α-Fe2O3 with Novel Double Hexagonal Pyramid-Morphology Synthesized under Dual Ion Co-work System as Anode for Lithium Ion Battery

Novel morphology of α-Fe2O3 particles with double hexagonal pyramid was synthesized via a facile hydrothermal method under the rare system of coexistence of ammonium ions (NH4+) and carbonate ions (CO32-), which is different from the previous single ion inducing system. A series of experimental results demonstrated that the synergistic effects of NH4+ and CO32- acted a decisive role in the formation process of the unique morphology, and the formation mechanism is attributed to the oriented aggregate and Ostwald ripening process. When utilized as anode materials for LIBs, the α-Fe2O3 particles with double hexagonal pyramid morphology exhibiting an excellent cycling stability of 700 mAh/g after 100 charge/discharge cycles with high coulombic efficiency of 98% start from the 25th cycle, indicating that it could be a promising alternative anode for LIBs.