Open AccessHomo-tandem structures to achieve the ideal external quantum efficiency in small molecular organic solar cells
Author(s) -
Sang Hoon Lee,
JungYong Lee
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.00a697
Subject(s) - tandem , quantum efficiency , energy conversion efficiency , materials science , optoelectronics , absorption (acoustics) , organic solar cell , optics , physics , polymer , composite material
In this study, we report a homo-tandem structure of small molecular organic solar cells (SMOSCs) using identical single-junction devices as sub-cells. The trade-off between the absorption and internal quantum efficiency (IQE) of single-junction devices tends to limit the external quantum efficiency (EQE). However, multiple-stacked thin cells with maximized IQE in homo-tandem structures amplify the absorption to achieve the ideal EQE. As a result, a high power conversion efficiency of 7.81% is achieved in tetraphenyldibenzoperiflanthene (DBP):C 70 -based homo-tandem SMOSCs, which is 21.8% higher than that in a single-junction device.