The high electrical conductivity makes it possible for one-dimensional(1D)carbon materials to be used as the promising anodes for potassium ion batteries(PIBs),however,the sluggish diffusion kinetics caused by large-s...The high electrical conductivity makes it possible for one-dimensional(1D)carbon materials to be used as the promising anodes for potassium ion batteries(PIBs),however,the sluggish diffusion kinetics caused by large-sized potassium ions(K^(+))limits their practical applications in energy storage systems.In this work,hollow carbon nanorods were rationally designed as a case to verify the superiority of 1D hollow structure to improve the diffusion kinetics of K^(+).Simultaneously,edge-N(pyridinic-N and pyrrolic-N)atoms were also introduced into 1D hollow carbon structure,which can provide ample active sites and defects in graphitic lattices to adsorb K^(+),providing extra capacitive storage capacity.As expected,the optimized edge-N doped hollow carbon nanorods(ENHCRs)exhibits a high reversible capacity of 544 mAh·g^(−1)at 0.1 A·g^(−1)after 200 cycles.Even at 5 A·g^(−1),it displays a long-term cycling stability with 255 mAh·g^(−1)over 10,000 cycles.The electrochemical measurements confirm that the hollow structure is favorable to improve the transfer kinetics of K^(+)during cycling.And the theoretical calculations demonstrate that edge-N doping can enhance the local electronegativity of graphitic lattices to adsorb much more K^(+),where edge-N doping synergizes with 1D hollow structure to achieve enhanced K^(+)-storage performances.展开更多
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 in...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.展开更多
基金the National Natural Science Foundation of China(Nos.21601003,21972145,22102169,and 52172172)Natural Science Foundation of Anhui Province(No.2108085MB57)China Postdoctoral Science Foundation funded project(No.BH2340000137).
文摘The high electrical conductivity makes it possible for one-dimensional(1D)carbon materials to be used as the promising anodes for potassium ion batteries(PIBs),however,the sluggish diffusion kinetics caused by large-sized potassium ions(K^(+))limits their practical applications in energy storage systems.In this work,hollow carbon nanorods were rationally designed as a case to verify the superiority of 1D hollow structure to improve the diffusion kinetics of K^(+).Simultaneously,edge-N(pyridinic-N and pyrrolic-N)atoms were also introduced into 1D hollow carbon structure,which can provide ample active sites and defects in graphitic lattices to adsorb K^(+),providing extra capacitive storage capacity.As expected,the optimized edge-N doped hollow carbon nanorods(ENHCRs)exhibits a high reversible capacity of 544 mAh·g^(−1)at 0.1 A·g^(−1)after 200 cycles.Even at 5 A·g^(−1),it displays a long-term cycling stability with 255 mAh·g^(−1)over 10,000 cycles.The electrochemical measurements confirm that the hollow structure is favorable to improve the transfer kinetics of K^(+)during cycling.And the theoretical calculations demonstrate that edge-N doping can enhance the local electronegativity of graphitic lattices to adsorb much more K^(+),where edge-N doping synergizes with 1D hollow structure to achieve enhanced K^(+)-storage performances.
文摘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.
