In a mixture of tetraphenylporphyrin (TPP) and fullerene (C60) doped in a PMMA film, fluorescence of TPP is enhanced and de-enhanced by an electric field in zinc and free-base compounds, respectively, indicating that the electron transfer from the excited state of TPP to C60 is decelerated in zinc compounds and accelerated in free-base compounds by an electric field. TPP was found to form complex upon mixing with C60 which exhibits a broad emission in the wavelength region longer than that of the TPP emission. The complex emission is significantly quenched by an external electric field in both zinc and free base compounds, suggesting that the nonradiative decay of the excited complex is accelerated by an electric field in both cases.
- Electric field effects
- Photoinduced electron transfer