The conductance and mechanical properties of pure and contaminated silver nanowires were studied using density functional theory (DFT) calculations. Several nanowires containing O2 on their surface were elongated along two different directions. All of the NWs thinned down to single atom chains. In most simulations, the breaking force was not affected by the presence of the O2, and similar fracture strengths of ≈ 1 nN were computed for the pure and the impure NWs. When the O2 became incorporated in the single atom chain, the fracture occurred at the Ag-O bond and a lower fracture strength was found. All of the simulations show that the impurity interacted with the silver atoms to reduce the electron density in its nearby vicinity. A variety of conductance effects were observed depending on the location of the impurity. When the impurity migrates during the elongation to the thinnest part of the NW, it reduces the conductance significantly, and a ≈ 1 G0 conductance (usually associated with a single atom chain) was calculated for three- and two-dimensional structures. When the impurity was adjacent to the single atom chain, the conductance reduced almost to zero. However, when it stayed far from the thinnest part of the NW, the impurity had only a small influence on the conductance.
Citation: Journal of Physics Condensed Matter
Pub Type: Journals
Nanowire, Silver, Impurity, O2