Invited feature articleCorrelation of nanodomain morphology and ultrafast fluorescence dynamics in bisdecylsexithiophene-polyethylene oxide copolymer film

- The aggregate nanodomains and intra-aggregate fluorescence dynamics are well correlate.
- Two-parameter cylindrical aggregate (200 × 400 nm) of the drop-cast film has two relaxation channels of 6.9 ps and 12.0 ps.
- One-parameter lamellar aggregate (1000 × 1000 nm) of the spin-coated film and one relaxation channel of 5.3 ps.

Bisdecylsexithiophene rods and polyethylene oxide coils forming alternating copolymer are of photo-physical interest. Nanodomain morphology by means of atomic force microscopy and steady-state/time-resolved fluorescence spectroscopy are correlated. Films, by using drop-casted and spin-coated preparation, consist of drops and terraces with average roughness Ra, maximal height Rmax, and nanodomain size to be 94.2 and 24.4 nm, 489.1 and 171.7 nm, and 200 × 400 nm and 1000 × 1000 nm, forming cylindrical and lamellar aggregates, respectively. The nanodomain aggregate thickness is 8 nm. The ultrafast dynamics of drop-casted and spin-coated films result in two relaxations of 6.9 ps and 12.0 ps, and only one relaxation of 5.3 ps, respectively. The simulation focuses on cylindrical (12 × 4 and (10 ± 2)x(4 ± 1)) and lamellar (12 × 12 and (10 ± 2)x(10 ± 2)) nanodomains. The aggregate nanodomains and intra-aggregate dynamics correlate as two-parameter drop-casted film and one-parameter spin-coated film.

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