Device model for operation of polymer/fullerene bulk heterojunction solar cells

Abstract

Abstract:

We have developed a numerical device model that consistently describes the current-voltage characteristics of polymer:fullerene bulk heterojunction solar cells. Bimolecular recombination and a temperature and fielddependent generation mechanism of free charges are incorporated. It is demonstrated that in poly based solar cells space-charge effects only play a minor role, leading to a relatively constant electric field in the device. Furthermore, at short-circuit conditions only 7% of all free carriers are lost due to bimolecular recombination. The model predicts that an increased hole mobility together with a reduction of the acceptor strength of 0.5 eV will lead to a maximum attainable efficiency of 5.5% in the PPV/PCBM-based solar cells.

Key words: Polymer solar cells, bulk heterojunction, numerical simulation, free charges;mobility

CLC Number:

O441.4

XIAO Feng, YUAN Shi-Tao, HUANG Zhi-Xiang, WU Xian-Liang. Device model for operation of polymer/fullerene bulk heterojunction solar cells[J]. J4, 2015, 32(3): 371-377.

References

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