Recent advances of carbon nanotubes synthesis by the electric arc technique using atomized platinum-group metal catalysts

Abstract

The traditional application of platinum-group metals (PGMs: Ru, Rh, Pd, Os, Ir, Pt) as powder catalysts in the electric arc synthesis of carbon nanotubes (CNTs) is limited due to the inclusion of metal particles dispersed under electric arc conditions and the spoiling regularity of synthesized carbon nanotubes. In the current work, the authors applied the atomized platinum metal catalysts formed from the ionic compounds of PGMs under electric arc conditions, to avoid the occurrence of multiatomic metal particles in the CNT mass. Such an approach permits a synthesis of defectless CNTs, using PGMs as catalysts. All the six PGMs are good catalysts for CNT synthesis and CNTs do not form from graphite without a catalyst under electric arc conditions. The aim of this work is to comparatively characterize the six PGMs as atomized catalysts in the formation of carbon nanotubes, to enable a wider use of these highly catalytic metals.