Zhang Jiali, Piunova Victoria A, Liu Yang, Tek Andy, Yang Qingbo, Frommer Jane, Liu Gang-Yu, Sly Joseph
Department of Chemistry , University of California , Davis , California 95616 , United States.
IBM Almaden Research Center , 650 Harry Road , San Jose , California 95120 , United States.
J Phys Chem Lett. 2018 Nov 1;9(21):6232-6237. doi: 10.1021/acs.jpclett.8b02442. Epub 2018 Oct 18.
Assembly from ultrasmall solution droplets follows a different dynamic from that of larger scales. Using an independently controlled microfluidic probe in an atomic force microscope, subfemtoliter aqueous droplets containing polymers produce well-defined features with dimensions as small as tens of nanometers. The initial shape of the droplet and the concentration of solute within the droplet play significant roles in the final assembly of polymers due to the ultrafast evaporation rate and spatial confinement by the small droplets. These effects are used to control the final molecular assembly in terms of feature geometry and distribution and packing of individual molecules within the features. This work introduces new means of control over molecular assembly, bringing us closer to programmable synthesis for chemistry and materials science. The outcomes pave the way for three-dimensional (3D) nanoprinting in additive manufacturing.
超小溶液微滴的组装遵循与较大尺度不同的动力学。在原子力显微镜中使用独立控制的微流体探针，含有聚合物的亚飞升级水滴会产生尺寸小至几十纳米的明确定义的特征。由于超快的蒸发速率和小液滴的空间限制，液滴的初始形状和液滴内溶质的浓度在聚合物的最终组装中起着重要作用。这些效应被用于根据特征几何形状、特征内单个分子的分布和堆积来控制最终的分子组装。这项工作引入了控制分子组装的新方法，使我们更接近化学和材料科学的可编程合成。这些成果为增材制造中的三维（3D）纳米打印铺平了道路。
