Hysteresis and Capacitive Features of Perovskite Solar Cells

In the present work, anomalous distortions occurring in the current-voltage characteristic of perovskite solar cells (PSCs), usually called J-V curve hysteresis, are studied by several methods. This includes dynamic direct current (DC) mode J-V experiments and impedance spectroscopy (IS) analyses in...

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Detalles Bibliográficos
Autor: Almora Rodríguez, Osbel
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/669272
Acceso en línea:http://hdl.handle.net/10803/669272
http://dx.doi.org/10.6035/14104.2020.603901
Access Level:acceso abierto
Palabra clave:Photovoltaic solar cells
Perovskites
Impedance spectroscopy
.Capacitance
Ionic conductivity
Light intensity modulation
Ciències naturals, químiques, físiques i matemàtiques
620
Descripción
Sumario:In the present work, anomalous distortions occurring in the current-voltage characteristic of perovskite solar cells (PSCs), usually called J-V curve hysteresis, are studied by several methods. This includes dynamic direct current (DC) mode J-V experiments and impedance spectroscopy (IS) analyses in dark and under illumination. The J-V curves of PSCs were measured under different conditions showing capacitive hysteretic currents. This is related with low frequency excess capacitance in the IS spectra. These two features are correlated with the response of mobile ions in space charge regions close to the interfaces. The large values of capacitance under illumination in the sub-Hz regime were explained in terms of mobile ions space charges and chemical capacitances assuming a proportionality between the number of ionized/activated mobile ions and the concentration of charge carriers and photon fluence.