Feedback Controlled Colloidal Self-Assembly
Feedback Controlled Colloidal Self-Assembly
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DOI：
10.1002/adfm.201200400
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发表时间：
2012-09-25
影响因子：
19
通讯作者：
Bevan, Michael A.
中科院分区：
文献类型：
--
作者：
Juarez, Jaime J.;Bevan, Michael A.
胶体自组装为制备具有新性质的空间周期性超材料提供了一条很有前途的途径，对许多新兴技术具有重要意义。然而，胶体组装通常是通过不可逆的阶跃变化启动的，并沿着未指明的、非平衡的动力学路径进行，几乎没有机会操纵缺陷或重新配置微观结构。在这里，我们展示了一种概念上的新方法，它能够使用反馈控制来定量和可逆地指导无序流体和晶体构型之间胶体系综的动态演化。这种方法的关键是使用自由能景观模型来告知反馈控制律，从而闭合实时感知(通过序参数)和驱动(通过可调电势)之间的回路。这种方法展示了受控组装以创造有序材料并进行主动重新配置，其基础是化学物理，这表明它可以推广到其他微观过程。
Colloidal self-assembly provides one promising route to fabricate spatially periodic meta-materials with novel properties important to a number of emerging technologies. However, colloidal assembly is generally initiated via irreversible step-changes and proceeds along unspecified, non-equilibrium kinetic pathways with little opportunity to manipulate defects or reconfigure microstructures. Here, a conceptually new approach that enables the use of feedback control to quantitatively and reversibly guide the dynamic evolution of colloid ensembles between disordered fluid and crystalline configurations is demonstrated. The key to this approach is the use of free energy landscape models to inform feedback control laws that close the loop between real-time sensing (via order parameters) and actuation (via tunable electrical potentials). This approach, which demonstrates controlled assembly to create ordered materials and perform active reconfiguration, is based on chemical physics that suggest it can be generalized to other microscopic processes.