Carbon nanotube growth from metallic nanoparticles deposited by pulsed-laser deposition on different substrates

► The size of Fe or Ni nanoparticles depends on the combined effect between catalyst/substrate natures. ► A higher surface tension as for metal substrate, leads to nanoparticle formation with sizes larger than those obtained on insulating substrates. This is linked to the adhesion strength of catalyst particle on substrate. ► Tip growth (typically multi-walled nanotubes) is observed from catalyst nanoparticles on insulating substrates and base growth (bamboo-like nanotube) for conductor substrate.