Atomic insights into the interaction of N2, CO2, NH3, NO, and NO2 gas molecules with Zn2(V, Nb, Ta)N3 ternary nitride monolayers

Abstract

The search for promising carrier blocking layer materials with high stability, including resistance to surface inhibition by environmental molecules that cause a drop in carrier mobility, is critical for the production of tandem solar cells. Based on density functional theory calculations, the reaction of atmospheric gases, including N₂, CO₂, NH₃, NO, and NO₂, with three promising Zn₂(V, Nb, Ta)N₃ monolayers is discovered. The results suggest the chemical adsorption of NH₃ and physical adsorption of NO and NO₂. In addition, the Zn₂(V, Nb, Ta)N₃ monolayers are characterized by a weak bonding with N₂ and CO₂. Charge redistribution is found at the interface between the monolayers and NH₃, NO and NO₂ molecules, leading to the formation of a local surface dipole that affects the functionality of the Zn₂(V, Nb, Ta)N₃ monolayers. The Zn₂VN₃ monolayer is less reactive with atmospheric gases and thus is the most promising for application in tandem solar cells. Notably, the revealed nontrivial behavior of the Zn₂(V, Nb, Ta)N₃ monolayers towards N-containing gases makes them promising for application in gas sensing. Specifically, the Zn₂TaN₃ monolayer is the most promising for application in molecular sensing due to its high reversibility and distinguished interaction with NH₃, NO, and NO₂ gases.