One such route may be themal plasma functionalization of CNT. The advantage of this method is that it minimizes the defects in the nanotube

...which is of course extremely important. The more control - the better!

could you kindly elucidate the method a bit further??

The C-atoms of CNT are excited at elevated temperatures and ionised gas is made to react with it in the reaction chamber.

Which type of ionised gas do you have experience with?

Ammonia

Did u use ammonia for functionalisation?? -NH3 functionalisation i presume?

right