Institut de Chimie de Lyon, UMR 5265 CNRS-Université de Lyon 1-ESCPE Lyon, C2P2, Equipe Chimie Organométallique de Surface, ESCPE 43 Boulevard du 11 Novembre 1918, F-69616 Villeurbanne, France.
Phys Chem Chem Phys. 2011 Aug 14;13(30):13527-36. doi: 10.1039/c1cp20623k. Epub 2011 May 20.
Ionic liquids are a stabilizing medium for the in situ synthesis of ruthenium nanoparticles. Herein we show that the addition of molecular polar solutes to the ionic liquid, even in low concentrations, eliminates the role of the ionic liquid 3D structure in controlling the size of ruthenium nanoparticles, and can induce their aggregation. We have performed the synthesis of ruthenium nanoparticles by decomposition of [Ru(COD)(COT)] in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C(1)C(4)Im][NTf(2)], under H(2) in the presence of varying amounts of water or 1-octylamine. For water added during the synthesis of metallic nanoparticles, a decrease of the solubility in the ionic liquid was observed, showed by nanoparticles located at the interface between aqueous and ionic phases. When 1-octylamine is present during the synthesis, stable nanoparticles of a constant size are obtained. When 1-octylamine is added after the synthesis, aggregation of the ruthenium nanoparticles is observed. In order to explain these phenomena, we have explored the molecular interactions between the different species using (13)C-NMR and DOSY (Diffusional Order Spectroscopy) experiments, mixing calorimetry, surface tension measurements and molecular simulations. We conclude that the behaviour of the ruthenium nanoparticles in [C(1)C(4)Im][NTf(2)] in the presence of 1-octylamine depends on the interaction between the ligand and the nanoparticles in terms of the energetics but also of the structural arrangement of the amine at the nanoparticle's surface.
离子液体是原位合成钌纳米粒子的稳定介质。本文表明，即使在低浓度下，向离子液体中添加分子极性溶质也会消除离子液体 3D 结构对控制钌纳米粒子尺寸的作用，并可能诱导其聚集。我们已经在 H 2 存在下，通过 [Ru(COD)(COT)] 在 1-丁基-3-甲基咪唑双（三氟甲基磺酰基）亚胺，[C(1)C(4)Im][NTf(2)] 中的分解，来合成钌纳米粒子，同时加入不同量的水或 1-辛胺。对于在合成金属纳米粒子过程中加入的水，观察到其在离子液体中的溶解度降低，这是通过位于水相和离子相之间的纳米粒子表现出来的。当在合成过程中存在 1-辛胺时，会得到尺寸稳定的纳米粒子。当在合成后加入 1-辛胺时，会观察到钌纳米粒子的聚集。为了解释这些现象，我们使用 (13)C-NMR 和 DOSY（扩散有序光谱）实验、混合量热法、表面张力测量和分子模拟，探索了不同物种之间的分子相互作用。我们得出结论，在 1-辛胺存在下，[C(1)C(4)Im][NTf(2)] 中钌纳米粒子的行为取决于配体与纳米粒子之间的相互作用，无论是从能量角度还是从胺在纳米粒子表面的结构排列角度来看都是如此。
