Generation and agglomeration behaviour of size-selected sub-nm iron clusters as catalysts for the growth of carbon nanotubes

• Ravi Joshi,
• Benjamin Waldschmidt,
• Jörg Engstler,
• Rolf Schäfer and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2011, 2, 734–739, doi:10.3762/bjnano.2.80

• system with a base pressure in the range of 10−8 mbar is shown in Figure 5. Iron clusters were produced by a bimetallic cluster source (1) based on the laser vaporization technique: The fundamental-wavelength beam of a Nd:YAG laser (2a) with a pulse width of 8 ns and an intensity of typically 100 mJ

• /pulse was focused on an Fe rod (3), synchronized with a pulsed He flow (4) at a stagnation pressure of 6 bar and a duration of approximately 300 µs. Since only pure iron clusters were investigated in the present work the second Nd:YAG laser (2b) was switched off. The plasma generated by the laser pulse