Scientists of TIPC,CAS described a simple and environmentally friendly method for preparing highly stable dispersions of Fe₃O₄ nanoparticles with controlled morphologies in the same synthesis system for the first time. During the process, the Fe₃O₄ 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 of such Fe₃O₄ nanoparticles with various morphologies, including nanospheres, nanosheets and nanorods, is proposed. The asprepared nanoparticles show larger specific surface area and stronger magnetism, which make them perform better dye adsorption capacity and have a great potential in application of wastewater treatment.