摘要
Bismuth has drawn widespread attention as a prospective alloying-type anode for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its large volumetric capacity.However,such material encounters drastic particle pulverization and overgrowth of solid-electrolyte interphase(SEI)upon repeated(de)alloying,thus causing poor rate and cycling degradation.Herein,we report a unique structure design with bismuth nanorods confined in hollow N,S-codoped carbon nanotubes(Bi@NS-C)fabricated by a solvothermal method and in-situ thermal reduction.Ex-situ SEM observations confirm that such a design can significantly suppress the size fining of Bi nanorods,thus inhibiting the particle pulverization and repeated SEI growth upon charging/discharging.The as achieved Bi@NS-C demonstrates outstanding rate capability for SIBs(96.5%capacity retention at 30 A g^(-1) vs.1 A g^(-1)),and a record high rate performance for PIBs(399.5 m Ah g^(-1)@20 A g^(-1)).Notably,the as constructed full cell(Na_(3)V_(2)(PO_(4))_(3)@C|Bi@NS-C)demonstrates impressive performance with a high energy density of 219.8 W h kg^(-1) and a high-power density of 6443.3 W kg^(-1)(based on the total mass of active materials on both electrodes),outperforming the state-of-the-art literature.
基金
supported by the National Natural Science Foundation of China(22179077,51774251)
the Shanghai Science and Technology Commission’s"2020 Science and Technology Innovation Action Plan"(20511104003)
the Natural Science Foundation in Shanghai(21ZR1424200)
the Hebei Natural Science Foundation for Distinguished Young Scholars(B2017203313)
the Scientific Research Foundation for the Returned Overseas Chinese Scholars(CG2014003002)。