Construction Of High-efficiency Self-drive Motor Based On Long-range Interaction Mechanism

Self-propelled nano/micromotors are nano/micro devices that can convert other forms of energy into mechanical energy for their autonomous motion.The micro-scale cargo transport are carried out through the interaction between the nano/micromotors and the passive‘cargo’,which in turn offers the motors great potentials in drug delivery,environmental detection and remediation,etc.However,as a nano/micro device that are designed to perform special tasks,their efficiency of finishing tasks（consisted of energy transmission and conversion efficiency）is a key factor for the numerous applications.At the present,the energy transmission efficiency（the ratio of the mechanical energy of the motor to the external input energy）and energy conversion efficiency（the ratio of the energy required for the cargo to overcome the viscous resistance and the mechanical energy consumed by the motor movement）are extremely low.To solve the above mentioned problems,we developed a Janus self-driven motor with highly efficient treatment of oil contamination by constructing the long-range interaction between a hydrophobic motor and oil droplets.We further discoverd a self-propelled mixed colloidal system induced by coupling opposite electroosmotic flow from divese microparticles and progrssed an efficient mixed micromotors system.Firstly,we proposed and fabricated a self-propelled Janus foam motor for on-the-fly oil absorption on water surface.Using this long-range capillary interaction between the motor and the oil droplets,the high energy transfer efficiency of the motor was achieved,and their efficiency in the treatment of oil pollution was explored application.The self-propelled Janus foam motor is fabricated by simply loading camphor/stearic acid（SA）mixture as fuels into one end of the SA-modified polyvinyl alcohol（PVA）foam.The as-proposed Janus foam motors show an efficient Marangoni effect-based self-propulsion on water surace with a long lifetime due to the controlled slowly release of camphor by the hydrophobic SA in the fuel mixture.By using the capillary interaction between the motors and oil droplets,the interacted distance between the motor and the oil droplets is up to 9 mm and lead to a high energy transfer efficiency.Furthermore,the foam motors can automatically search,capture,and absorb oil droplets on-the-fly,and then spontaneously self-assemble after oil absorption due to their self-propulsion as well as the attractive capillary interactions between the motors and oil droplets.Since the as-developed Janus foam motors can effectively integrate intriguing behaviors of the self-propulsion,efficient oil capture,and spontaneous self-assembly,they hold great promise for practical applications in water treatment.Secondly,the binary cooperative complementary phenomenon,which means everything contain two entirely opposite but cooperative complementary statuses and evolve due to the dynamic development of the two statuses,is a basic discipline of nature and can be observed and applied in numerous field.Inspired by this phenomenon,we designed a novel self-propelled mechanism for micromotors by coupling interpaticles a long-range repulsion-attraction interaction due to the opposite of diffusioosmotic flow from colloidal particles.Through this method,two kinds of microparticles are capable of cooperative autonomous moving when they initially performed Brownian motion in water respectively.Compared to the traditional catalytic self-propelled micromotor,the micromotors in mixed colloidal system has a higher power conversion efficiency due to the lack of some ways to loss energy which caused from the side reaction of catalytic reaction.This mixed slef-propped mechanism was applied to mixed particles sytems which were made up wtih CdS and TiO₂ particles,Ag₃PO₄ and TiO₂ particles,AgBr and ZnO particles.Furthermore,The collective and chemotactic behaviors of micromotors are showed in mixed colloidal system due to the dynamic interparticles repulsion-attraction interaction.We believe this work could inspire a noval effective way to study and design biomimetic intelligent inorganic system.