm, are uniformly formed and distributed on the nanofibers. With the increase of Fe2+/Fe3+ concentration, more nanoparticles are formed and hence the size of the nanofibers increases, and only very less significant aggregation of Fe3O4 nanoparticles is observed at a high Fe2+/Fe3+ concentration of 1 M. The JF/Fe3O4 nanocomposite hydrogels have very high Fe3O4 content, which can achieve about 79%. The nanocomposite hydrogels display nearly superparamagnetism, and show smaller saturation magnetizations (Ms) than that of bulk Fe3O4. Moreover, introduction of Fe3O4 nanoparticles increases the BET surface areas of the gels. The JF/Fe3O4 nanocomposite hydrogels exhibit high activity in catalyzing the oxidative degradation of xylenol orange and excellent reusability.