Influence of Temperature on Exciton Dynamic Processes in CuPc/C60 Based Solar Cells.

Lijia Chen,Qunliang Song,Pan Guo,Lianbin Niu,Lun Cai

doi:10.3390/mi12111295

Abstract

Although the effect of high temperature on the performance of organic solar cells has been widely investigated, it is inevitably influenced by the associated annealing effect (which usually leads to film morphology change and variation in electrical properties), which makes the discussion more sophisticated. In this study, we simplified the issue and investigated the influence of low temperatures (from room temperature to 77 K) on the photocurrent and internal/external quantum efficiency of a CuPc/C60 based solar cell. We found that besides the charge dynamic process (charge transport), one or more of the exciton dynamic processes, such as exciton diffusion and exciton dissociation, also play a significant role in affecting the photocurrent of organic solar cells at different temperatures. Additionally, the results showed that the temperature had negligible influence on the absorption of the CuPc film as well as the exciton generation process, but obviously influenced the other two exciton dynamic processes (exciton diffusion and exciton dissociation).

Highlights

The exciton and charge dynamic processes, including (i) exciton generation, (ii) exciton diffusion, (iii) exciton dissociation, (iv) free charge transportation and (v) charge collection are five important processes that determine the performance of organic solar cells (OSCs) and perovskite solar cells (PSCs) [1,2,3]
We found that the dependence of the exciton generation with temperature was different in CuPc thin film
CuPc thin film at low temperatures was investigated for the first time, which showed negligible device

Summary

Introduction

The exciton and charge dynamic processes, including (i) exciton generation, (ii) exciton diffusion, (iii) exciton dissociation, (iv) free charge transportation and (v) charge collection are five important processes that determine the performance of organic solar cells (OSCs) and perovskite solar cells (PSCs) [1,2,3]. The absorbance of the ITO/CuPc (20 nm)/C60 (55 nm)/Alq3 (6 nm)/Al) at room temperature using an UV-Vis at the peak absorption wavelengths, 620 nm and 700 nm, is about 1.6 times higher than spectrophotometer with a relative reflection measurement option.

Results

Conclusion