Analysis and optimization of surface plasmon-enhanced organic solar cells with a metallic crossed grating electrode

Optics Express (Impact Factor: 3.53). 09/2012; 20 Suppl 5(19):A740-53. DOI: 10.1364/OE.20.00A740
Source: PubMed

ABSTRACT We perform a systematic analysis of enhanced short-circuit current density (Jsc) in organic solar cells (OSCs) where one metallic electrode is optically thick and the other consists of a two-dimensional metallic crossed grating. By examining a model device representative of such surface plasmon (SP)-enhanced OSCs by the Fourier modal and finite-element methods for electromagnetic and exciton diffusion calculations, respectively, we provide general guidelines to maximize Jsc of the SP-enhanced OSCs. Based on this study, we optimize the performance of a small-molecule OSC employing a copper phthalocyanine-fullerene donor-acceptor pair, demonstrating that the optimized SP-enhanced device has Jsc that is 75 % larger than that of the optimized device with an ITO-based conventional structure.

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