摘要
Although Li–S batteries have a high theoretical capacity,their application are significantly hindered by the complex shuttle effect of polysulfides.To address the issues,in this paper,Ni_(2)V_(2)O_(7) prepared by a simple method is proposed as an efficient catalyst for S cathodes.Ni_(2)V_(2)O_(7) composed of Ni–O octahedra and V–O tetrahedra has a specific electronic structure.The Ni and V atoms interacted,enabling a fast kinetics of polysulfide redox.Moreover,Ni_(2)V_(2)O_(7) contains metal sites(Ni and V)and oxygen vacancies,providing a high adsorption capacity and abundant active sites for polysulfide redox.Therefore,Li–S batteries consisting of Ni_(2)V_(2)O_(7)-based cathodes exhibit an excellent cycling stability with a capacity of 1061 mAh g^(−1) and capacity retention of 87.6%after 150 cycles at 0.2 C.Moreover,at 1 C rate,the batteries exhibit a capacity of 706 mAh g^(−1) after 300 cycles with a minimal capacity decay of only 0.08%per cycle.
基金
support from Guangdong Provincial Key Laboratory of Materials and Technology for Energy Conversion(Grant No.MATEC2023KF010)
Guangdong Basic,Applied Basic Research Foundation(Grant No.2022A1515010015).
