Interaction of Au Atom on Single Walled Carbon Nanotube: A Density Functional Study

Abstract

The interaction of Au atom on Single Walled Carbon Nanotube (8, 0) (SWCNT) has been studied using first principal of Density Functional Theory (DFT). In this study we found structural change in surface geometry of SWCNT and electronic variation in its semiconducting nature. To interpret these properties, we performed geometry optimization of pristine SWCNT and Au- SWCNT system for four different sites. Then we performed calculation for band structure (BS), density of state (DOS) and Mulliken population analysis with DMol3 code. Au atom is found chemisorbed on SWCNT on atomic site by binding distance 2.7 Å where it is physisorbed for all other sites by binding distance 2.99 Å at axial, 2.96-3.102 Å at chiral and 3.663-3.520 Å at hexagon respectively. The bond angles between C - C - C bonds were ranging from116⁰ to 119.5⁰ which is less than 120⁰ indicates trigonal structure of bonding and prefers sp2 hybridization . Thus the properties of SWCNT can be modified by the adsorbed Au adatom by minute variation in semiconducting nature and surface geometry.