Unraveling the injection barrier between electrode and organic layer in OLED device: A theoretical prediction model

[Display omitted] •A new model to predict the hole injection barrier involving the effect of ΦITO and the p-dopant concentration was developed based on the electronegativity equalized model.•The developed prediction model exhibits a remarkably accurate prediction of HIBs.•The developed prediction model for HIB will helps to find appropriate HTL/HIL organic materials without tremendous effort and time cost. This study developed a new prediction model for hole injection barriers. Based on the electronegativity equalized model (EEM), the vacuum level shift in the adjacent layers was further considered in this model. In addition, the variation in ΦITO, which is dependent on the doping concentration of Sn, was considered as one of the determinants for predicting the hole injection barrier (HIB) between ITO and the organic layer. Further, the effect of p-dopants on the HTL energy level was also introduced in this model. The predicted HIBs of various anode/organic junctions were quantitatively and qualitatively consistent with UPS experiments. We believe that the developed EEM model can aid in determining the appropriate HTL/HIL organic materials without tremendous effort and time costs.