Ultrasmall Mo2C Nanocrystals Embedded in N-doped Porous Carbons As a Surface-Dominated Capacitive Anode for Lithium-Ion Capacitors.

In situ uniform confinement of ultrasmall Mo2C nanocrystals into micropore-enriched N-doped carbons was achieved by carbonizing phosphomolybdic acid/polyimide precursors to craft a surface-dominated capacitive battery-type anode. Upon coupling with a capacitor-type cathode, the as-fabricated lithium-ion capacitors exhibit superior power and energy outputs by improving the kinetics and capacity imbalance between two electrodes.