▎ 摘　　要

Sensing properties of pristine armchair graphene nanoribbon (AGNR) and metal doped AGNRs (M-AGNRs; M=Al, Mn, Fe) are explored for selective detection of HF, HCl and HBr gases. Study of I-V characteristics reveal selective sensing capabilities of M-AGNRs. Origin of selectivity is explained based on differences in DOS profiles. Nonequilibrium Green's function formalism is used to set the chemiresistor device for analyzing the sensing ability of pristine and metal-doped (Al, Fe and Mn) armchair graphene nanoribbons (AGNRs) for the detection of hydrogen halide gases - HF, HCl and HBr. Metal doping is found to enhance the adsorptive strength and sensing ability of the ribbon. On Al-AGNR, all three halide gases follow dissociative chemisorption while on Fe-AGNR and Mn-AGNR, these gases adsorb nondissociatively. The computed current-voltage characteristics indicate selective response of Mn-AGNR toward HF and of Fe-AGNR toward HBr. The origin of this selectivity has been discussed in terms of difference in the density-of-state profiles of the studied AGNR systems.