Abstract
Na batteries(SIBs)have been emerging as the most promising candidate for the next generation of sec-ondary batteries.However,the development of high-performance and cost-effective anode materials is urgently needed for the large-scale applications of SIBs.In this study,carbon dots confined bimetallic sulfide(NiCo2S4)architecture(NiCo2S4@CDs)was proposed and synthesized from assembling nanosheets into cross-stacked superstructure and the subsequent confinement of carbon dots.This novel decussated structure assembly from nanosheets is greatly beneficial to the structure stability of electrode material during the successive charge/discharge processes.Besides,the CDs based carbon conductive network can enhance the electrical conductivity for facilitating the easy transport of electron/Na.Benefitting from these advantages,NiCo2S4@CDs exhibits high-rate performance and an ultralong cycling life in SIBs.Specifically,the specific capacity of NiCo2S4@CDs can reach the discharge specific capacity as high as 568.9 mAh/g at 0.5 A/g,which can also maintain 302.7 mAh/g after 750 cycles at 5.0 A/g.Additionally,ex-situ characterization techniques such as ex-situ XRD and ex-situ XPS were employed to further explore the sodium storage mechanism of the NiCo2S4@CDs anode.
基金项目
National Natural Science Foundation of China(52101243)
Natural Science Foundation of Guangdong Province(2023A1515012619)
Science and Technology Planning Project of Guangzhou(202201010565)
万方数据