Up-conversion photoluminescence in polyfluorene doped with metal (II)-octaethyl porphyrins

The up-conversion photoluminescence (PL) in films of polyfluorene (PF) doped with metallated porphyrins is reported for the first time. The dependence of the up-conversion process on the pump laser intensity and wavelength, the central metal moiety of the dopants, and the temperature is presented. Up-conversion emission is observed at pump intensities as low as 2 kW cm(-2). Comparison of the PF integral PL intensities after laser excitation by 532, 543, and 405 nm enables the discussion of the energy-transfer mechanism and the efficiency of the process.