Bitte benutzen Sie diese Kennung, um auf die Ressource zu verweisen:
https://doi.org/10.21256/zhaw-22628| Publikationstyp: | Beitrag in wissenschaftlicher Zeitschrift |
| Art der Begutachtung: | Peer review (Publikation) |
| Titel: | When photoluminescence, electroluminescence, and open-circuit voltage diverge : light soaking and halide segregation in perovskite solar cells |
| Autor/-in: | Ebadi Garjan, Firouzeh Yang, Bowen Kim, YeonJu Mohammadpour, Raheleh Taghavinia, Nima Hagfeldt, Anders Tress, Wolfgang |
| et. al: | No |
| DOI: | 10.1039/D1TA02878B 10.21256/zhaw-22628 |
| Erschienen in: | Journal of Materials Chemistry A |
| Band(Heft): | 9 |
| Heft: | 24 |
| Seite(n): | 13967 |
| Seiten bis: | 13978 |
| Erscheinungsdatum: | 4-Jun-2021 |
| Verlag / Hrsg. Institution: | Royal Society of Chemistry |
| ISSN: | 2050-7488 2050-7496 |
| Sprache: | Englisch |
| Fachgebiet (DDC): | 621.3: Elektro-, Kommunikations-, Steuerungs- und Regelungstechnik |
| Zusammenfassung: | Perovskite solar cells suffer from various instabilities on all time scales. Some of them are driven by light, in particular when employing compounds with mixed halides. Such light soaking effects have been observed in performance changes of solar-cell devices. They have also been spectroscopically investigated in detail on films, where the formation of a low-gap iodine rich phase, seen in a red shift of the PL has been made responsible for a reduced open-circuit voltage. However, studies synchronously examining device performance and its relation to spectroscopy data, are scarce. Here, we perform an in-operandum study, where we investigate changes of open-circuit voltage (Voc) and photocurrent during light soaking and complement it with photo- (PL) and electroluminescence (EL) data on devices, which allow analysis of the Voc-limiting processes using optical and optoelectronic reciprocity relations. We find that changes in the Voc for stable single halide compositions are quantitatively correlated with changes in the PL intensity, showing that the Voc follows changes in the quasi-Fermi level splitting. In contrast, changes in Voc for the mixed halide composition are not correlated to the emergence of the low-gap phase, confirming that this phase is not the sole culprit for a low and instable Voc. Instead, non-radiative voltage losses influenced by mobile ions are dominant in devices containing compositions with high Br content. Interestingly, the low-gap phase contributes less to photocurrent, as seen by a wavelength-dependent PL quenching at short circuit. This observation might be explained by the formation of emissive but partially insulated iodine-rich regions in the film. Such an effect is also possible for single halide systems, when the perovskite composition is not stable, seen in an increase of PL at short circuit during light soaking. This indicates that ion migration in general causes photovoltaically inactive regions, without enhancing non-radiative recombination. EL measurements confirm that Rau’s reciprocity relation between external EL quantum efficiency and Voc cannot readily be applied to absorbers with such different phases. Perovskite solar cells suffer from various instabilities on all time scales. Some of them are driven by light, in particular when employing compounds with mixed halides. Such light soaking effects have been observed in performance changes of solar-cell devices. They have also been spectroscopically investigated in detail on films, where the formation of a low-gap iodine rich phase, seen in a red shift of the PL has been made responsible for a reduced open-circuit voltage. However, studies synchronously examining device performance and its relation to spectroscopy data, are scarce. Here, we perform an in-operandum study, where we investigate changes of open-circuit voltage (Voc) and photocurrent during light soaking and complement it with photo- (PL) and electroluminescence (EL) data on devices, which allow analysis of the Voc-limiting processes using optical and optoelectronic reciprocity relations. We