Adsorption Analysis at Critical Temperature of PM2.5 Contaminants

Abstract

Increasing levels of PM2.5 (Particulate Matter having a diameter less than 2.5 µm) offer the highest risk, leading to a multitude of serious health complications, and hence the high-performance monitoring of these tiny pollutants may help to safeguard people's health. The sensitivity of PM2.5 pollutants to bulk gold as an application of sensors is investigated using the industry standard virtual nanolab. Within the framework of linear combination of atomic orbital (LCAO) computation, the density functional theory (DFT) is implemented using the Kohn–Sham formulation to analyze the electronic properties of bulk gold Au (111) substrate for specific PM2.5 pollutants (sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon dioxide (CO2), nitric oxide (NO), and carbon monoxide (CO)) sensing. The results demonstrate that different gases are adsorbed differently on Au (111), depending on their critical temperature (TC ). Consequently, NO is observed to be highly sensitive to Au (111) substrate due to its large band gap variation of −31% to −57%, considerable adsorption energy of −1.05 eV, and an improved charge transfer of 0.02 eV.