Upconverter Silicon Solar Cell Devices for Efficient Utilization of Sub-Band-Gap Photons Under Concentrated Solar Radiation

作者：Fischer Stefan^*; Ivaturi Aruna; Froehlich Benjamin; Ruediger Marc; Richter Armin; Kraemer Karl W; Richards Bryce S; Goldschmidt Jan Christoph

来源：IEEE Journal of Photovoltaics, 2014, 4(1): 183-189.

DOI：10.1109/JPHOTOV.2013.2282744

• Optical frequency conversion
• photovoltaic cells
• silicon
• spectral conversion
• upconversion (UC)

Upconversion (UC) of sub-band-gap photons has the potential to increase the efficiency of solar cells significantly. We realized an upconverter solar cell device, by attaching an upconverter layer of beta-NaYF4 doped with 25% Er3+ embedded in the polymer perfluorocyclobutyl to the rear side of a bifacial silicon solar cell. We determined the external quantum efficiency of such upconverter solar cell devices under broad-band sub-band-gap excitation. Under consideration of spectral mismatch, we calculated the expected increase of the short-circuit current density due to UC under the air mass 1.5 global illumination. We determined an enhancement of 2.2 mA/cm(2) for a spectral excitation band ranging from 1450 to 1600 nm and a comparatively low solar concentration of 78 suns. Subsequently, a system of concentrator lens and upconverter solar cell device was characterized with a solar simulator. We determined an increase of the short-circuit current density due to UC of sub-band-gap photons of 13.1 mA/cm(2) under a concentration of 210 suns. This corresponds to a potential relative increase of the solar cell efficiency of 0.19%.

• 出版日期2014-1