Synthesis of SnO2 functionalized amorphous carbon nanotube for efficient electron field emission application

Amorphous carbon nanotubes (aCNTs) were synthesized by a very simple low-temperature solid state reaction. The walls of the as prepared aCNTs were decorated with chemically synthesized SnO2 nanoparticle both by in situ and ex situ process. All the samples were characterized by X-ray diffraction, field emission scanning electron microscope, high resolution transmission electron microscope, X-ray photoelectron spectroscopy. It is observed that when functionalization of SnO2 particles onto aCNTs wall was performed by in situ process it results a uniform coating, whereas ex situ treatment gives discrete attachment of SnO2 onto aCNTs wall. The field emission properties of as synthesized and modified sample were carried out in the laboratory made high vacuum field emission set up. Result of field emission has been compared with pure aCNTs and pure SnO2. It has been found that attachment of SnO2 nanostructure can effectively enhance the field electron emission of the aCNTs with lowering the turn on field from 6.57 to 2.15 V/mu m. The enhancement of field emission characteristic is believed to be due to the enhanced roughness of the coated aCNTs wall as well as lower work function of outer SnO2 material. (c) 2013 Published by Elsevier B.V.