Electron Injection and Transport Properties of Phenazine Compounds with Fused Rings

Electron injection and the transport properties of three phenazine compounds, tetrabenzophenazine (TBP), dibenzodipyridophenazine (DBDPP), and tetrapyridophenazine (TPP), were investigated to determine the effect of nitrogen atoms in fused-ring molecules. These three compounds worked as electron transport materials, exhibiting high electron mobility – on the order of 10-3 cm2 V-1 s-1. Increasing the number of nitrogen atoms deepened the energy levels and lowered crystallinity in vacuum-deposited films. In particular, TPP containing six nitrogen atoms showed very efficient electron injection from an aluminum cathode.