Modulating the Mechanical Properties of Supercrystalline Nanocomposite Materials via Solvent-Ligand Interactions
Modulating the Mechanical Properties of Supercrystalline Nanocomposite Materials via Solvent-Ligand Interactions
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DOI：
10.1021/acs.langmuir.9b01938
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发表时间：
2019-10-29
期刊：
影响因子：
3.9
通讯作者：
Schneider, Gerold A.
中科院分区：
文献类型：
--
作者：
Domenech, Berta;Plunkett, Alexander;Schneider, Gerold A.
超结晶纳米复合材料的微观力学性能接近珍珠层或类似的结构生物材料，可以通过有机改性的纳米粒子的自组装和进一步加强交联。这些纳米复合材料的强化是通过热处理来控制的，热处理促进纳米颗粒表面上叉指配体之间形成共价键。在这项工作中，它显示了如何的机械性能增强的程度可以控制的自组装步骤过程中使用的溶剂。我们发现，所得到的机械性能与用于超晶体组装的溶剂和配体的汉森溶解度参数相关：硬度和弹性模量随着溶剂的汉森溶解度参数接近稳定纳米颗粒的配体的汉森溶解度参数而降低。此外，它表明，自组装的超晶体，随后单轴压可以变形高达6%。这种变形的程度也与自组装步骤期间使用的溶剂密切相关。这些结果表明，纳米粒子表面的有机配体的构象和排列不仅控制自组装本身，而且影响所得超晶材料的机械性能。因此，汉森溶解度参数可以作为一种工具来预测应该使用什么溶剂和配体来获得具有良好机械性能的超晶体材料。
Supercrystalline nanocomposite materials with micro-mechanical properties approaching those of nacre or similar structural biomaterials can be produced by self-assembly of organically modified nanoparticles and further strengthened by cross-linking. The strengthening of these nanocomposites is controlled via thermal treatment, which promotes the formation of covalent bonds between interdigitated ligands on the nanoparticle surface. In this work, it is shown how the extent of the mechanical properties enhancement can be controlled by the solvent used during the self-assembly step. We find that the resulting mechanical properties correlate with the Hansen solubility parameters of the solvents and ligands used for the supercrystal assembly: the hardness and elastic modulus decrease as the Hansen solubility parameter of the solvent approaches the Hansen solubility parameter of the ligands that stabilize the nanoparticles. Moreover, it is shown that self-assembled supercrystals that are subsequently uniaxially pressed can deform up to 6 %. The extent of this deformation is also closely related to the solvent used during the self-assembly step. These results indicate that the conformation and arrangement of the organic ligands on the nanoparticle surface not only control the self-assembly itself but also influence the mechanical properties of the resulting supercrystalline material. The Hansen solubility parameters may therefore serve as a tool to predict what solvents and ligands should be used to obtain supercrystalline materials with good mechanical properties.