The fabrication of integrated nanomachinary systems can enable break-through applications in nanoelectronics,
photonics, bioengineering, and drug delivery or disease treatment. Naturally occurring nanomotors are biological
motor proteins powered by catalytic reactions, which convert the chemical energy from the environment into
mechanical energy directly. It has been demonstrated recently that using a simple catalytic reaction and an
asymmetric bimetallic nanorod, one can produce catalytic nanomotors that mimic the autonomous motions of
bionanomotors. Yet the construction of artificial nanomachines remains a major contemporary challenge due to the
lack of a flexible fabrication technique that can design the desired dynamic components. We use a design technique
called dynamic shadowing growth that allows for the fabrication of a wide range of various geometries and the
asymmetric placement of the catalyst is easily accomplished as well which is necessary for directed propulsion.
Programming nanomotor behavior is possible through geometrically-focused design and by incorporating different
materials into the nanomotor structure is a simple process as well. A propulsion mechanism based upon bubble
ejection from the catalyst surface is introduced to explain the driving force, and the comparison of this driving
mechanism with the self-electrophoresis mechanism is also studied. We have also successfully incorporated multiple
parts to form complex nanomotor assemblies which exhibit motions not observed from individual parts by using magnetic interactions.
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