University of Sussex , Falmer, Brighton BN1 9RH, United Kingdom.
Langmuir. 2017 Dec 26;33(51):14766-14771. doi: 10.1021/acs.langmuir.7b03867. Epub 2017 Dec 13.
To prepare high-quality Langmuir films of 2D materials it is important to select a solvent optimized for both exfoliation and spreading at the air-water interface. Whereas it is generally accepted that exfoliation and stabilization of 2D materials is well-described using the Hansen solubility parameter theory, a complementary description of solvent spreading behavior is lacking. To this end we develop an understanding of solvent spreading using a Hansen solubility parameter framework. Our model accurately predicts the behavior of both water-immiscible and water-miscible solvents in Langmuir film formation experiments. We demonstrate that spreading behavior can be modified by controlling the surface pressure of the subphase using an amphiphilic species and accordingly utilize this approach to determine the maximum spreading pressure for a selection of solvents. Ultimately, by building on this understanding we open up additional routes to optimize the preparation of Langmuir films of 2D materials and other nanoparticles.
为了制备高质量的二维材料 Langmuir 膜，选择一种既能实现剥离又能在气液界面上实现铺展的溶剂非常重要。虽然人们普遍认为，用 Hansen 溶解度参数理论可以很好地描述二维材料的剥离和稳定，但对于溶剂铺展行为的补充描述却缺乏。为此，我们使用 Hansen 溶解度参数框架来理解溶剂铺展。我们的模型准确地预测了 Langmuir 成膜实验中既不混溶又混溶的溶剂的行为。我们证明，通过使用两亲性物质控制亚相的表面压力，可以改变铺展行为，因此，我们利用这种方法确定了一系列溶剂的最大铺展压力。最终，通过建立在这一理解基础上，我们开辟了优化二维材料和其他纳米粒子 Langmuir 膜制备的新途径。
