Double Wall Carbon Nanotubes with an Inner Diameter of 0.4 nm

Abstract

Selective preparation of double wall carbon nanotubes (DWCNTs) is achieved by a floating iron catalyst CVD method with sufur promotion. SEM shows that the product consists of entangled nanotubes. HRTEM and Raman scattering have revealed that the smallest inner diameter of as‐grown carbon nanotubes is 0.4 nm (see Figure). The smallest diameter is found to be produced at the low carbon partial pressure with low sulfur content.