摘要
The development of high-voltage sodium metal batteries faces significant challenges,including high desolvation energy and detrimental interfacial side reactions at elevated voltages.These issues critically impede Na^(+) transport kinetics and compromise high voltage stability,but can be addressed by strategically modifying the Na^(+) solvation structure.Herein,we report a metal-organic framework(MOF)-based strategy to reconfigure the Na^(+) solvation structure specifically for enhanced high-voltage stability and Na^(+) transport.A composite gel polymer electrolyte(MPVHF) is engineered by incorporating UiO-66-(COONa)_(2) into a polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP) matrix,followed by liquid electrolyte infiltration.The densely arrayed carboxylate groups(-COO^(-)) on the MOF ligands exert strong electrostatic interactions with Na^(+),effectively weakening the coordination bonds between Na^(+) and solvent molecules.This targeted solvation regulation significantly mitigates interfacial side reactions and promotes the formation of a robust,stable electrode-electrolyte interphase crucial for high-voltage operation.Consequently,the MPVHF electrolyte achieves a wide electrochemical stability window extending to 4.93 V and a high Na^(+) transference number of 0.74.The Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)‖Na full cells employing MPVHF exhibit stable cycling at 4.5 V cut-off for 1300 cycles at 4 C.This work presents an effective approach to tailor Na^(+) coordination and transport for high-voltage and fast-charging sodium metal batteries.
基金
supported by the National Natural Science Foundation of China (22325802,U22A20417)
the Natural Science Foundation of Guangdong Province (2024A1515012535, 2025A1515010316)
the Guangdong Basic and Applied Basic Research Foundation (2023B1515120005)
the Guangdong Major Project of Basic and Applied Basic Research (2023B0303000002)
the Science and Technology Program of Guangzhou (2023B03J1281)
the State Key Laboratory of Catalysis (2024SKLA-009)
the Energy Revolution S&T Program of Yulin Innovation Institute of Clean Energy (E411120705)。
