In this report, we have demonstrated the photoluminescence quenching and energy transfer properties of semiconducting polymer nanoparticles, poly (N-vinylcarbazole) (PVK) in presence of different sized Au nanoparticles by steady state and time-resolved spectroscopy. We have described the quenching phenomena by sphere of action static quenching mechanism and both dynamic and static quenching processes are found in these systems. PL quenching values are 24.22% and 57.3% for 14 nm and 18 nm Au nanoparticles, respectively. It is found that the radiative and nonradiative decay have been modified with the size of Au nanoparticles. PL quenching and shortening of decay time regarding polymer nanoparticles in presence of Au nanoparticles suggest the nonradiative energy transfer process. The values of energy transfer are 6.7%, 49.5% and 53.38% from PVK polymer nanoparticles to 3 nm, 14 nm and 18 nm Au nanoparticles, respectively. Using FRET and SET equations we have calculated the average distance of donor PVK polymer nanoparticles and acceptor Au nanoparticles.

Design of highly luminescent nanomaterials is an emerging area of research for photonic and bio-photonic applications. Nowadays, dye-encapsulated polymer nanoparticles (PNPs) are found to be very promising alternative nextgenerationluminescent nanomaterials because of extraordinary brightness, easy synthesis, higher photo-stability and nontoxic behaviour. Herein, we have highlighted the dynamics of the fluorophore molecules inside PNPs. Furthermore, we discuss the fundamental correlation of particle brightness with the size of the PNPs as well as population of the dye molecules inside the PNPs. Considering the resonance energy transfer process, generation of white light by varying the dye concentration and singlet oxygen generation using photosensitizer dye have been described. Finally, we discuss the importance of hybrids of conjugated PNPs for potential light harvesting systems such as photovoltaic and optoelectronic applications.