Current density of anodes, recombination rate and luminance in MEH-PPV, MDMO-PPV, and P3HT polymers in polymer light-emitting diodes

Abstract

The present study examined polymer-based organic light-emitting diodes (PLEDs) with the different active layers using Silvaco Atlas software. The electrical and optical responses of the devices were evaluated through the characteristics of current-voltage, luminance, and recombination rate. The performance of the device strongly depends on the physical properties of the active layer. A better understanding of the effect of varying the parameters of the active layer, such as mobility, lifetime, and band gap, on the functioning of the device is necessary to achieve further improvement in these applications. This work presents a theoretical study of PLEDs having different active layers. Poly[2-methoxy-5-(3’,7’-dimethyloctyloxy)-1,4-phenylenevinylene], poly(3-hexylthiophene), and poly[2-methoxy-5-(2’-ethylhexyloxy)-p-phenylene vinylene] organic layers were deposited on an ITO substrate and the structure of the device was completed by a calcium cathode with a work function of 2.9 eV. The Langevin and Poole-Frenkel models were used to analyze the devices. The Langevin model was used to analyze the recombination rate and investigate the relationship between luminance, recombination rate, and the parameters of the active layer that have been less studied in previous works. Analysis of anode current density, luminance, and recombination rate indicate that poly(3-hexylthiophene) PLED shows better performance than others.