Phenanthro[9,10-d]imidazole as a new building block for blue light emitting materials

Abstract
The blue light emitting compound, BPPI, based on a phenanthro[9,10-d]imidazole group, is prepared by a facial synthetic process and exhibits excellent thermal stability, highly efficient fluorescence and balanced carrier injection. The double-layered device based on BPPI shows a higher maximum luminance and a lower turn-on voltage than the multi-layered one with an independent electron injection layer. The results suggest that the phenanthroimidazole unit is an excellent building block for tuning the carrier injection properties as well as blue emission.