Oriented carbon nanotube arrays (OCNTAs) are a unique microstructure consisting of carbon nanotubes (CNTs) oriented along their longitudinal axes normal to a substrate surface. These OCNTAs effectively preserve and often accentuate the unique anisotropic properties of individual carbon nanotubes, which possess a morphology that may be precisely controlled. https://www.alfa-chemistry.com/products/oriented-carbon-nanotube-array-49.htm