離子選擇性傳輸對於細胞的功能和分析設備至關重要（例如:離子選擇性電極和離子梯度電池）。受細胞離子通道啟發，具有官能基化孔洞的多孔材料被廣泛應用於離子分離與傳輸的薄膜設計中，例如:金屬有機框架材料(MOFs)、共價有機框架材料(COFs)以及中孔二氧化矽。這些材料可以通過以下特性實現離子選擇性：(1)孔徑控制：亞奈米級孔徑的孔洞可有助於去除水合殼層，實現高度選擇性；而奈米級孔徑的孔洞則依靠靜電吸引離子，並有助於保留離子的水合殼層，從而實現更快的傳輸。(2)可進行配位鍵結的官能基：具有官能基的孔洞可以通過配位鍵結的方式吸附特定離子，從而實現選擇性離子傳輸。然而，儘管亞奈米孔洞能夠提供高選擇性，但因水合作用受限，通常會導致離子傳輸速率降低。因此，在選擇性與傳輸速率之間取得平衡，是實現高效離子傳輸的關鍵。在本研究中，我們採用中孔二氧化矽 SBA-15（孔徑為 6-8 nm）為材料，研究離子在受限孔徑中的分配與傳輸行為，並通過電化學分析與定量分析進行實驗。與擁有亞奈米孔洞（<1 nm）的金屬有機框架材料和共價有機框架材料相比，SBA-15 不僅具有更穩定的結構，還兼具成本低廉與合成簡單的優勢。SBA-15 具有奈米級孔洞有助於具水合殼層的離子進行傳輸並維持選擇性，同時其帶負電荷的表面可與目標陽離子相互作用。本研究為快速且高選擇性的離子傳輸系統提供了一種具潛力的解決方案，並為未來的離子選擇性薄膜的開發提供了新的方向。

Ion-selective transport is crucial for cellular functions and analytical devices, such as ion-selective electrodes and ion-gradient cells. Inspired by cellular ion channels, porous membranes with functionalized pores like metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), and mesoporous silica are widely explored for ion separation and transport. These materials achieve ion selectivity through: (1) Pore size control: Sub-nanometer pores remove hydration shells for high selectivity, while nanometer pores rely on electrostatic attraction to retain water molecules for faster transport. (2) Functional group coordination: Functionalized pores adsorb ions based on affinity, enabling targeted transport. While sub-nanometer pores offer high selectivity, they often reduce ion conductivity due to limited hydration. Balancing selectivity and conductivity is key for efficient ion transport.
Here, we use mesoporous silica SBA-15 (pore size: 6-8 nm) to investigate ion partitioning and transport within confined pores, characterized by electrochemical and quantitative analysis. Compared to MOFs and COFs, which have sub-nanometer pores (<1 nm), SBA-15 offers a more chemical inert, lower cost, and easier synthesis. Its nanometer-sized pores support hydrated ion transport and maintain selectivity, while its negatively charged surface interacts with targeted cations. This research provides a promising avenue for developing fast, selective ion transport systems.

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