Stepwise growth of hollow hexagonal -Fe₂O₃ nanocrystals

Magnetic nanocrystals have attracted much attention in various fields because of their fundamental size and shape dependent magnetism and many technological applications. In this study, hollow hexagonal Fe₂O₃ nanocrystals were synthesized using a normal hydrothermal method. A full growth evolution map of nanocrystals with different shapes was investigated to elucidate the growth mechanism. We had demonstrated the growth mechanism using the selective adsorption and dissolution theory and interestingly found that K⁺ cations were also a key point during the process of -Fe₂O₃ nanocrystals growing. At last, the magnetic properties of the hexagonal -Fe₂O₃ nanocrystals were also investigated.