Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Plasmonic nanograting design for inverted polymer solar cells

Open Access Open Access

Abstract

Plasmonic nanostructures for effective light trapping in a variety of photovoltaics have been actively studied. Metallic nanograting structures are one of promising architectures. In this study, we investigated numerically absorption enhancement mechanisms in inverted polymer photovoltaics with one dimensional Ag nanograting in backcontact. An optical spacer layer of TiO2, which also may act as an electron transport layer, was introduced between nanograting pillars. Using a finite-difference-time domain method and performing a modal analysis, we explored correlations between absorption enhancements and dimensional parameters of nanograting such as period as well as height and width. The optimal design of nanograting for effective light trapping especially near optical band gap of an active layer was discussed, and 23% of absorption enhancement in a random polarization was demonstrated numerically with the optimally designed nanograting. In addition, the beneficial role of the optical spacer in plasmonic light trapping was also discussed.

©2012 Optical Society of America

Full Article  |  PDF Article
More Like This
Plasmonic backcontact grating for P3HT:PCBM organic solar cells enabling strong optical absorption increased in all polarizations

Mustafa Akin Sefunc, Ali Kemal Okyay, and Hilmi Volkan Demir
Opt. Express 19(15) 14200-14209 (2011)

Optical design of transparent metal grids for plasmonic absorption enhancement in ultrathin organic solar cells

Inho Kim, Taek Seong Lee, Doo Seok Jeong, Wook Seong Lee, Won Mok Kim, and Kyeong-Seok Lee
Opt. Express 21(S4) A669-A676 (2013)

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (9)

Fig. 1
Fig. 1 A three dimensional schematic and a cross-sectional image of the inverted polymer solar cell.
Fig. 2
Fig. 2 (a) Number of absorbed photons in the active layers with varying TiO2 thickness. Open square denotes the case without an spacer layer. (b) The absorption enhancements of the cells with varying TiO2 thickness. Absorption enhancement is the normalized number of absorbed photons in the cell with TiO2 with reference to the cell without TiO2.
Fig. 3
Fig. 3 (a) Dispersion curves of the TE0, the TM0 and the SPP modes for device structures Ag/P3HT:PCBM 150 nm/PEDOT:PSS 50 nm (black symbol), and Ag/TiO2 50 nm/P3HT:PCBM 150 nm/PEDOT:PSS 50 nm (red symbol) as a function of a propagation wave vector(kx). The solid lines are the dispersion curves of the SPP modes for the semi-infinite bilayers (blue line: Ag/P3HT:PCBM, red line: Ag/TiO2), and the red dashed line is the vacuum light line. (b) Dispersion curves as a function of the nanograting period with the same legend as Fig. 3(a). (c) Normalized optical field intensity profiles of the TE0, the TM0, and the SPP modes for the case without TiO2 at the wavelength of 650 nm. (d) Normalized optical field intensity profiles of the TE0, the TM0, and the SPP modes for the case with TiO2 at the wavelength of 650 nm.
Fig. 4
Fig. 4 (a) Absorption spectra of the active layers in a TE polarization of incident light as a function of the period for the cell with nanograting of a 50 nm height and a 150 nm width. The white dashed and the dash-dotted lines denote the simulated dispersion curves for the cells with and without TiO2, respectively. (b) The normalized E-field intensity distributions at position 1 (nanograting period: 400nm, wavelength: 650 nm). (c) The normalized E-field intensity distributions at position 2 (nanograting period: 400 nm, wavelength: 678 nm).
Fig. 5
Fig. 5 (a) Absorption spectra of the active layers in a TM polarization of incident light as a function of period for the cell with nanograting of a 50 nm height and a 150 nm width. The white dashed and the dash-dotted lines denote the simulated dispersion curves of the SPP and the TM0 modes for the cells without and with TiO2, respectively. (b) The normalized H-field intensity distributions at position 1 (nanograting period: 350nm, wavelength: 701 nm). (c) The normalized H-field intensity distributions at position 2 (nanograting period: 500 nm, wavelength: 664 nm). (d) The normalized H-field intensity distributions at position 3 (nanograting period: 350 nm, wavelength: 636 nm).
Fig. 6
Fig. 6 The number of absorbed photons as a function of nanograting period for the cell with a 50 nm height and a 150 nm width in TE, TM, and random polarizations.
Fig. 7
Fig. 7 (a) absorption enhancements with varying a height and a width of nanograting in (a) TE, (b) TM and (c) random polarizations for the cells with a nanograting period of 380 nm.
Fig. 8
Fig. 8 Absorption spectra of 100 nm thick active layers as a function of the nanograting period in (a) TE and (b) TM polarizations. Absorption spectra of 75 nm thick active layers as a function of the nanograting period in (c) TE and (d) TM polarizations. The dashed and dash-dotted lines are the dispersion curves of the TE0 modes for the case with and without TiO2 in (a), (c). The dashed line is the dispersion curve of the SPP mode for the case without TiO2 in (b), (d).
Fig. 9
Fig. 9 (a) Absorption spectra of 150 nm thick active layers for the case without nanograting and the case with nanograting in TE and TM polarizations. (b) The number of absorbed photons in TE, TM, and random polarizations, and absorption enhancements as a function of an active layer thickness. The red dashed line denotes 20% of the absorption enhancement.

Equations (3)

Equations on this page are rendered with MathJax. Learn more.

P=ω× ε × V | E | 2 dV
k x = 2π λ ( ε m ε d ε m + ε d )
k x =n 2π p
Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved