Open AccessGeometric light trapping with a V-trap for efficient organic solar cells
Author(s) -
Soo Jin Kim,
George Y. Margulis,
Seung Rim,
Mark L. Brongersma,
Michael D. McGehee,
Peter Peumans
Publication year - 2013
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.21.00a305
Subject(s) - quantum efficiency , optoelectronics , materials science , polymer solar cell , trapping , organic solar cell , energy conversion efficiency , active layer , absorption (acoustics) , optics , sunlight , solar cell , plasmonic solar cell , theory of solar cells , solar cell efficiency , layer (electronics) , polymer , nanotechnology , physics , ecology , thin film transistor , composite material , biology
The efficiency of today's most efficient organic solar cells is primarily limited by the ability of the active layer to absorb all the sunlight. While internal quantum efficiencies exceeding 90% are common, the external quantum efficiency rarely exceeds 70%. Light trapping techniques that increase the ability of a given active layer to absorb light are common in inorganic solar cells but have only been applied to organic solar cells with limited success. Here, we analyze the light trapping mechanism for a cell with a V-shape substrate configuration and demonstrate significantly improved photon absorption in an 5.3%-efficient PCDTBT:PC(70)BM bulk heterojunction polymer solar cell. The measured short circuit current density improves by 29%, in agreement with model predictions, and the power conversion efficiency increases to 7.2%, a 35% improvement over the performance in the absence of a light trap.