Mild aqueous synthesis of octahedral Mn3O4 nanocrystals with varied oxidation states

▶ Octahedral Mn3O4 nanocrystals were prepared by a simple aqueous method. ▶ The size and shape were controlled by the reaction time. ▶ The reaction velocity can be manipulated by PEG and temperature. ▶ The oxide composition of Mn3O4 vaied with H/Mn ratios.