Strategy toward Designing Semiconducting Polymer Nanoparticle Multichomophoric Dye Assembly

The design of semiconducting polymer nanoparticle based hybrids is promising for light harvesting systems. Here, we design a donor - acceptor system through tuning the energy level alignment of interacting counterparts for an efficient light harvesting system where poly(N-vinyl carbazole) (PVK) nanoparticles (NPs) act as donor and the newly designed bicolor fluorophore ([R6G][HFL]) acts as acceptor. The photophysical interaction between polymer nanoparticle and bicolor fluorophore has been investigated by spectroscopic study and density functional theory (DFT) calculations. Dynamic quenching and the shortening of decay time of PVK polymer nanoparticles are revealed due to the energy and electron transfer process from PVK nanoparticle to the surface attached bicolor fluorophore. Furthermore, an ultrafast spectroscopic study has been undertaken to investigate the decay dynamics of [R6G] [HFL] in the presence and absence of PVK. Finally, white light generation with CIE coordinates (0.31, 0.39) is achieved at a definite donor acceptor ratio (weight ratio of PVK:[R6G][HFL] = 5.39:1). Interesting findings reveal that polymer nanoparticle multichoromophoric dye assembly is promising for designing light harvesting systems.