Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569 Stuttgart, Germany.
Department of Physics, Indian Institute of Science Education and Research Bhopal, India.
Chem Commun (Camb). 2018 Oct 28;54(84):11933-11936. doi: 10.1039/c8cc06467a. Epub 2018 Oct 4.
Self-propelling chemical motors have thus far required the fabrication of Janus particles with an asymmetric catalyst distribution. Here, we demonstrate that simple, isotropic colloids can spontaneously assemble to yield dimer motors that self-propel. In a mixture of isotropic titanium dioxide colloids with photo-chemical catalytic activity and passive silica colloids, light illumination causes diffusiophoretic attractions between the active and passive particles and leads to the formation of dimers. The dimers constitute a symmetry-broken motor, whose dynamics can be fully controlled by the illumination conditions. Computer simulations reproduce the dynamics of the colloids and are in good agreement with experiments. The current work presents a simple route to obtain large numbers of self-propelling chemical motors from a dispersion of spherically symmetric colloids through spontaneous symmetry breaking.
自推进化学马达迄今为止需要制造具有不对称催化剂分布的詹尼斯粒子。在这里，我们证明了简单的各向同性胶体可以自发组装，产生自推进的二聚体马达。在具有光化学催化活性和被动二氧化硅胶体的各向同性二氧化钛胶体混合物中，光照射导致活性和被动颗粒之间的扩散吸引，并导致二聚体的形成。二聚体构成了一个对称破缺的马达，其动力学可以通过照射条件完全控制。计算机模拟再现了胶体的动力学，与实验结果吻合良好。目前的工作提供了一种简单的途径，通过自发对称破缺，从球形对称胶体的分散体中获得大量自推进化学马达。
