Metal–Organic Framework (MOF) Derived Electrodes with Robust and Fast Lithium Storage for Li‐Ion Hybrid Capacitors

Abstract

Hybrid metal–organic frameworks (MOFs) demonstrate great promise as ideal electrode materials for energy-related applications. Herein, a well-organized interleaved composite of graphene-like nanosheets embedded with MnO2 nanoparticles (MnO2@C-NS) using a manganese-based MOF and employed as a promising anode material for Li-ion hybrid capacitor (LIHC) is engineered. This unique hybrid architecture shows intriguing electrochemical properties including high reversible specific capacity 1054 mAh g−1 (close to the theoretical capacity of MnO2, 1232 mAh g−1) at 0.1 A g−1 with remarkable rate capability and cyclic stability (90% over 1000 cycles). Such a remarkable performance may be assigned to the hierarchical porous ultrathin carbon nanosheets and tightly attached MnO2 nanoparticles, which provide structural stability and low contact resistance during repetitive lithiation/delithiation processes. Moreover, a novel LIHC is assembled using a MnO2@C-NS anode and MOF derived ultrathin nanoporous carbon nanosheets (derived from other potassium-based MOFs) cathode materials. The LIHC full-cell delivers an ultrahigh specific energy of 166 Wh kg−1 at 550 W kg−1 and maintained to 49.2 Wh kg−1 even at high specific power of 3.5 kW kg−1 as well as long cycling stability (91% over 5000 cycles). This work opens new opportunities for designing advanced MOF derived electrodes for next-generation energy storage devices.