Gu Zhen-Yi, Cao Jun-Ming, Guo Jin-Zhi, Wang Xiao-Tong, Zhao Xin-Xin, Zheng Shuo-Hang, Sun Zhong-Hui, Yang Jia-Lin, Zhang Kai-Yang, Liang Hao-Jie, Li Kai, Wu Xing-Long
Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, c/o MOE Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Guangzhou University, Guangzhou 510006, Guangdong, P. R. China.
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
J Am Chem Soc. 2024 Feb 21;146(7):4652-4664. doi: 10.1021/jacs.3c11739. Epub 2024 Jan 24.
Since sodium-ion batteries (SIBs) have become increasingly commercialized in recent years, NaV(PO)OF (NVPOF) offers promising economic potential as a cathode for SIBs because of its high operating voltage and energy density. According to reports, NVPOF performs poorly in normal commercial poly(vinylidene fluoride) (PVDF) binder systems and performs best in combination with aqueous binder. Although in line with the concept of green and sustainable development for future electrode preparation, aqueous binders are challenging to achieve high active material loadings at the electrode level, and their relatively high surface tension tends to cause the active material on the electrode sheet to crack or even peel off from the collector. Herein, a cross-linkable and easily commercial hybrid binder constructed by intermolecular hydrogen bonding (named HPP) has been developed and utilized in an NVPOF system, which enables the generation of a stable cathode electrolyte interphase on the surface of active materials. According to theoretical simulations, the HPP binder enhances electronic/ionic conductivity, which greatly lowers the energy barrier for Na migration. Additionally, the strong hydrogen-bond interactions between the HPP binder and NVPOF effectively prevent electrolyte corrosion and transition-metal dissolution, lessen the lattice volume effect, and ensure structural stability during cycling. The HPP-based NVPOF offers considerably improved rate capability and cycling performance, benefiting from these benefits. This comprehensive binder can be extended to the development of next-generation energy storage technologies with superior performance.
近年来，随着钠离子电池（SIBs）日益商业化，NaV(PO)OF（NVPOF）因其高工作电压和能量密度，作为SIBs的阴极具有可观的经济潜力。据报道，NVPOF在普通商业聚偏氟乙烯（PVDF）粘结剂体系中性能不佳，与水性粘结剂结合时性能最佳。尽管水性粘结剂符合未来电极制备绿色可持续发展的理念，但在电极层面实现高活性材料负载具有挑战性，且其相对较高的表面张力往往会导致电极片上的活性材料开裂甚至从集流体上剥落。在此，一种通过分子间氢键构建的可交联且易于商业化的混合粘结剂（命名为HPP）已被开发并应用于NVPOF体系，这使得在活性材料表面生成稳定的阴极电解质界面成为可能。根据理论模拟，HPP粘结剂提高了电子/离子导电性，大大降低了Na迁移的能垒。此外，HPP粘结剂与NVPOF之间强烈的氢键相互作用有效防止了电解质腐蚀和过渡金属溶解，减轻了晶格体积效应，并确保了循环过程中的结构稳定性。基于HPP的NVPOF受益于这些优势，具有显著改善的倍率性能和循环性能。这种综合粘结剂可扩展到高性能下一代储能技术的开发。
