The catalytic evaluation of in situ grown Pd nanoparticles on the surface of Fe 3 O 4 @dextran particles in the p-nitrophenol reduction reaction

We report the catalytic activity evaluation of in situ grown Pd nanoparticles on the surface of superparamagnetic Fe 3 O 4 particles coated with the natural polymer dextran, in the reduction of p -nitrophenol (Nip), in water, by sodium borohydride. The catalyst was fully characterized; its activity evaluated through kinetic studies and compared with recently reported catalysts using a new activity parameter. Applying a pseudo-monomolecular surface reaction approach, the reaction was also investigated by means of a theoretical adsorption model, which revealed that the reaction follows the Langmuir–Hinshelwood mechanism, where both molecules adsorb on the catalyst surface prior to undergoing a bimolecular reaction. Moreover, the catalyst could be reused five times without significant loss of Pd and with a high degree of Nip conversion.