Interchain photoluminescence in substituted polyfluorenes

• We have characterised the interchain emitting states of two substituted polyfluorenes with steady-state and time-resolved photoluminescence (PL). Site selective excitation of the interchain state shows that physical dimers are formed in the film. These dimers have low concentration in the films but exciton diffusion to the dimers is reducing the intrachain exciton lifetime. With asymmetrical substituents, the PL quantum yield is higher and the PL lifetime is longer due to lower concentration of dimers. Slow cooling from the melt, gives a new red shifted emission band and less intrachain emission. A discrepancy in the calculated radiative lifetimes suggest a fast formation of this new band.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Nyckelord

Photoluminescence

Polyfluorenes and derivatives

Time-resolved fast spectroscopy

UV-Vis-Nir absorption

TECHNOLOGY

TEKNIKVETENSKAP

photoluminescence

uv-vis-nir absorption

polyfluorenes and derivatives

time-resolved fast spectroscopy

Publikations- och innehållstyp

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