Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon
Long diffusion lengths of photoexcited charge carriers are crucial for high power conversion efficiencies of photoelectrochemical and photovoltaic devices. Time-resolved photoconductance measurements are often used to determine diffusion lengths in conventional semiconductors. However, effects such...
Saved in:
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2022-09-01
|
| Series: | PRX Energy |
| Online Access: | http://doi.org/10.1103/PRXEnergy.1.023008 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850262088410202112 |
|---|---|
| author | Markus Schleuning Moritz Kölbach Fatwa F. Abdi Klaus Schwarzburg Martin Stolterfoht Rainer Eichberger Roel van de Krol Dennis Friedrich Hannes Hempel |
| author_facet | Markus Schleuning Moritz Kölbach Fatwa F. Abdi Klaus Schwarzburg Martin Stolterfoht Rainer Eichberger Roel van de Krol Dennis Friedrich Hannes Hempel |
| author_sort | Markus Schleuning |
| collection | DOAJ |
| description | Long diffusion lengths of photoexcited charge carriers are crucial for high power conversion efficiencies of photoelectrochemical and photovoltaic devices. Time-resolved photoconductance measurements are often used to determine diffusion lengths in conventional semiconductors. However, effects such as polaron formation or multiple trapping can lead to time-varying mobilities and lifetimes that are not accounted for in the conventional calculation of the diffusion length. Here, a generalized analysis is presented that is valid for time-dependent mobilities and time-dependent lifetimes. The diffusion length is determined directly from the integral of a photoconductivity transient and can be applied regardless of the nature of carrier relaxation. To demonstrate our approach, photoconductivity transients are measured from 100 fs to 1 µs by the combination of time-resolved terahertz and microwave spectroscopy for BiVO_{4}, one of the most studied metal oxide photoanodes for photoelectrochemical water splitting. The temporal evolution of charge carrier displacement is monitored and converges after about 100 ns to a diffusion length of about 15 nm, which rationalizes the photocurrent loss in the corresponding photoelectrochemical device. The presented method is further validated on a-Si:H, c-Si, and halide perovskite, which underlines its potential to determine the diffusion length in a wide range of semiconductors, including disordered materials. |
| format | Article |
| id | doaj-art-d850a8eb1dbc4cfab0ed8feebc0f89d2 |
| institution | OA Journals |
| issn | 2768-5608 |
| language | English |
| publishDate | 2022-09-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | PRX Energy |
| spelling | doaj-art-d850a8eb1dbc4cfab0ed8feebc0f89d22025-08-20T01:55:15ZengAmerican Physical SocietyPRX Energy2768-56082022-09-011202300810.1103/PRXEnergy.1.023008Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline SiliconMarkus SchleuningMoritz KölbachFatwa F. AbdiKlaus SchwarzburgMartin StolterfohtRainer EichbergerRoel van de KrolDennis FriedrichHannes HempelLong diffusion lengths of photoexcited charge carriers are crucial for high power conversion efficiencies of photoelectrochemical and photovoltaic devices. Time-resolved photoconductance measurements are often used to determine diffusion lengths in conventional semiconductors. However, effects such as polaron formation or multiple trapping can lead to time-varying mobilities and lifetimes that are not accounted for in the conventional calculation of the diffusion length. Here, a generalized analysis is presented that is valid for time-dependent mobilities and time-dependent lifetimes. The diffusion length is determined directly from the integral of a photoconductivity transient and can be applied regardless of the nature of carrier relaxation. To demonstrate our approach, photoconductivity transients are measured from 100 fs to 1 µs by the combination of time-resolved terahertz and microwave spectroscopy for BiVO_{4}, one of the most studied metal oxide photoanodes for photoelectrochemical water splitting. The temporal evolution of charge carrier displacement is monitored and converges after about 100 ns to a diffusion length of about 15 nm, which rationalizes the photocurrent loss in the corresponding photoelectrochemical device. The presented method is further validated on a-Si:H, c-Si, and halide perovskite, which underlines its potential to determine the diffusion length in a wide range of semiconductors, including disordered materials.http://doi.org/10.1103/PRXEnergy.1.023008 |
| spellingShingle | Markus Schleuning Moritz Kölbach Fatwa F. Abdi Klaus Schwarzburg Martin Stolterfoht Rainer Eichberger Roel van de Krol Dennis Friedrich Hannes Hempel Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon PRX Energy |
| title | Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon |
| title_full | Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon |
| title_fullStr | Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon |
| title_full_unstemmed | Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon |
| title_short | Generalized Method to Extract Carrier Diffusion Length from Photoconductivity Transients: Cases of BiVO_{4}, Halide Perovskites, and Amorphous and Crystalline Silicon |
| title_sort | generalized method to extract carrier diffusion length from photoconductivity transients cases of bivo 4 halide perovskites and amorphous and crystalline silicon |
| url | http://doi.org/10.1103/PRXEnergy.1.023008 |
| work_keys_str_mv | AT markusschleuning generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT moritzkolbach generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT fatwafabdi generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT klausschwarzburg generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT martinstolterfoht generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT rainereichberger generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT roelvandekrol generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT dennisfriedrich generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon AT hanneshempel generalizedmethodtoextractcarrierdiffusionlengthfromphotoconductivitytransientscasesofbivo4halideperovskitesandamorphousandcrystallinesilicon |