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DOE OSTI · 1885167

Bifacial CdTe Solar Cells with Copper Chromium Oxide Back-Buffer Layer

Pokhrel, Dipendra·Mathew, Xavier·Khanal Subedi, Kamala·Patel, Aesha·Phillips, Adam B.·Bastola, Ebin·Abudulimu, Abasi·Jamarkattel, Manoj K.·Rijal, Suman·Quader, Abdul·Friedl, Jared·Zawisza, Zachary·Yan, Yanfa·Heben, Michael J.·Ellingson, Randy J.
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Abstract

Bifacial solar cells have the potential to maintain energy output higher than monofacial devices under unfavorable weather conditions. A transparent back-buffer layer which can passivate the interface and improve the minority carrier lifetime is critical in CdTe-based bifacial devices. Herein, solution-processed Cu x Cr y O z as a promising back-buffer for CdTe/CdS solar cells is demonstrated. The carrier lifetimes measured at the front and back of the device are 31.2 and 3.1 ns, respectively, which correspond to an increase of ≈38% and 138%, respectively, compared to the reference device. This dramatic improvement in lifetime results in a 100% increase in short-circuit current measured with backside illumination. The best bifacial device has efficiencies 7.6% and 12.5%, respectively, from back and front illumination, yielding a bifaciality factor of 0.60.

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14 SOLAR ENERGYCdTe solar cellsCopper chromium oxideEnergy & FuelsMaterials Scienceback contactbifacial

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Pokhrel, Dipendra, Mathew, Xavier, Khanal Subedi, Kamala, Patel, Aesha, Phillips, Adam B., Bastola, Ebin, Abudulimu, Abasi, Jamarkattel, Manoj K., Rijal, Suman, Quader, Abdul, Friedl, Jared, Zawisza, Zachary, Yan, Yanfa, Heben, Michael J., Ellingson, Randy J.. 2022-08-10. Bifacial CdTe Solar Cells with Copper Chromium Oxide Back-Buffer Layer. https://doi.org/10.1002/solr.202200501

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