发表机构
Ludwig-Maximilians-Universität München; Drexel University; University of North Texas; ESRF, The European Synchrotron; Universitat Politècnica de Catalunya (UPC)（慕尼黑大学; 德雷塞尔大学; 北德克萨斯大学; 欧洲同步辐射光源; 加泰罗尼亚理工大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究结合原位显微技术与同步辐射X射线衍射，揭示MXenes经循环后形成的结构记忆，明确了其层间嵌入行为的动力学差异与电极尺度的结构演化规律。
AI 中文摘要
离子嵌入可实现层状固体中电荷、结构与功能的可逆调控，但层状材料包含不同厚度与堆叠方式的纳米片，其嵌入路径在整体测量中被平均化，在埃级限域下尤为关键——此时离子传输与溶剂重组、宿主变形耦合，导致动力学、可逆性及活化的起源尚不明确。本研究结合原位干涉散射与干涉反射显微技术，解析单个单层及多层Ti₃C₂Tₓ MXene薄片中质子驱动的动力学，表明仅几层堆叠就会引入显著的动力学势垒；循环后纳米片分化为三种持久行为：可逆单层、堆叠多层（恢复不完全且脱嵌延迟）、相干堆叠多层（通过可逆折叠自稳定）。原位同步辐射X射线衍射在电极尺度证实该记忆，层间结构收敛至可重复状态。本研究揭示了调控MXenes后续嵌入的循环诱导结构记忆。
英文摘要
Ion intercalation enables reversible control of charge, structure and function in layered solids. Yet layered materials contain nanosheets with different thicknesses and stacking, whose intercalation pathways are averaged out in ensemble measurements. This becomes critical under Angstrom-scale confinement, where ion transport couples to solvent reorganization and host deformation, leaving the origins of kinetics, reversibility and activation unresolved. Here we combine operando interferometric scattering and interference reflection microscopy to resolve proton-driven dynamics in individual single- and multilayer Ti3C2Tx MXene flakes and show that even a few stacked layers introduce a significant kinetic barrier. Cycling then separates nanosheets into three persistent behaviors: reversible monolayers, restacked multilayers with incomplete recovery and delayed deintercalation, and coherently stacked multilayers that self-stabilize through reversible folding. Operando synchrotron X-ray diffraction shows this memory at electrode scale, where the interlayer structure converges towards a reproducible state. Our findings reveal cycling-induced structural memory that governs subsequent intercalation in layered MXenes.
Comments36 pages, 5 figures
