Remote Magnetically Controlled Chemically Fueled Micromotor Disks

The design of functional nano/micro machines capable of carrying out complex tasks is an area of great current interest. Achieving this goal requires control of their motion trajectories on demand with precision. The addition of asymmetrically placed nickel stripes to chemically powered gold-platinum disks allows for precise control over particle motion through the application of magnetic fields. These electrophoretic particles are typically too large to move due to their aspect ratio and instead fall flat on one side. However, the particles can be oriented vertically using a magnetic field, allowing them to autonomously move through their environment. By utilizing multidirectional magnetic fields, we demonstrate how the motion of these particles can be initiated or stopped on demand and how their trajectories can be directed into specific patterns, such as orbital or rotational paths including sudden changes in direction or reciprocal motion. The particles can also pick up and move multiple cargo particles that are heavier than their weight.