Metal-filled carbon nanotubes for nanomechatronics

Inter-nanotube mass transport along the central pores of carbon nanotubes (CNTs) is a fundamental problem for CNT-based nanofluidic devices. Besides the interest for testing classical theories of fluid flow at the nanoscale, CNT fluidic junctions are basic elements for more complex fluidic systems. Controlled melting, evaporation and flowing of copper and tin intra-/inter-nanotube shells are investigated experimentally. Cap-to-wall and wall-to-cap mass flow are realized by electric current driven heating, diffusion, and electromigration under low bias voltages between 1.5 V and 1.8 V. A comparison shows that the mass loss for the cap-to-wall architecture is much smaller than that for the wall-to-cap junction. Experimental investigation of electron-beam induced flowing of tin inside a kinked CNT shows the deformation of the junction, showing potential applications in actuations for nanofluidic relay, gripper fingers, or manipulator arms.