▎ 摘　　要

Lithium-ion capacitors (LICs) are a potential bridge between conventional Li-ion batteries (LIBs) with high energy density and capacitors with high power density. In this work, we demonstrate high energy, power, and cycle life LICs with anodes based on palladium nanoparticle-decorated reduced graphene oxide (rGO@Pd) and activated carbon (AC)-based cathodes. Aqueous LiNO3 solution has been employed as electrolyte due to its superior safety characteristics and environmental friendliness. GO was prepared by modified Hummers' method, and rGO@Pd was subsequently synthesized by facile hydrothermal reduction with PdCl2. Electrodes were fabricated by drop casting additive-free rGO@Pd and AC slurry on carbon paper current collectors. Scanning electron microscopy with energy dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction as well as Raman spectroscopy have been used to characterize the developed materials. We were able to show successful Pd nanoparticle formation and uniform distribution in the composite. The prepared electrodes have been used to construct CR2032 coin cell LICs the performance of which was evaluated by 2-electrode cyclic voltammetry and galvanostatic charge-discharge with 1 M LiNO3 electrolyte. The LICs exhibited excellent electrochemical performance with specific capacitance of 188.6 F g(-1) and energy and power densities of 51.3Wh kg(-1) and 46.5 kW kg(-1) at a current of 1 A g(-1). The capacitors retained 95.3% of initial capacitance after 10,000 charge-discharge cycles.