Fig. 2.

(a) TEM images of pristine halloysite from Dragon Mine, Utah, Applied Minerals Inc. Scale bar is 1 μm. b) Zeta-potential alternation in the processes of LbL assembly of multilayer shells on halloysite clay nanotube (PAA – polyacrylic acid, PSS – polystyrene sulfonate, PEI – polyethyleneimine, PAH – polyallylamine hydrochloride; (c) TEM image of (PAH/PSS/(PAH/silica)2 tube coating.