Confinement Effects in Dynamics of Ionic Liquids with Polymer‐Grafted Nanoparticles
Confinement Effects in Dynamics of Ionic Liquids with Polymer‐Grafted Nanoparticles
复制标题
聚合物接枝纳米颗粒离子液体动力学的限制效应
DOI：
10.1002/cphc.202200219
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发表时间：
2022
期刊：
影响因子：
2.9
通讯作者：
Akcora, Pinar
中科院分区：
文献类型：
--
作者：
Liu, Siqi;Li, Ruhao;Tyagi, Madhusudan;Akcora, Pinar
在我们以前的研究中，发现离子液体与聚甲基丙烯酸甲酯接枝的Fe 3 O 4纳米颗粒聚集体在低颗粒浓度下混合时表现出与纯离子液体不同的动力学和离子电导率。在这项工作中，我们报告的准弹性中子散射结果的离子液体含有聚合物接枝的Fe 3 O 4纳米粒子在较高的粒子浓度。通过限制作用讨论了聚甲基丙烯酸甲酯接枝Fe 3 O 4纳米粒子存在下1-己基-3-甲基咪唑双（三氟甲基磺酰基）酰亚胺（HMIM-TFSI）中咪唑（HMIM+）阳离子的扩散系数.对弹性非相干结构因子的分析表明，在HMIM-TFSI/溶剂混合物中加入接枝颗粒，限制半径减小。我们提出，由高浓度的接枝颗粒引起的限制缩小了HMIM-TFSI受限体积。我们进一步推测，这种增强的扩散率发生作为聚（甲基丙烯酸甲酯）接枝的Fe 3 O 4纳米粒子的聚集体内的阳离子的局部排序的结果。
Ionic liquid mixed with poly(methyl methacrylate)‐grafted Fe3O4nanoparticle aggregates at low particle concentrations was found to exhibit different dynamics and ionic conductivity than that of pure ionic liquid in our previous studies. In this work, we report on the quasi‐elastic neutron scattering results of ionic liquid containing polymer‐grafted Fe3O4nanoparticles at higher particle concentrations. The diffusivity of imidazolium (HMIM+) cations of 1‐hexyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (HMIM‐TFSI) in the presence of poly(methyl methacrylate)‐grafted Fe3O4nanoparticles is discussed through the confinement. Analysis of the elastic incoherent structure factor revealed that the confinement radius decreased with the addition of grafted particles in HMIM‐TFSI/solvent mixture. We propose the confinement that is induced by the high concentration of grafted particles shrinks the HMIM‐TFSI restricted volume. We further conjecture that this enhanced diffusivity occurs as a result of the local ordering of cations within aggregates of poly(methyl methacrylate)‐grafted Fe3O4nanoparticles.