The use of a perylenediimide derivative as a dopant in hole transport layer of an organic light emitting device

► A PDI derivative, was used as a dopant in the hole transport layer of green OLED. ► PDI doping increased the luminous and power efficiencies by a factor of 15. ► PDI acts as a trap for holes leading to a better charge balance. ► Surface roughness is an important parameter on OLED performance. ► PDI presence reduced the surface roughness from 1.5 nm to 0.75-0.85 nm.