Experimental and computational investigations of structural and photoluminescence properties of PVK/SWCNTs nanocomposites

A simple mechanical dispersion method was used to elaborate new nanocomposite from the combination of single walled carbon nanotubes (SWCNTs) and polyvinylcarbazole (PVK) polymer. The obtained samples were annealed at the moderate temperature of 333 K to achieve good dispersion and inhibit phase separation. Force constants calculations using Density Functional theory were correlated with FTIR measurements to support the interaction between both components. Raman scattering was used to check the dispersion state of SWCNTs on the PVK polymer. Optical absorption analysis and stationary photoluminescence and time resolved photoluminescence technics have been used to elucidate the change of optical properties after SWCNTs adding. The formation of bulk nano-hetero-junction resulting from the extended interfaces, leading to efficient dissociation of the charge pairs was shown by quenching effects in polymer photoluminescence when increasing SWCNTS contents. A noticeable decrease of the life time is observed by time resolved photoluminescence, which reflects the shortness of diffusion pathways and consequently an improvement of the electron transfer.