Hierarchical MOF-Hybridized Bifunctional Polyarylether Nitrile Porous Separator for High Safety and Long-Life Lithium Metal Batteries

作者：Yu Zheng, Lin Guo, Liang He, Jiajia Ye, Jinghui Zhang, Lifen Tong, Shuning Liu, Xiaobo Liu · 发表于：ACS Sustainable Chemistry & Engineering · 年份：2025 · DOI：10.1021/acssuschemeng.5c09915 · 被引用次数：4 · 研究领域：Advanced Battery Materials and Technologies、Extraction and Separation Processes、Advancements in Battery Materials

Ensuring safety and reliability in lithium metal batteries (LMBs) requires advanced separators with precisely tailored architectures and interfacial functionalities. Herein, we develop a hierarchically structured MOF/carboxylated poly(arylene ether nitrile) (CPEN) composite separator through a dual-region in situ coordination strategy. Systematic investigation of MOF growth within and on CPEN elucidated the structure–performance evolution and identified parameters for synergistic dendrite suppression and pore structure optimization. Building on this understanding, hierarchical MOF growth was achieved both internally and externally, synchronously tailoring the pore architecture and interfacial chemistry of the hierarchical design separators. A hierarchical design is realized by constructing and comparing three types of separators: internal-only (I-CPEN), surface-only (S-CPEN), and dual-growth architectures (I/S-CPEN). The dual-growth I/S-CPEN separator combines internal pore-size control with interfacial modulation, resulting in directional ion transport and effective dendrite suppression. It achieves an ionic conductivity of 2.02 mS·cm –1, a lithium-ion transference number of 0.78, and long-term cycling stability with 94.95% capacity retention over 500 cycles at 0.5 C. Experimental results combined with DFT simulations demonstrate that the MOF framework not only preserves efficient Li + transport but also enables spatial separation and dynamic regulation of anions and cations...