Piezoelectric Effects on the Exciton Dissociation Rate in Organic-Inorganic Hybrid Systems

Abstract

In this study, we perform a numerical investigation on the piezoelectric effects on the exciton dissociation (i.e., Onsager dissociation rate) on the interface in an organic (P3HT)-inorganic (n-ZnO) hybrid system using a Finite Element Method (FEM). The results show that the maximum dissociation rate on the interface is determined by the positive piezoelectric potential, which is associated with the piezoelectric effects that assist exciton dissociation by the collection of free carriers inside the hybrid system. We numerically prove this effect by calculating the piezoelectric charge, the number of holes, and the electron density on the interface under elongated hybrid systems. The results obtained are expected to give a better understanding of piezoelectric effects on the exciton dissociation and net carrier density.

Keywords:

• Onsager dissociation rate
• piezoelectric effect
• excitons
• p-n junction