Che Shengping, Zhang Jianhua, Mou Fangzhi, Guo Xia, Kauffman Joshua E, Sen Ayusman, Guan Jianguo
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, International School of Materials Science and Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China.
Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA.
Research (Wash D C). 2022 Jul 6;2022:9816562. doi: 10.34133/2022/9816562. eCollection 2022.
"Life-like" nonequilibrium assemblies are of increasing significance, but suffering from limited steerability as they are generally based on micro/nanomotors with inherent asymmetry in chemical composition or geometry, of which the vigorous random Brownian rotations disturb the local interactions. Here, we demonstrate that isotropic photocatalytic micromotors, due to the persistent phoretic flow from the illuminated to shadowed side irrespective of their Brownian rotations, experience light-programmable local interactions (reversibly from attraction to repulsion and/or alignment) depending on the direction of the incident lights. Thus, they can be organized into a variety of tunable nonequilibrium assemblies, such as apolar solids (i.e., immobile colloidal crystal), polar liquids (i.e., phototactic colloidal stream), and polar solids (i.e., phototactic colloidal crystal), which can further be "cut" into a predesigned pattern by utilizing the switching motor-motor interactions at superimposed-light edges. This work facilitates the development of active matters and motile functional microdevices.
“类生命”非平衡组装体的重要性日益凸显，但由于它们通常基于化学成分或几何结构具有固有不对称性的微/纳米马达，其剧烈的随机布朗旋转会干扰局部相互作用，导致可操控性有限。在此，我们证明，各向同性的光催化微马达，由于无论其布朗旋转如何，都会从光照面到阴影面产生持续的趋肤流，因此会根据入射光的方向经历光可编程的局部相互作用（从吸引到排斥和/或排列的可逆变化）。因此，它们可以被组织成各种可调谐的非平衡组装体，如非极性固体（即不动的胶体晶体）、极性液体（即光泳胶体流）和极性固体（即光泳胶体晶体），通过利用叠加光边缘处的马达 - 马达相互作用切换，这些组装体还可以进一步“切割”成预先设计的图案。这项工作推动了活性物质和能动功能微器件的发展。
