Figure 2.
MWCNT-t: (a–d) intact nanotubes; (e–h) MWCNTs after several additions of NaOCllow; (i–l) MWCNTs after several additions of NaOClhigh; (a,e,i) general view; (b,f,j) the central area of MWCNTs, the inner channel and the walls are clearly seen; (c,g,k) tips of nanotubes, rounded cap is retained (pointed by arrows); and (d,h,l) electron diffraction patterns.