Effectiveness of p -dopants in an organic hole transporting material

We investigated the effectiveness of p -dopants to generate holes in a hole transporting material by comparing the absorption in visible-near-infrared and infrared regions and current density-voltage characteristics. CuI, MoO 3 , and ReO 3 having different work functions were doped in a hole transporting organic material, 4 , 4 ′ , 4 ″ -tris(N-(2-naphthyl)-N-phenylamino)-triphenylamine (2TNATA). Formation of charge transfer (CT) complexes increases linearly with increasing doping concentration for all the dopants. Dopants with higher work function ( ReO 3 > MoO 3 > CuI ) are more effective in the formation of CT complexes and in the generation of the charges in the doped films.