Morphology control of α-Fe₂O₃ towards super electrochemistry performance

α-Fe₂O₃ with various morphologies including spindle, rod, tube, disk, and ring were synthesized through controlling the H₂PO₄ ^- etching process. The concentrations of H₂PO₄ ^- plays an important role in controlling the morphology change of the samples. Selected adsorption of H₂PO₄ ^- ions resulted in anisotropic growth. In addition, the etching of H₂PO₄ ^- occurred in the center of rods which resulted in tubal α-Fe₂O₃. Nanodiscs were created once the etching process occurred on the wall of the tube. The electrochemical test shows that disklike samples revealed excellent specific capacitance, rate capacity and cycling stability because of relative higher surface area and pore structure. For the CO catalytic oxidation properties, spindle samples exhibited super catalytic activity.