Publications de Florent Sahli | EPFL Graph Search

Vapor deposition of metal halide perovskite thin films: Process control strategies to shape layer properties

Christophe Ballif, Quentin Thomas Jeangros, Florent Sahli, Quentin Jean-Marie Armand Guesnay

Vapor-based processes are particularly promising to deposit the perovskite thin film absorber of solar cells. These deposition methods are up-scalable, involve a controlled solvent-free environment, have the ability to conformally coat rough substrates, in ...

2021

Vapor Transport Deposition of Methylammonium Iodide for Perovskite Solar Cells

Christophe Ballif, Quentin Thomas Jeangros, Cédric Bucher, Florent Sahli, Léo Duchêne, Björn Niesen, Aymeric Michel Schafflützel, Nathanaël Miaz, Quentin Jean-Marie Armand Guesnay, Niccolo Salsi

Vapor-based processes are promising options to deposit metal halide perovskite solar cells in an industrial environment due to their ability to deposit uniform layers over large areas in a controlled environment without resorting to the use of (possibly to ...

2021

Multimodal Microscale Imaging of Textured Perovskite-Silicon Tandem Solar Cells

Christophe Ballif, Quentin Thomas Jeangros, Jérémie Werner, Florent Sahli, Chien-Jen Yang, Fan Fu, Alan Richard Bowman

Halide perovskite/crystalline silicon (c-Si) tandem solar cells promise power conversion efficiencies beyond the limits of single-junction cells. However, the local light-matter interactions of the perovskite material embedded in this pyramidal multijuncti ...

AMER CHEMICAL SOC2021

Instability of p-i-n perovskite solar cells under reverse bias

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Arnaud Walter, Florent Sahli, Peter Joseph Fiala, Chien-Jen Yang, Fan Fu, Marion Solange Madeleine Dussouillez, Ricardo Augusto Zanotto Razera, Daniel Anthony Jacobs

Partial shading can trigger permanent damage in photovoltaic modules because the illuminated solar cells drive the shaded cells into reverse bias. Under reverse bias conditions, perovskite solar cells have been shown to degrade quickly due to processes tha ...

Royal Society of Chemistry2020

Development of Highly Efficient Perovskite-on-Silicon Tandem Solar Cells

Florent Sahli

Crystalline Silicon (c-Si) solar cells are dominating the photovoltaic (PV) market. Owing to their large manufacturing capacity, reliability and efficiency, c-Si solar cells are now cost-competitive with other non-renewable electricity sources in many plac ...

EPFL2020

25.1%-Efficient Monolithic Perovskite/Silicon Tandem Solar Cell Based on a p-type Monocrystalline Textured Silicon Wafer and High-Temperature Passivating Contacts

Christophe Ballif, Quentin Thomas Jeangros, Franz-Josef Haug, Mathieu Gérard Boccard, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Gizem Nogay, Andrea Ingenito

2019

Light Management: A Key Concept in High-Efficiency Perovskite/Silicon Tandem Photovoltaics

Christophe Ballif, Florent Sahli, Daniel Anthony Jacobs

The remarkable recent progress in perovskite photovoltaics affords a novel opportunity to advance the power conversion efficiency of market-dominating crystalline silicon (c-Si) solar cells. A severe limiting factor in the development of perovskite/c-Si ta ...

AMER CHEMICAL SOC2019

Solar Water Splitting with Perovskite/Silicon Tandem Cell and TiC-Supported Pt Nanocluster Electrocatalyst

Christophe Ballif, Michael Graetzel, Shaik Mohammed Zakeeruddin, Quentin Thomas Jeangros, Jérémie Werner, Florent Sahli, Jingshan Luo, Dan Ren, Jing Gao

Developing efficient, stable, and cost-effective photosystems to split water into hydrogen and oxygen using sunlight is of paramount importance for future production of fuels and chemicals from renewable sources. However, the high cost of current systems l ...

2019

Perovskite/Perovskite/Silicon Monolithic Triple-Junction Solar Cells with a Fully Textured Design

Christophe Ballif, Sylvain Nicolay, Quentin Thomas Jeangros, Arnaud Walter, Jérémie Werner, Florent Sahli, Björn Niesen, Fan Fu

High efficiency triple-junction solar cells are currently made of III−V semiconductors using expensive deposition methods. Perovskite/perovskite/silicon monolithic triple-junction solar cells could be a lower-cost alternative as no epitaxial growth is requ ...

2018

Complex Refractive Indices of Cesium–Formamidinium-Based Mixed-Halide Perovskites with Optical Band Gaps from 1.5 to 1.8 eV

Christophe Ballif, Sylvain Nicolay, Quentin Thomas Jeangros, Gabriel Christmann, Arnaud Walter, Jérémie Werner, Florent Sahli, Björn Niesen, Gizem Nogay, Philipp Friedrich Hermann Löper, Matthias Wolfgang Bräuninger, Peter Joseph Fiala, Chien-Jen Yang

Cesium-formamidinium-based mixed-halide perovskite materials with optical band gaps ranging from 1.5 to 1.8 eV are investigated by variable-angle spectroscopic ellipsometry. The determined complex refractive indices are shown to depend on the fabrication p ...

