Broadband Short-Range Surface Plasmon Structures for Absorption Enhancement in Organic Photovoltaics

Electrical and Computer Engineering Department, Lehigh University, Bethlehem, PA 18015, USA.
Optics Express (Impact Factor: 3.49). 11/2010; 18 Suppl 4(23):A620-30. DOI: 10.1364/OE.18.00A620
Source: PubMed

ABSTRACT

We theoretically demonstrate a polarization-independent nanopatterned ultra-thin metallic structure supporting short-range surface plasmon polariton (SRSPP) modes to improve the performance of organic solar cells. The physical mechanism and the mode distribution of the SRSPP excited in the cell device were analyzed, and reveal that the SRSPP-assisted broadband absorption enhancement peak could be tuned by tailoring the parameters of the nanopatterned metallic structure. Three-dimensional finite-difference time domain calculations show that this plasmonic structure can enhance the optical absorption of polymer-based photovoltaics by 39% to 112%, depending on the nature of the active layer (corresponding to an enhancement in short-circuit current density by 47% to 130%). These results are promising for the design of organic photovoltaics with enhanced performance.

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Available from: Zakya H. Kafafi, Apr 04, 2015
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    • "For textured substrates, which often demanded invert structures instead of using traditional ITO glasses, also led to over filling of the valleys and shunts at the crests of the device structures [15]. Moreover, extensive studies of light-trapping have been focused either on silicon solar cells rather than PSCs [16] [17], or on the simulation and characterization of optical properties rather than the consideration of the optical and electrical performances experimentally [18]. Even the few experimental works reported for trapping light in thin-film PSCs, enhanced absorption did not lead to a homologous relationship with the improved photocurrent and enhanced PCE [19] [20]. "
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