Self-Dopant Formation in Poly(9,9-di-n-octylfluorene) Via a Dipping Method for Efficient and Stable Pure-Blue Electroluminescence


  • This work was financially supported by the Ministry of Education through project 91E-FA04-2-4A and by the National Science Council through NSC 95-2752-E-007-008-PAE. Supporting Information is available online from Wiley InterScience or from the author.


original image

Dipping pristine poly(9,9-di-n-octylfluorene) film into a mixed solvent/ nonsolvent THF/MeOH transforms the conformation of minor amorphous-phase chains to β-phase conformers (see figure) with a controllable content. The β phase acts as a dopant and causes electron trapping and promoted hole mobility. It allows efficient energy transfer and charge trapping and thus achieves pure-blue electroluminescence and enhanced device performance.