NASICON-(Na superionic conductor-)based solid-state electrolytes(SSEs)are believed to be attracting candidates for solid-state sodium batteries due to their high ionic conductivity and prospectively reliable stability...NASICON-(Na superionic conductor-)based solid-state electrolytes(SSEs)are believed to be attracting candidates for solid-state sodium batteries due to their high ionic conductivity and prospectively reliable stability.However,the poor interface compatibility and the formation of Na dendrites inhibit their practical application.Herein,we directly observed the propagation of Na dendrites through NASICON-based Na3.1Zr2Si2.1P0.9O12 SSE for the first time.Moreover,a fluorinated amorphous carbon(FAC)interfacial layer on the ceramic surface was simply developed by in situ carbonization of PVDF to improve the compatibility between Na metal and SSEs.Surprisingly,Na dendrites were effectively suppressed due to the formation of NaF in the interface when molten Na metal contacts with the FAC layer.Benefiting from the optimized interface,both the Na||Na symmetric cells and Na3V2(PO4)3||Na solidstate sodium batteries deliver remarkably electrochemical stability.These results offer benign reference to the maturation of NASICON-based solid-state sodium batteries.展开更多
基金the National Key Technologies R&D Program,China(2016YFB0901500)the Opening Project of Key Laboratory of Optoelectronic Chemical Materials and Devices,Ministry of Education,Jianghan University(JDGD-201703)+2 种基金the National Natural Science Foundation of China(51725206)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA21070500)Youth Innovation Promotion Association,Chinese Academy of Sciences(2020006).
文摘NASICON-(Na superionic conductor-)based solid-state electrolytes(SSEs)are believed to be attracting candidates for solid-state sodium batteries due to their high ionic conductivity and prospectively reliable stability.However,the poor interface compatibility and the formation of Na dendrites inhibit their practical application.Herein,we directly observed the propagation of Na dendrites through NASICON-based Na3.1Zr2Si2.1P0.9O12 SSE for the first time.Moreover,a fluorinated amorphous carbon(FAC)interfacial layer on the ceramic surface was simply developed by in situ carbonization of PVDF to improve the compatibility between Na metal and SSEs.Surprisingly,Na dendrites were effectively suppressed due to the formation of NaF in the interface when molten Na metal contacts with the FAC layer.Benefiting from the optimized interface,both the Na||Na symmetric cells and Na3V2(PO4)3||Na solidstate sodium batteries deliver remarkably electrochemical stability.These results offer benign reference to the maturation of NASICON-based solid-state sodium batteries.