Multidimensional Dual-Carbon Skeleton Network Confined MnOx Anode Boosting High-Performance Lithium-Ion Hybrid Capacitors

Manganese oxide with high theoretical specific capacity and intermediate reaction plateau is a promising anode candidate for lithium-ion hybrid capacitors (LIHCs). However, the sluggish kinetics and severe volume expansion have seriously hindered its practical progress. Herein, a mixedvalence manganese oxide confined by a dual-carbon skeleton network (MnOx@C-R) was successfully prepared. Owing to the synergistic effect of the introduction of the dual-carbon skeleton-network structure in a reducing atmosphere, the reasonable pore size distribution, crystallinity, and phase composition have been optimized. The material exhibits excellent lithium storage performance (778.2 mA h g(-1) after 10 cycles at 0.1 A g(-1)), along with excellent rate performance (141.7 mA h g(-1) at 5 A g(-1)) and stable cycling ability (402.4 m Ah g(-1) for 1000 cycles at 1 A g(-1)). Moreover, further characterization displayed the change of the valence state of manganese during the charging/discharging, revealing the source of the excellent electrochemical performance of MnOx@C-R. Therefore, LIHCs were assembled using a MnOx@C-R anode and the activated carbon network with excellent energy density (151 Wh kg(-1)) and amazing power density (21.9 kW kg(-1)). This work supplies an alternative strategy for optimizing the lithium storage performance of manganese oxide.