Influence of surface oxidation on plasmon resonance in monolayer of gold and silver nanoparticles

Abstract

Surface plasmon resonance of gold and silver nanoparticle (NP) layers is investigated by the experiment as well as simulations. Although the good agreement was found for gold NP film, a significant mismatch in the resonance energy for silver NP film was observed. The deviation was assigned to the presence of silver oxide (Ag2O) in silver NPs. As an alternative to the NP size-dependent Drude model, the analysis based on effective medium approximation for refractive index of Ag-Ag2O material system is carried out and compared with the core-shell model. Both Mie's model and numerical simulation results illustrate shift of the surface plasmon resonance due to silver NP surface oxidation.

The role of the oxide shell in the chemical functionalization of plasmonic gallium nanoparticles

“…In addition, the intensity of the plasmon resonance is also affected by the oxide producing the attenuation of the signal due to the dielectric character of the oxide. However, this attenuation is not as intense as for Ag 22 and Al 23 . This is due to the lower extinction coefficient of Ga 2 O 3 compared to the other oxides 24 .…”

Structural, morphological and optical properties of Ag–AgO thin films with the effect of increasing film thickness and annealing temperature

“…Amongst, VDT is advantageous over wet chemistry routes because it can directly be used for the above mentioned applications before going for any surplus process. However, it oxidizes rapidly as soon as exposed to atmosphere [11,19,20]. It is a great challenge to deposit un-oxidized Ag NPs with the optimized size and shape which exhibits strong SPR near UV-Vis region.…”

“…The formation of AgO at the surface level due to air annealing process would not be really a big concern for SPR. However, it leads to a red shift due to an increase of dielectric constant of the medium in which NPs are present [12,20]. AgO is wide bad semiconducting material having potential applications such as optical memories [22], filters [23] and plasmon photonic devices [24].…”

How an oxide shell affects the ultraviolet plasmonic behavior of Ga, Mg, and Al nanostructures

“…However, the efficiencies of these metals depends sensitively on the surrounding dielectric environment, and all of them, except Au and Rh, form native oxides that wrap the NP with a shell, whose thickness depends on both the metal and the environmental exposure conditions (temperature and pressure). Consequently, it is essential to understand the effect of oxidation on their UV plasmonic response [7,9,19]. Also, very recently it was shown that, since oxidation is a means to grow a dielectric shell, its control may be used to tune the plasmonic resonance of NPs [14].…”