Investigation of ion diffusion in polyethylene oxide-based solid electrolyte with functionalized La(OH)3 nanofibers for high-rate all-solid-state lithium-metal batteries.

作者：Shanshan Song, Yijun Gao, Linbo Cao, H. Park, Zhiliang Liu, Fei He, Wenwu Li, Meilin Liu, Piaoping Yang · 发表于：Journal of Colloid and Interface Science · 年份：2025 · DOI：10.1016/j.jcis.2025.137589 · 研究领域：Medicine

Solid polymer electrolytes have emerged as promising materials for next-generation lithium metal batteries due to their enhanced safety and high energy density potential. However, their widespread adoption is hindered by slow ion transport and inefficient lithium-ion (Li+) selectivity. To overcome these limitations, this study introduces a composite electrolyte by incorporating functionalized La(OH)3 nanofibers with oxygen vacancies into a Poly(ethylene oxide) (PEO) matrix. These nanofibers, synthesized via a simple method, are designed to improve Li+ mobility by leveraging their oxygen vacancies to immobilize TFSI- anions from the bis(trifluoromethanesulfonyl)imide (LiTFSI). Simultaneously, amino groups on the nanofiber surface act as binding sites, facilitating lithium salt dissociation and creating supplementary ion transport pathways. Density functional theory (DFT) and molecular dynamics (MD) simulations reveal that the functionalized La(OH)3 nanofibers effectively suppress TFSI- anion movement while reducing the energy barrier for Li+ migration. This mechanism elevates the Li+ transference number to 0.51, a significant improvement over the conventional PEO-based electrolytes. The composite electrolyte exhibits excellent performance in Li||Li cells, maintaining stable cycling for over 600 h at a current density of 0.38 mA cm-2. Furthermore, a solid-state LiFePO4||Li battery demonstrates highly reversible capacities of 100.2 mAh g-1 after 600 cycles at 8C. By combining an...