Coupled opto-electronic simulation of organic bulk-heterojunction solar cells: parameter extraction and sensitivity analysis

TL;DR

This paper presents a coupled opto-electronic simulation method for organic bulk-heterojunction solar cells, focusing on parameter extraction and sensitivity analysis to improve understanding of device behavior.

Contribution

It introduces a comprehensive simulation approach that extracts key parameters and analyzes their influence, addressing discrepancies between models and experiments.

Findings

Identified parameter sets fitting experimental data

Discovered discrepancies in thickness dependence of I-V curves

Suggested measurement of turn-off photocurrent for mobility estimation

Abstract

A general problem arising in computer simulations is the number of material and device parameters, which have to be determined by dedicated experiments and simulation-based parameter extraction. In this study we analyze measurements of the short-circuit current dependence on the active layer thickness and current-voltage curves in poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) based solar cells. We have identified a set of parameter values including dissociation parameters that describe the experimental data. The overall agreement of our model with experiment is good, however a discrepancy in the thickness dependence of the current-voltage curve questions the influence of the electric field in the dissociation process. In addition transient simulations are analyzed which show that a measurement of the turn-off photocurrent can be useful for estimating charge carrier mobilities.