Fabrication Of Self-propelled Tubular Micro/nanomotors And Their Driven Mechanism

Synthetic micro/nanomotors are new devices for energy conversion, which can convert chemical energy, solar energy and other different energy into mechanical energy. Multi-functionalized micro/nanomotors draw the inspiration from nature and life, which applies to human health and other area in turn. However, the application of most synthetic micro/nanomotors limits to the high cost and low biocompatibility. Here we demonstrated tubular motors with great value and prospects, because they have internal and external surfaces that can be functionalized modified with multi-functional materials. Layer by layer technology and the surface sol-gel method were prepared in different shapes and sizes of tubular micro/nanomotors. According to the characteristics of the tubular motors, different ways of actuation were employed. Here we research three systems that micro silica torpedoes driven by near-infrared light, asymmetry silica tubular motors driven by ultrasonic, and polyelectrolyte tubular motors driven by E.coli.We demonstrate a gold cluster partcial functionalized silica torpedo with the aid of near-infrared light-driven propulsion in diverse aqueous media. The local thermal gradient from the gold cluster upon NIR-irradiation through photothermal effect, provides a thermophoretic force along the asymmetric silica torpedo for directional propulsion and controllable explosion. The clean harmless near-infrared light drive the microscale torpedo moving in straight line with uniform velocity. And asymmetric deposition of gold nanoparticles make controllable velocity and explosion.In order to explore a different way of actuation, anodized aluminum template and polycarbonate template were employed to fabricate dumbbell-shaped nanotubes and tubular motors by using SSG method. The motor can be driven to produce linear motion, arc motion, rotation, movement, aggregation, rotating with linear motion and other motion modes by ultrasonic. The movemental model depending on the shape and surrounding of the motors.After giving up a large complex of exogenous driving force, E. coli was employed to a simple and effective driving source. We develop E.coli with high activity by exploring the culture time. Comparing different hydrophilic or hydrophobic materials, and attractor or inhibitor of bacterial, we find that hydrophilicity is a necessary condition for the attachment of E.coli. Also the appearance of inhibitor will hinder E. coli attaching the synthetic motors.