Combinatorial method to prepare metal nanoparticles that catalyze the growth of single-walled carbon nanotubes

Enhanced surface diffusion at the growth temperature of single-walled carbon nanotubes (SWNTs) can cause coarsening of metal catalysts. By balancing the nominal thickness and surface diffusion length of metals, metal nanoparticles of desirable size are expected to form spontaneously under the SWNTs growth conditions. Our combinatorial method, using a library of nominally 0.001 to 1 nm thick sputter-deposited cobalt patterns, identified in a single experimental run that cobalt nanoparticles from submonolayers can catalyze the growth of high-quality SWNTs.