Core-shell MnO@MnFe2O4 Anchored by Reduced Graphene Oxide as Anode of Li-Ion Batteries Operated under Ultrawide Temperature Range

Graphical Harsh reality : A facile solution route to monodisperse MnO@3MnFe 2 O 4 @rGO is established. As anode materials of Li-ion batteries, MnO@3MnFe 2 O 4 @rGO delivers remarkable cycling performances. Therefore, MnO@3MnFe 2 O 4 @rGO nanocomposites can be considered promising battery materials that can be operated in harsh environments. A facile high-temperature solution route to a monodisperse core-shell structure of MnO (core) and MnFe 2 O 4 (shell) (abbreviated as MFO) nanoparticles anchored on reduced graphene oxide (rGO) has been established. Subsequently, MnO@MnFe 2 O 4 @rGO nanocomposites are utilized as advanced anode materials for high-performance Li-ion batteries. MnO@3MFO@rGO containing 22.5 wt% of the rGO composite (with a 1 : 3 molar ratio of MnO/MFO) as the electrodes delivered a remarkable cycling performance, that is, 587.8 mAh g −1 at a current density of 200 mA g −1 after 200 cycles at ambient temperature with an ultralow capacity fading (0.10 % per cycle). More importantly, the electrodes afforded excellent capacity stability under various operation temperatures (ca. −20 to 70 °C), such as an excellent reversible capacity of 1067 mA h g −1 at a current density of 500 mA g −1 after 300 cycles at 60 °C, and remarkable low-temperature performance of a reversible capacity of 208.7 mA h g −1 at a current density of 200 mA g −1 at −20 °C. Therefore, MnO@3MFO@rGO nanocomposites are considered as promising battery materials that can be operated in harsh environments.