Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, UMR 7574, Chimie de la Matière Condensée de Paris, F-75005 Paris, France.
ACS Appl Mater Interfaces. 2014 Oct 8;6(19):17102-10. doi: 10.1021/am504770x. Epub 2014 Sep 13.
In this work, unique functional devices exhibiting controlled gradients of properties are fabricated by dip-coating process in acceleration mode. Through this new approach, thin films with "on-demand" thickness graded profiles at the submillimeter scale are prepared in an easy and versatile way, compatible for large-scale production. The technique is adapted to several relevant materials, including sol-gel dense and mesoporous metal oxides, block copolymers, metal-organic framework colloids, and commercial photoresists. In the first part of the Article, an investigation on the effect of the dip coating speed variation on the thickness profiles is reported together with the critical roles played by the evaporation rate and by the viscosity on the fluid draining-induced film formation. In the second part, dip-coating in acceleration mode is used to induce controlled variation of functionalities by playing on structural, chemical, or dimensional variations in nano- and microsystems. In order to demonstrate the full potentiality and versatility of the technique, original graded functional devices are made including optical interferometry mirrors with bidirectional gradients, one-dimensional photonic crystals with a stop-band gradient, graded microfluidic channels, and wetting gradient to induce droplet motion.
在这项工作中，通过加速模式的浸涂工艺制造了具有独特功能的梯度性能的器件。通过这种新方法，可以以简单且通用的方式在亚毫米范围内制备具有“按需”厚度梯度轮廓的薄膜，适用于大规模生产。该技术适用于多种相关材料，包括溶胶-凝胶致密和介孔金属氧化物、嵌段共聚物、金属有机骨架胶体和商业光致抗蚀剂。在文章的第一部分，报道了研究浸涂速度变化对厚度轮廓的影响，以及蒸发率和粘度对流体排出诱导成膜的关键作用。在第二部分，通过在纳米和微系统中进行结构、化学或尺寸变化，加速模式的浸涂用于诱导功能的可控变化。为了展示该技术的全部潜力和多功能性，制作了具有原始梯度功能的设备，包括具有双向梯度的光学干涉镜、具有带阻梯度的一维光子晶体、梯度微流道和润湿梯度以诱导液滴运动。
