0000000000637265

AUTHOR

Dávid Forgács

Lead acetate precursor based p-i-n perovskite solar cells with enhanced reproducibility and low hysteresis

A low temperature approach for the fabrication of p-i-n perovskite solar cells is presented. Using lead acetate-based precursors, flat and homogeneous CH3NH3PbI3 films, compatible with the use of thin organic charge transport layers, can be obtained. The corresponding solar cells showed power conversion efficiency up to 12.5%, with remarkable reproducibility and very low hysteresis.

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Strontium Insertion in Methylammonium Lead Iodide: Long Charge Carrier Lifetime and High Fill-Factor Solar Cells.

The addition of Sr2+ in CH3 NH3 PbI3 perovskite films enhances the charge carrier collection efficiency of solar cells leading to very high fill factors, up to 85%. The charge carrier lifetime of Sr2+ -containing perovskites is in excess of 40 μs, longer than those reported for perovskite single crystals.

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Evidence of Band Bending Induced by Hole Trapping at MAPbI3 Perovskite / Metal Interface

International audience; Electron injection by tunneling from a gold electrode and hole transport properties in polycrystalline MAPbI3 has been investigated using variable temperature experiments and numerical simulations. The presence of a large and unexpected band bending at the Au/MAPbI3 interface is revealed and attributed to the trapping of holes, which enhances the injection of electrons via tunneling. These results elucidate the role of volume and interface defects in state-of-the-art hybrid perovskite semiconductors.

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Single junction and tandem perovskite solar cells

En este trabajo hemos estudiado diferentes métodos para preparar dispositivos fotovoltaicos de perovskitas. Se han cumplido los tres objetivos definidos al inicio de este periodo de investigación: 1. Hemos establecido con éxito un método estable y reproducible para la fabricación de células solares de perovskita procesadas desde disolución, empleando acetato de plomo y MAI como materiales precursores. 2. Hemos conseguido sintonizar el "bandgap" de perovskitas mixtas de bromuro y yoduro para alcanzar un valor de 2.0 eV, aprovechando las propiedades estabilizadoras de los cationes Cs+ y FA. Hemos investigado perovskitas de doble halogenuro y doble catión Cs0.15FA0.85Pb(Br0.7I0.3)3, fabricadas…

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Efficient wide band gap double cation – double halide perovskite solar cells

In this work we study the band gap variation and properties of the perovskite compound Cs0.15FA0.85Pb(BrxI1−x)3 as a function of the halide composition, with the aim of developing an efficient complementary absorber for MAPbI3 in all-perovskite tandem devices. We have found the perovskite stoichiometry Cs0.15FA0.85Pb(Br0.7I0.3)3 to be a promising candidate, thanks to its band gap of approximately 2 eV. Single junction devices using this perovskite absorber lead to a maximum PCE of 11.5%, among the highest reported for solar cells using perovskites with a band gap wider than 1.8 eV.

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Interface engineering in efficient vacuum deposited perovskite solar cells

Abstract We studied the effect of the charge transport layers in p-i-n perovskite solar cells using vacuum deposited methylammonium lead iodide thin-film absorbers. While solution-processed perovskite films are frequently deposited directly on PEDOT:PSS leading to good solar cell performances, in some cases even to very good Voc values, we show that in devices employing vacuum deposited MAPbI3 perovskites, the removal of the polyTPD electron blocker substantially reduces the photovoltaic behavior. This is indicative of rather different charge transport properties in the vacuum deposited MAPbI3 perovskites compared to those prepared from solution. On the other hand, we investigated the use o…

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