Electron-transport and gas sensing in armchair graphene nanoribbons by density functional method

Abstract

Findings regarding the application of gas sensing on graphene based material have led to jump in nanotechnology. Hence, producing the high-efficiency materials in this technology is a priority. Recent development in graphene based material shows that it can be a good candidate for this tar-get. With this in mind, we theoretically studied the effect of different gas molecule absorption on armchair graphene nanoribbon. In order to identify, the electronic transport of armchair graphene nanoribbons AGNR (8) by using non-equilibrium Green’s function technique, the TRANSIESTA package was used. In order to study the geometry relaxation of device, Spanish Initiative for Electronic Simulations with Thousands of Atoms (SIESTA) package was applied. Also, the generalized gradient approximation of Perdew, Burke and Ernzerhof (PBE) were chosen for the exchange correlation density function. For studying the gas sensing properties of AGNR numerical computations for CO, NO, CO2, and NH3gas molecules were adsorbed on the AGNR (8). Besides, the average local density of states (LDOS) and the transmission spectra T (E, V) for gas molecules adsorbed on the AGNR (8) were plotted. The current was measured as a function of the voltage of applied bias and the transmission spectra was investigated to see the effects of all configurations in the presence of gas molecules. Our results are encouraging and leading experimental research to develop high-quality graphene materials for well-organized applications base on gas sensing.