Bubble-templated synthesis of Fe2(MoO4)3 hollow hierarchical microsphere with superior low-temperature behavior and high areal capacity for lithium ion batteries

Abstract

The exploration of earth-abundant electrode materials with superior low-temperature behavior and high areal capacity have become more and more urgent for the field of electric vehicles and portable electronic devices. Hollow hierarchical microstructure composed of nanoscaled subunits holds great potential in developing novel electrode materials with superior electrochemical performance. Herein, we demonstrate a bubble-templated method to synthesize Fe2(MoO4)3 hollow microspheres, and the formation mechanism is carefully investigated. When evaluated as the lithium-ion battery anode, they exhibit a high reversible capacity of 1205 mA h g−1 at 0.5 A g−1 after 200 cycles, good rate performance of 565 mA h g−1 at 10 A g−1, excellent low temperature capability of 281 mA h g−1 at 1 A g−1 at −20 °C, and high reversible areal discharge capacity of 5.2 mA h cm−2 with a high active material mass loading of 5 mg cm−2. Additionally, the full cell assembled with activated Fe2(MoO4)3 hollow microspheres negative electrode and LiFePO4 positive electrode exhibits a high reversible capacity of 1115 mA h g−1 at 0.2 A g−1. Furthermore, in situ X-ray diffraction analysis is applied to clarify the electrochemical reaction mechanism during the discharge/charge process.