Hollow mesoporous hetero-ZnO/ZnMnO 3 microspheres: template-free formation process and enhanced lithium storage capability towards Li-ion batteries as a competitive anode

Hierarchical hollow porous structures have attracted enormous attention in the field of emerging electrochemical energy storage. Spinel ZnMnO 3 stands out from other metal oxide-based anodes thanks to its affordability, environmental friendliness, safety and large capacity. However, its modestly high-rate capability and cycling stability should be addressed for advanced Li-ion batteries (LIBs) via smartly engineering the electrode structures/components using simple strategies. In this contribution, we devised a scalable bottom-up methodology for the fabrication of hollow mesoporous ZnO/ZnMnO 3 (ZZMO) microspheres. The underlying template-free formation mechanism was rationally proposed. Benefiting from synergistic contributions from the bi-component-active ZnO–ZnMnO 3 hetero-structure at the nanoscale, hollow and mesoporosity, the resultant hollow ZZMO microspheres were endowed with a large reversible capacity of ∼695 mA h g −1 at 1 A g −1 , as well as stable cycling performance and a remarkable rate capability when utilized as a competitive anode for LIBs. Furthermore, the quantitative analysis demonstrates that the main faradaic capacitive contribution accounts for the outstanding lithium storage of the ZZMO anode. Promisingly, the LiNi 0.8 Co 0.1 Mn 0.1 O 2 //ZZMO full battery achieved a capacity of ∼121.0 mA h g −1 at 0.1 A g −1 , and energy density of ∼188.6 W h kg −1 . More significantly, these results highlight that hollow porous ZZMO microspheres would be a promising low-cost anode for next-generation LIBs.