Ab Initio Modeling of Doped/Undoped ArGNR Sensors for No2 Detection

Abstract

Elevated levels of nitrogen dioxide (NO ₂ ) pollutants have captured significant attention due to their profound influence on the cardiovascular and respiratory systems; hence, high-performance monitoring systems for pollutants are imperative to safeguard the well-being of individuals. In this regard, a hydrogen-passivated two-probe Armchair Graphene Nanoribbon (ArGNR) gas sensor utilizing a doped/undoped configuration can be considered to mitigate the NO ₂ pollutants. Therefore, this research, for the first time, examines the influence of channel length and transport properties on the i-v behavior of NO ₂ pollutants for doped/undoped ArGNR-based sensors. The electronic properties are rigorously examined using the density function theory (DFT) within the linear combination of atomic orbital (LCAO) and semi-empirical computation techniques, leveraging principles derived from non-equilibrium Green's function. In comparison to the undoped ArGNR, the BAs doped ArGNR exhibits superior chemisorption energy of −2.3 eV (with spin effect) and −3.3 eV (without spin effect), coupled with the substantial bandgap variation of −10.22, 36.50% (with spin effect) and 100% (without spin effect), at the B and As sites, respectively. In addition, a high quantum transport spectrum of 57% and significant current variations of 95% and 77% at the B and As sites, respectively, upon the NO ₂ adsorption. These findings suggest that the B-As-doped ArGNR sensor provides a promising solution for susceptible NO ₂ detection.