Mechanical compliance of photolithographically defined vertically aligned carbon nanotube turf

We describe the micro-mechanical properties of vertically aligned carbon nanotubes (VACNTs) fabricated using a photolithographically patterned iron catalyst prepared using sol–gel techniques. The carbon nanotubes (CNTs) were grown via chemical vapor deposition. The relative mechanical stiffness of the resultant structure was measured using nanoindentation based techniques and is shown to be related to the number of contact sites between tubes. Elastic deformation occurs during compression at large strains, however energy is dissipated during deformation, likely through tube–tube interactions. The effective elastic modulii are depth dependent, due to the compression of pre-buckled geometries. The effective elastic modulii range between 0.03 and 0.08 GPa for a low number of contact sites and 0.1 and 0.3 GPa for a high number of contact sites.