The role of charge-matching in nanoporous materials formation
The role of charge-matching in nanoporous materials formation
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DOI：
10.1039/c8mh01640b
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发表时间：
2019-06-01
影响因子：
13.3
通讯作者：
Jorge, Miguel
中科院分区：
文献类型：
--
作者：
Centi, Alessia;Manning, Joseph R. H.;Jorge, Miguel
揭示导致介观有序多孔材料形成的分子水平机制是实现计算材料设计目标的关键一步。对于以烷基胺表面活性剂为模板的二氧化硅，基于溶液中中性胺和中性硅酸盐之间氢键相互作用的机理已被材料科学界广泛接受，尽管缺乏确凿的证据支持它。所谓的“中性模板路线”并不代表六方介孔二氧化硅（HMS）的合成机理的可行描述，HMS是胺模板多孔二氧化硅的最早实例。相反，材料的介观结构由胺和硅酸盐之间的离子相互作用的电荷匹配来定义。这对合成各种模板化多孔材料具有深远的意义，并可能为开发高价值多孔材料的可持续和经济路线提供新的思路。
Unravelling themolecular-level mechanisms that lead to the formation of mesoscale-ordered porous materials is a crucial step towards the goal of computational material design. For silica templated by alkylamine surfactants, amechanism based on hydrogen-bond interactions between neutral amines and neutral silicates in solution has been widely accepted by the materials science community, despite the lack of conclusive evidence to support it. We demonstrate, through a combination of experimental measurements and multiscale modelling, that the so-called "neutral templating route" does not represent a viable description of the synthesis mechanism of hexagonal mesoporous silica (HMS), the earliest example of amine-templated porous silica. Instead, the mesoscale structure of the material is defined by charge-matching of ionic interactions between amines and silicates. This has profound implications for the synthesis of a wide range of templated porous materials, and may shed new light on developing sustainable and economical routes to high value porous materials.