Structural and optical properties of brominated Cu thin films

Abstract

We describe and discuss XRD, FESEM-EDS and optical absorption behavior of nanostructured 50 nm Cu thin films obtained by thermal evaporation and subsequently exposed to bromine vapours. XRD patterns show quasi-amorphous structure due to the nanocrystalline nature of cupper particles. As bromination time increases there is a subtle broadening of the peak that hints at a possible increase in quantities such as particle size. At ambient temperature, bromination time could be used to tune surface morphology, and optical properties of nanostructured Cu thin films. During the short term bromination we observed small Cu Nanoparticles with large density, which exhibit surface plasmon resonance (SPR). Increase of bromination time yields larger Cu Nanoparticles with small density of particles, the particle size and elemental composition assessed by FESEM-EDS. These results offer a promising strategy for situ characterization and monitoring of nanopaticl and for the engineering of Cu nanoparticle with new plasmonic properties even as Cu and brominated Cu films could be promising candidates for plasmonic and nanophotonic applications.