Chhatre Advait, Duttagupta Suvajeet, Thaokar Rochish, Mehra Anurag
Department of Chemical Engineering, Indian Institute of Techology - Bombay , Powai, Mumbai 400076, India.
Langmuir. 2015 Sep 29;31(38):10524-31. doi: 10.1021/acs.langmuir.5b02086. Epub 2015 Sep 16.
Hierarchical self-assembly is an elegant and energy-efficient bottom-up method for the structuring of complex materials. We demonstrate the synthesis of maghemite nanorods via directed self-assembly, assisted by wormlike micelles, under controlled shear. The experimental data are analyzed by formulating a "slithering snake" mechanism and simulating it on a cubic lattice, using a coarse-grained Monte Carlo framework. The influence of shear rate, precursor concentration, and length of Kuhn segment on the morphology of the nanorods is examined. Experiments indicate that the shear is necessary for the formation of nanorods, although diameter and length of the nanorods are insensitive to the shear rate, within the range of shear rates investigated. The model adequately captures the features of directional aggregation of particles, and the computed length and diameter correspond to the typical dimensions of the nanorods obtained experimentally. The protocol has considerable potential for producing nanorods of several materials simply by changing the precursors.
分级自组装是一种用于构建复杂材料的优雅且节能的自下而上的方法。我们展示了在可控剪切力作用下，通过蠕虫状胶束辅助的定向自组装合成磁赤铁矿纳米棒的过程。通过构建一种“滑行蛇”机制并在立方晶格上使用粗粒化蒙特卡罗框架对其进行模拟，来分析实验数据。研究了剪切速率、前驱体浓度和库恩链段长度对纳米棒形态的影响。实验表明，在所研究的剪切速率范围内，剪切力对于纳米棒的形成是必要的，尽管纳米棒的直径和长度对剪切速率不敏感。该模型充分捕捉了颗粒定向聚集的特征，计算得到的长度和直径与实验获得的纳米棒的典型尺寸相对应。该方案通过简单地改变前驱体，在生产多种材料的纳米棒方面具有相当大的潜力。
