LAUSR

Conversion of the metallic SWCNT to semiconducting SWCNT was achieved by band structure engineering of the nanotube by functionalization of the DNA nucleobase, guanine. The band structure analysis revealed that metallic SWCNT (6, 0), when surface engineered with guanine nucleobase with H-atom attachment as the functional group, is converted to a semiconductor one by opening a narrow bandgap with a value of 0.08 eV. This phenomenon was brought about by strong chemisorption due to hydrogenation by inducing partial sp3 hybridization in the nanotube structure. No bandgap openings were observed when guanine was adsorbed on the pristine nanotube surface by its nitrogen site and oxygen site respectively. Related zero-bias transmission spectra and IV-curve supported the result also. The entire study was done at room temperature using ATK-VNL simulation software.