RESUMO
Despite their excellent electrical and optical properties, Ag nanowires (NWs) suffer from oxidation when exposed to air for several days. In this study, we synthesized a Cs carbonate-incorporated overcoating layer by spin-coating and ultraviolet curing to prevent the thermal oxidation of Ag NWs. Cs incorporation increased the decomposition temperature of the overcoating layer, thus enhancing its thermal resistance. The effects of the Cs carbonate-incorporated overcoating layer on the optoelectrical properties and stability of Ag NWs were investigated in detail. The Ag NW electrode reinforced with the Cs carbonate-incorporated overcoating layer exhibited excellent thermal oxidation stability after exposure to air for 55 days at 85 °C and a relative humidity of 85%. The novel overcoating layer synthesized in this study is a promising passivation layer for Ag NWs against thermal oxidation under ambient conditions. This overcoating layer can be applied in large-area optoelectronic devices based on Ag NW electrodes.
RESUMO
The local modification of intermolecular interactions in nickel-phthalocyanine molecules (NiPCs) is investigated on an Au(111) substrate using scanning tunneling microscopy. When the molecules are physisorbed on the substrate, they repel each other due to induced charge dipole moments. However, when the NiPC is chemisorbed on the substrate through the dehydrogenation of one of its ligands by a bias pulse, we find that a nearby physisorbed NiPC is attracted to the dehydrogenated ligand and trapped. Using our experimental results in combination with density functional theory calculations, we show that the observed attraction can be ascribed to the local charge redistribution around the dehydrogenated ligand of the chemisorbed NiPC. Furthermore, we demonstrate that desorption of the attracted NiPC from the trapped site can be readily controlled by changing the density of NiPCs around the dehydrogenated ligand.
