Stimulus-Responsive Planet−Satellite Nanostructures as Colloidal Actuators: Reversible Contraction and Expansion of the Planet− Satellite Distance

Structural plasticity and its control at thenanoscale are a vivid area of material science. In thiscontribution, we report a conceptually simple and versatilestrategy for the formation of reconfigurable nanoparticlearrangements. The key role in our approach is played by starblock copolymers from controlled radical RAFT polymerization,which fulfill the dual task of guiding the particlearrangement and also of equipping the nanomaterials withstimulus-responsiveness. By virtue of their block structure, thestar polymers provide at the same time colloidal stability andresponsive properties. Structural switching in response to the applied stimulus was investigated by means of small-angle X-rayscattering and dynamic light scattering. The developed approach is general, easy to implement, and may provide new prospectsfor the development of colloidal actuators, nanoscale materials with switchable properties, and nanoscale machines.