Photoluminescence from Silver/carbon nanotubes composite

In this work we present a study of growth and characterization of silver/carbon nanotube (CNT) composites. The composites were prepared with chemical mix techniques and characterized with SEM analysis, X-ray Photoelectron Spectroscopy (XPS) and Photoluminescence (PL) Spectroscopy. The analysis showed that the sample is formed by an uniform network of silver microparticles in direct contact between CNT. SEM images show CNTs overlapping Ag micrometer particles while XPS spectroscopy indicates the presence of chemical bonds between Ag and CNT. Photoluminescence spectra, taken from samples at room temperature, show a yellow–red luminescence signal with two bands centered at about 530 and 670 nm. Moreover, measurements of optical absorbance indicate great difference between the spectra of pure CNT and composites. As well known, pure CNTs have a NIR absorption band at about 1.3 eV, our Ag/CNT composites, instead, show three bands: one in the UV (0.2 eV), one in visible region (1.5–2.9 eV) and a NIR band at about 1.3 eV. These optical results indicate changes in band structures of the Ag/CNT composites compared to pure CNT and Ag particles and open the possibility to use these new materials in optoelectronic devices.