Green synthesis of Fe 3 O 4 nanoparticles with controlled morphologies using urease and their application in dye adsorption

This paper describes a simple and environmentally friendly method for the preparation of highly stable dispersions of Fe 3 O 4 nanoparticles with controlled morphologies, in the same synthesis system for the first time. During the process, the Fe 3 O 4 nanoparticles are formed using urease as a multifunctional reagent, including catalyst, template and dispersant, due to its enzymatic activity and special enzymatic steric structure. A possible formation mechanism for these Fe 3 O 4 nanoparticles, which have various morphologies including nanospheres, nanosheets and nanorods, is proposed. The as-prepared nanoparticles show a larger specific surface area and a stronger magnetism, which enhances their dye adsorption capacity and increases their potential for application in wastewater treatment.