Utilization of Temperature-Sweeping Capacitive Techniques to Evaluate Band Gap Defect Densities in Photovoltaic Perovskites

Journal article
(Letter)


Publication Details

Author(s): Almora Rodriguez O, García-Batlle M, Garcia-Belmonte G
Journal: Journal of Physical Chemistry Letters
Publication year: 2019
Volume: 10
Pages range: 3661-3669
ISSN: 1948-7185


Abstract

Capacitive techniques, routinely used for solar cell parameter extraction, probe the voltage-modulation of the depletion layer capacitance isothermally as well as under varying temperature. Also defect states within the semiconductor band-gap respond to such stimuli. Although extensively used, capacitive methods have found difficulties when applied to elucidate bulk defect bands in photovoltaic perovskites. This is so because perovskite solar cells (PSCs) actually exhibit some intriguing capacitive features hardly connected to electronic defect dynamics. The commonly reported excess capacitance observed at low frequencies is originated by outer interface mechanisms and has a direct repercussion on the evaluation of band-gap defect levels. Starting by updating previous observations on Mott-Schottky (MS) analysis in PSCs, it is discussed how the thermal admittance spectroscopy (TAS) and the deep level transient spectroscopy (DLTS) characterization techniques present spectra with overlapping or even “fake” peaks caused by the mobile ion-related, interfacial excess capacitance. These capacitive techniques, when used uncritically, may be misleading and produce wrong outcomes.


FAU Authors / FAU Editors

Almora Rodriguez, Osbel
Institute Materials for Electronics and Energy Technology (i-MEET)


Additional Organisation
Erlangen Graduate School in Advanced Optical Technologies


External institutions with authors

Universitat Jaume I (UJI)


How to cite

APA:
Almora Rodriguez, O., García-Batlle, M., & Garcia-Belmonte, G. (2019). Utilization of Temperature-Sweeping Capacitive Techniques to Evaluate Band Gap Defect Densities in Photovoltaic Perovskites. Journal of Physical Chemistry Letters, 10, 3661-3669. https://dx.doi.org/10.1021/acs.jpclett.9b00601

MLA:
Almora Rodriguez, Osbel, Marisé García-Batlle, and Germà Garcia-Belmonte. "Utilization of Temperature-Sweeping Capacitive Techniques to Evaluate Band Gap Defect Densities in Photovoltaic Perovskites." Journal of Physical Chemistry Letters 10 (2019): 3661-3669.

BibTeX: 

Last updated on 2019-19-06 at 15:23