Magnetic Fe₃O₄ nanomaterials, possessing unique physicochemical properties such as quantum size effect, surface interfacial effect, electrical properties and magnetic properties, have attracted intensive research interest and shown potential applications in many fields (such as enviroment, energy) during the past years. In this review, some methods for preparing Fe₃O₄ in recent years are summarized, including precipitation method, thermal decomposition method, hydrothermal method, microemulsion method and sol-gel method. The advantages and disadvantages of various preparation methods are compared. As for the application of Fe₃O₄ nanomaterials, the article firstly summarizes their application as adsorbent for removal of heavy metal ions and organic pollutants from wastewater. The application of Fe₃O₄ nanomaterials in catalysis, including Fe₃O₄ nanomaterials acting active species and acting as supports for active species (such as noble metal nanoparticles, transition metal oxide, as well as metallic organic compounds) is also overviewed in detail. While applied in environment treatment and chemical catalysis, the largest advantage of Fe₃O₄ nanomaterials is that they can be easily separated by magnetic separation. Furthermore the application of Fe₃O₄ nanomaterials in energy storage (such as lithium-ion batteries and super capacitors) and biomedicine (tumor diagnosis and treatment, immobilized enzyme and immunoassay) are also discussed in brief. Finally, some problems in the preparation of Fe₃O₄ nanomaterials and their future research directions are outlined.
Contents
1 Introduction
2 Synthesis strategies of Fe₃O₄ nanomaterials
2.1 Precipitation method
2.2 Hydrothermal method
2.3 Thermal decomposition
2.4 Sol-gel method
2.5 Microemulsion method
2.6 Other methods
3 Applications of Fe₃O₄ nanomaterials
3.1 Environmental treatment
3.2 Chemical catalysis
3.3 Energy storage
3.4 Biomedical
3.5 Other applications
4 Conclusion