Reconfiguring Self-Assembly of Photoresponsive Hybrid Colloids
Ning Kang1, Jiao Zhu1, Xiaoliang Zhang1, Huaguang Wang1,*（王华光）, and Zexin Zhang1,2,*（张泽新）
1 College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
2 College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China; Institute for Advanced Study, Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
J. Am. Chem. Soc.2022, 144, 4754--4758
The reconfigurable self-assembly of colloidal particles allows the bottom-up creation of adaptive materials, yet significant challenges remain. Here, we demonstrate a synthesis of photoresponsive Fe2O3/polysiloxane hybrid colloids that perform a dynamically reconfigurable self-assembly. Such self-assembly is due to chemical gradients originating from the decomposition of H2O2 by the Fe2O3 component under UV irradiation. The morphology of the self-assembly includes chains and flower-structures, where the chains can be transformed in situ into flower-like structures with decreasing UV intensity. The flower-structures can be further switched by applying an external magnetic field, leading to orientationally ordered clusters. This, interestingly, leads to an asymmetrical chemical gradient surrounding the assemblies, and transforms the cluster into a micromotor exhibiting a self-propulsion steerable by the magnetic field. Our findings demonstrate a new possibility to control and reconfigure the self-assembly of colloids, which offers an important pathway for fabrications of adaptive and smart materials at the microscale.
链接：//pubs.acs.org/doi/abs/10.1021/jacs.2c00432