2018

Individualized prediction of the risk of liver-related death in patients with alcoholic cirrhosis

Florent Sahli, Eric Tremblay

ELSEVIER SCIENCE BV2018

Fully textured monolithic perovskite/silicon tandem solar cells with 25.2% power conversion efficiency

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Davide Sacchetto, Mathieu Gérard Boccard, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Raphaël Monnard, Gianluca Cattaneo, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Matthias Wolfgang Bräuninger

Tandem devices combining perovskite and silicon solar cells are promising candidates to achieve power conversion efficiencies above 30% at reasonable costs. State-of-the-art monolithic two-terminal perovskite/silicon tandem devices have so far featured sil ...

2018

Hybrid sequential deposition process for fully textured perovskite/silicon tandem solar cells

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Soo-Jin Moon, Arnaud Walter, Davide Sacchetto, Mathieu Gérard Boccard, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Raphaël Monnard, Monica Morales Masis, Gianluca Cattaneo, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Gizem Nogay, Oscar Esteban Rucavado Leandro, Matthias Wolfgang Bräuninger, Peter Joseph Fiala, Chien-Jen Yang, Fan Fu

Tandem solar cells that feature a high-bandgap perovskite cell on top of a lower bandgap silicon cell have the potential to reach efficiencies > 30%. Here, we present a versatile hybrid deposition method that yields conformal perovskite cells directly on t ...

IEEE2018

Spectrally resolved nonlinearity and temperature dependence of perovskite solar cells

Christophe Ballif, Jérémie Werner, Florent Sahli, Björn Niesen, Matthias Wolfgang Bräuninger

An accurate electrical device characterization of hybrid organic-inorganic halide perovskite solar cells (PSCs) is an important prerequisite for further improvement and industrial transfer of this promising photovoltaic technology. In this work, we study t ...

Elsevier2017

Imaging the Spatial Evolution of Degradation in Perovskite/Si Tandem Solar Cells After Exposure to Humid Air

Christophe Ballif, Stefaan De Wolf, Jérémie Werner, Florent Sahli, Björn Niesen, Randall Ellingson

Monolithically integrated two-terminal perovskite/Si tandem solar cells promise to achieve high power conversion efficiency. However, there is a concern that the stability of the perovskite top cell will limit the long-term performance of tandem devices. T ...

Ieee-Inst Electrical Electronics Engineers Inc2017

Improved Optics in Monolithic Perovskite/Silicon Tandem Solar Cells with a Nanocrystalline Silicon Recombination Junction

Christophe Ballif, Aïcha Hessler-Wyser, Sylvain Nicolay, Quentin Thomas Jeangros, Stefaan De Wolf, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Raphaël Monnard, Johannes Peter Seif, Andrea Tomasi, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Matthias Wolfgang Bräuninger

Perovskite/silicon tandem solar cells are increasingly recognized as promi-sing candidates for next-generation photovoltaics with performance beyond the single-junction limit at potentially low production costs. Current designs for monolithic tandems rely ...

2017

Probing Photocurrent Nonuniformities in the Subcells of Monolithic Perovskite/Silicon Tandem Solar Cells

Christophe Ballif, Stefaan De Wolf, Jérémie Werner, Florent Sahli, Björn Niesen, Randall Ellingson

Perovskite/silicon tandem solar cells with high power conversion efficiencies have the potential to become a commercially viable photovoltaic option in the near future. However, device design and optimization is challenging because conventional characteriz ...

Amer Chemical Soc2016

Transparent Electrodes in Silicon Heterojunction Solar Cells: Influence on Contact Passivation

Christophe Ballif, Sylvain Nicolay, Stefaan De Wolf, Florent Sahli, Loris Barraud, Johannes Peter Seif, Lorenzo Fanni, Andrea Tomasi, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Silvia Martin de Nicolas Agut

Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Efficient Near-Infrared-Transparent Perovskite Solar Cells Enabling Direct Comparison of 4-Terminal and Monolithic Perovskite/Silicon Tandem Cells

Christophe Ballif, Sylvain Nicolay, Soo-Jin Moon, Arnaud Walter, Davide Sacchetto, Nicolas Tétreault, Stefaan De Wolf, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Matthias Wolfgang Bräuninger

Combining market-proven silicon solar cell technology with an efficient wide band gap top cell into a tandem device is an attractive approach to reduce the cost of photovoltaic systems. For this, perovskite solar cells are promising high-efficiency top cel ...

Amer Chemical Soc2016