Harmonized edge/graphitic-nitrogen doped carbon nanopolyhedron@nanosheet composite via salt-confined strategy for advanced K-ion hybrid capacitors

Nitrogen doping has readily emerged as an efficient solution to boost potassium-ion storage of carbonaceous materials.Nevertheless,the capacity and lifespan enhancement of derived electrodes is still plagued by the incompetent in coordinating the dopant configurations.In the realm of emerging potassium-ion hybrid capacitor(PIHC)device,dictating nitrogen doping to enhance pseudocapacitive behavior and improve K^(+)diffusion kinetics of carbonaceous anodes is scarcely demonstrated.Herein,we report the design of hierarchical N^(-)doped carbon nanopolyhedron@nanosheet composite via a salt-confined synthetic strategy with tunable doping configurations toward advanced PIHC anode.A harmonized edge-to graphitic-nitrogen ratio in such dual-carbon materials enables outstanding rate capability(130 mAh g^(-1) at 10.0 A g^(-1))and cyclic performance(with a capacity retention of 80%after 2000 cycles at 5.0 A g^(-1))in half-cell tests.As expected,the thus-assembled PIHC full device with a working voltage of 4.2 V presents a high energy/power density(146 Wh kg^(-1)/8000 W kg^(-1))and favorable cyclicability.This work is anticipated to offer an innovative insight into the coordination of nitrogen doping configurations in heteroatom-doped carbon anode targeting highperformance PIHC applications.