Quantifying the Absorption Onset in the Quantum Efficiency of Emerging Photovoltaic Devices

Almora O, Cabrera CI, García Cerrillo J, Kirchartz T, Rau U, Brabec C (2021)

Publication Type: Journal article

Publication year: 2021

Journal

Advanced Energy Materials Wiley

DOI: 10.1002/aenm.202100022

Abstract

The external quantum efficiency (EQE), also known as incident-photon-to-collected-electron spectra are typically used to access the energy dependent photocurrent losses for photovoltaic devices. The integral over the EQE spectrum results in the theoretical short-circuit current under a given incident illumination spectrum. Additionally, one can also estimate the photovoltaic bandgap energy (Eg) from the inflection point in the absorption threshold region. The latter has recently been implemented in the “Emerging PV reports,” where the highest power conversion efficiencies are listed for different application categories, as a function of Eg. Furthermore, the device performance is put into perspective thereby relating it to the corresponding theoretical limit in the Shockley–Queisser (SQ) model. Here, the evaluation of the EQE spectrum through the sigmoid function is discussed and proven to effectively report the Eg value and the sigmoid wavelength range λs, which quantifies the steepness of the absorption onset. It is also shown how EQE spectra with large λs indicate significant photovoltage losses and present the corresponding implications on the photocurrent SQ model. Similarly, the difference between the photovoltaic and optical bandgap is analyzed in terms of λs.

Authors with CRIS profile

José García Cerrillo Institute Materials for Electronics and Energy Technology (i-MEET) Christoph Brabec Institute Materials for Electronics and Energy Technology (i-MEET)

Additional Organisation(s)

Erlangen Graduate School in Advanced Optical Technologies

Related research project(s)

Projekt E IGK 2495: Energy conversion systems: From Materials to Devices, Teilprojekt E: Lead-Free Perovskite Semiconductors with Tunable Bandgap for Energy Conversion (Projekt E IGK 2495) Jan. 1, 2020 - June 30, 2024

Involved external institutions

Universitat Jaume I (UJI) ES Spain (ES) Forschungszentrum Jülich / Research Centre Jülich (FZJ) DE Germany (DE) Zacatecano Council of Science, Technology and Innovation / Consejo Zacatecano de Ciencia, Tecnología e Innovación MX Mexico (MX)

How to cite

APA:

Almora, O., Cabrera, C.I., García Cerrillo, J., Kirchartz, T., Rau, U., & Brabec, C. (2021). Quantifying the Absorption Onset in the Quantum Efficiency of Emerging Photovoltaic Devices. Advanced Energy Materials. https://dx.doi.org/10.1002/aenm.202100022

MLA:

Almora, Osbel, et al. "Quantifying the Absorption Onset in the Quantum Efficiency of Emerging Photovoltaic Devices." Advanced Energy Materials (2021).

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