find that changes in the Voc for stable single halide compositions are quantitatively correlated with changes in the PL intensity, showing that the Voc follows changes in the quasi-Fermi level splitting. In contrast, changes in Voc for the mixed halide composition are not correlated to the emergence of the low-gap phase, confirming that this phase is not the sole culprit for a low and instable Voc. Instead, non-radiative voltage losses influenced by mobile ions are dominant in devices containing compositions with high Br content. Interestingly, the low-gap phase contributes less to photocurrent, as seen by a wavelength-dependent PL quenching at short circuit. This observation might be explained by the formation of emissive but partially insulated iodine-rich regions in the film. Such an effect is also possible for single halide systems, when the perovskite composition is not stable, seen in an increase of PL at short circuit during light soaking. This indicates that ion migration in general causes photovoltaically inactive regions, without enhancing non-radiative recombination. EL measurements confirm that Rau’s reciprocity relation between external EL quantum efficiency and Voc cannot readily be applied to absorbers with such different phases. |
| URI: | https://digitalcollection.zhaw.ch/handle/11475/22628 |
| Volltext Version: | Akzeptierte Version |
| Lizenz (gemäss Verlagsvertrag): | Lizenz gemäss Verlagsvertrag |
| Gesperrt bis: | 2022-06-05 |
| Departement: | School of Engineering |
| Organisationseinheit: | Institute of Computational Physics (ICP) |
| Publiziert im Rahmen des ZHAW-Projekts: | Modellierung und Charakterisierung von neuartigen optoelektronischen Bauelementen |
| Enthalten in den Sammlungen: | Publikationen School of Engineering |
Dateien zu dieser Ressource:
| Datei | Beschreibung | Größe | Format | |
|---|---|---|---|---|
| 2021_Ebadi-etal_Photoluminescence-electroluminescence-and-open-circuit-voltage.pdf | Accepted Version | 1.66 MB | Adobe PDF |  Öffnen/Anzeigen |
Zur Langanzeige
Ebadi Garjan, F., Yang, B., Kim, Y., Mohammadpour, R., Taghavinia, N., Hagfeldt, A., & Tress, W. (2021). When photoluminescence, electroluminescence, and open-circuit voltage diverge : light soaking and halide segregation in perovskite solar cells. Journal of Materials Chemistry A, 9(24), 13967–13978. https://doi.org/10.1039/D1TA02878B
Ebadi Garjan, F. et al. (2021) ‘When photoluminescence, electroluminescence, and open-circuit voltage diverge : light soaking and halide segregation in perovskite solar cells’, Journal of Materials Chemistry A, 9(24), pp. 13967–13978. Available at: https://doi.org/10.1039/D1TA02878B.
F. Ebadi Garjan et al., “When photoluminescence, electroluminescence, and open-circuit voltage diverge : light soaking and halide segregation in perovskite solar cells,” Journal of Materials Chemistry A, vol. 9, no. 24, pp. 13967–13978, Jun. 2021, doi: 10.1039/D1TA02878B.
EBADI GARJAN, Firouzeh, Bowen YANG, YeonJu KIM, Raheleh MOHAMMADPOUR, Nima TAGHAVINIA, Anders HAGFELDT und Wolfgang TRESS, 2021. When photoluminescence, electroluminescence, and open-circuit voltage diverge : light soaking and halide segregation in perovskite solar cells. Journal of Materials Chemistry A. 4 Juni 2021. Bd. 9, Nr. 24, S. 13967–13978. DOI 10.1039/D1TA02878B
Ebadi Garjan, Firouzeh, Bowen Yang, YeonJu Kim, Raheleh Mohammadpour, Nima Taghavinia, Anders Hagfeldt, and Wolfgang Tress. 2021. “When Photoluminescence, Electroluminescence, and Open-Circuit Voltage Diverge : Light Soaking and Halide Segregation in Perovskite Solar Cells.” Journal of Materials Chemistry A 9 (24): 13967–78. https://doi.org/10.1039/D1TA02878B.
Ebadi Garjan, Firouzeh, et al. “When Photoluminescence, Electroluminescence, and Open-Circuit Voltage Diverge : Light Soaking and Halide Segregation in Perovskite Solar Cells.” Journal of Materials Chemistry A, vol. 9, no. 24, June 2021, pp. 13967–78, https://doi.org/10.1039/D1TA02878B.
Alle Ressourcen in diesem Repository sind urheberrechtlich geschützt, soweit nicht anderweitig angezeigt.