Spark plasma sintering of double-walled carbon nanotubes

Bulk samples of double-walled carbon nanotubes are prepared for the first time. The best spark plasma sintering conditions are (1100 degrees C, 100 MPa). Raman spectroscopy and scanning electron microscopy show that the nanotubes are undamaged. The density is equal to 1.29 g cm(-3) and the pores are all below 6 nm in diameter. The electrical conductivity is equal to 1650 S cm(-1). The transverse fracture strength is equal to 47 MPa. (c) 2008 Elsevier Ltd. All rights reserved.