It is well known that silicon solar cell resulted in the achievement of the major 25 % efficiency milestone [1] by passivated emitter, rear locally diffused cell, very close to the theoretical maximum efficiency for a single junction cell with Eg=1.1 eV of 31 % [2]. New initiatives to harvest incident photons with greater efficiency could therefore be considered to improve the energy conversion features of silicon based devices, which actually cover almost 95% of the photovoltaic market, as monocrystalline, multicrystalline, amorphous based material. As reported in literature [3,4], an increase of the energy conversion efficiency of commercially available silicon solar cells could be obtained exploiting the solar spectrum component below 450 nm, this high energy tail being not efficiently converted from silicon. Molecular systems strongly absorbing in this spectral range and showing a consistent Stokes shift of their emission towards the region of the maximum conversion efficiency of the photovoltaic device are good candidates for down-shifting of the absorbed light. Rare earth organic complexes constituted by a conjugated molecule acting as antenna (or sensitizer) and by an emitting lanthanide ion present the separation between the absorption and the emission bands required to obtain large Stokes shift and to avoid self-absorption losses. The design of efficient organolanthanide down-shifters suitable for different PV applications (namely terrestrial or space ones) is possible by a proper choice of the organic antenna. As well, different rare earth emitting ion can be considered to fit the optical features of the solar cell converter. In this work the characteristics of such “luminescent down –shifting” layer and their applicability on standard silicon solar cells are reviewed and discussed . In particular, in this work the optical and electrical characterization of commercial c-Si solar cells coated with layers doped with different Eu3+ organic complexes is presented. Such Eu3+-doped layers are able to realize down-shifting of photons with wavelength lower than 400 nm without introducing strong modifications of the industrial process leading to the fabrication of the PV modules. An increase of 2.8% of the total delivered power has been observed by encapsulating solar cells with Eu3+-doped PVA [5]. Other host matrixes compatible with PV module fabrication have been also tested. A further enhancement of the cell conversion efficiency is obtained exploiting a wider portion of the solar spectrum, using a Eu3+ organic complexes whose absorption is shifted towards the visible through the presence of a co-ligand . References [1] M. Green Prog. Photovolt: Res. Appl. 2009; 17 (2009) 320 [2] W. Schockley, H.J. Queisser J. Appl. Phys. 32 (1961) 510 [3] C. Strümpel, M. McCann, G. Beaucarne, V. Arkhipov, A. Slaoui, V. Svrcek, C. del Canizo, I. Tobias, Solar Energy Materials & Solar Cells 91 (2007) 238 [4] B.S. Richards, Solar Energy Materials & Solar Cells 90 (2006) 1189 [5] A. Le Donne, M. Acciarri, D. Narducci, S. Marchionna, S. Binetti, Prog. Photovolt: Res. Appl. 17(8) (2009) 519

Binetti, S. (2011). Increasing the efficiency of Si-based solar cell using rare earth organic complexes as down-shifters. In Proceedings of China Semiconductor Technology International Conference (CSTIC) SEMI- CHINA 2011 (pp.201-201).

Increasing the efficiency of Si-based solar cell using rare earth organic complexes as down-shifters

BINETTI, SIMONA OLGA
Primo
2011

Abstract

It is well known that silicon solar cell resulted in the achievement of the major 25 % efficiency milestone [1] by passivated emitter, rear locally diffused cell, very close to the theoretical maximum efficiency for a single junction cell with Eg=1.1 eV of 31 % [2]. New initiatives to harvest incident photons with greater efficiency could therefore be considered to improve the energy conversion features of silicon based devices, which actually cover almost 95% of the photovoltaic market, as monocrystalline, multicrystalline, amorphous based material. As reported in literature [3,4], an increase of the energy conversion efficiency of commercially available silicon solar cells could be obtained exploiting the solar spectrum component below 450 nm, this high energy tail being not efficiently converted from silicon. Molecular systems strongly absorbing in this spectral range and showing a consistent Stokes shift of their emission towards the region of the maximum conversion efficiency of the photovoltaic device are good candidates for down-shifting of the absorbed light. Rare earth organic complexes constituted by a conjugated molecule acting as antenna (or sensitizer) and by an emitting lanthanide ion present the separation between the absorption and the emission bands required to obtain large Stokes shift and to avoid self-absorption losses. The design of efficient organolanthanide down-shifters suitable for different PV applications (namely terrestrial or space ones) is possible by a proper choice of the organic antenna. As well, different rare earth emitting ion can be considered to fit the optical features of the solar cell converter. In this work the characteristics of such “luminescent down –shifting” layer and their applicability on standard silicon solar cells are reviewed and discussed . In particular, in this work the optical and electrical characterization of commercial c-Si solar cells coated with layers doped with different Eu3+ organic complexes is presented. Such Eu3+-doped layers are able to realize down-shifting of photons with wavelength lower than 400 nm without introducing strong modifications of the industrial process leading to the fabrication of the PV modules. An increase of 2.8% of the total delivered power has been observed by encapsulating solar cells with Eu3+-doped PVA [5]. Other host matrixes compatible with PV module fabrication have been also tested. A further enhancement of the cell conversion efficiency is obtained exploiting a wider portion of the solar spectrum, using a Eu3+ organic complexes whose absorption is shifted towards the visible through the presence of a co-ligand . References [1] M. Green Prog. Photovolt: Res. Appl. 2009; 17 (2009) 320 [2] W. Schockley, H.J. Queisser J. Appl. Phys. 32 (1961) 510 [3] C. Strümpel, M. McCann, G. Beaucarne, V. Arkhipov, A. Slaoui, V. Svrcek, C. del Canizo, I. Tobias, Solar Energy Materials & Solar Cells 91 (2007) 238 [4] B.S. Richards, Solar Energy Materials & Solar Cells 90 (2006) 1189 [5] A. Le Donne, M. Acciarri, D. Narducci, S. Marchionna, S. Binetti, Prog. Photovolt: Res. Appl. 17(8) (2009) 519
abstract + slide
Silicon , down shifter , solar cells, Europium
English
China Semiconductor Technology International Conference (CSTIC) SEMI- CHINA 2011
2011
Proceedings of China Semiconductor Technology International Conference (CSTIC) SEMI- CHINA 2011
2011
201
201
none
Binetti, S. (2011). Increasing the efficiency of Si-based solar cell using rare earth organic complexes as down-shifters. In Proceedings of China Semiconductor Technology International Conference (CSTIC) SEMI- CHINA 2011 (pp.201-201).
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/72356
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