Abstract: Methods for growing carbon nanotubes on single crystal substrates are disclosed. A method of producing a nanostructure material comprises coating a single crystal substrate with a catalyst film to form a catalyst coated substrate; annealing the catalyst film by supplying a first promoter gas to the catalyst coated substrate at a first temperature and a first pressure; and supplying a second promoter gas and a carbon-source gas to the catalyst coated substrate in a substantially water-free atmosphere at a second pressure and a second temperature for a time period to cause growth of nanostructures on the catalyst coated substrate. The nanostructure material is used in various applications.