Publications by Lukas Pfeifer | EPFL Graph Search

Enhancing Indoor Photovoltaic Eﬃciency to 37.6% Through Triple Passivation Reassembly and n-Type to p-Type Modulation in Wide Bandgap Perovskites

Despite well‐matching indoor illumination spectra, the performance of wide bandgap perovskite solar cells (WB‐PSCs) for indoor photovoltaics (i‐PV) is hindered by photo‐induced halide phase segregation and trap‐assisted non‐radiative recombination. Herein, ...

Wiley2025

Aryl-Acetylene Layered Hybrid Perovskites in Photovoltaics

Michael Graetzel, Christophe Ballif, Ursula Röthlisberger, Aïcha Hessler-Wyser, Felix Thomas Eickemeyer, Lukas Pfeifer, Christian Michael Wolff, Virginia Carnevali, Nikolaos Lempesis, Mostafa Rabie Shlaly Bahr Othman

Metal halide perovskites have shown exceptional potential in converting solar energy to electric power in photovoltaics, yet their application is hampered by limited operational stability. This stimulated the development of hybrid layered (two-dimensional, ...

WILEY-V C H VERLAG GMBH2025

Aryl‐Acetylen‐Schichthybrid‐Perowskite in der Photovoltaik

Michael Graetzel, Ursula Röthlisberger, Felix Thomas Eickemeyer, Lukas Pfeifer, Virginia Carnevali, Nikolaos Lempesis, Fatemeh Ansari, Masaud Hassan S Almalki

Metallhalogenid‐Perowskite haben ein außerordentliches Potenzial für die Umwandlung von Sonnenenergie in elektrische Energie in der Photovoltaik gezeigt, doch ihre Anwendung wird durch eine begrenzte Betriebsstabilität behindert. Dies hat die Entwicklung h ...

Wiley2025

Dopamine Dopes the Performance of Perovskite Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Shaik Mohammed Zakeeruddin, David Lyndon Emsley, Ursula Röthlisberger, Felix Thomas Eickemeyer, Lukas Pfeifer, Virginia Carnevali, Nikolaos Lempesis

The electron transport layer (ETL) is a crucial component of perovskite solar cells (PSCs) as it greatly influences their photovoltaic performance. Among various currently used ETL materials, SnO₂ stands out due to its unique advantages, including low‐temp ...

Wiley2025

Conformationally Stable and Sterically Hindered Bicyclo[1.1.1]pentane-1,3-diammonium Modification of FAPbI3 Enhances the Performance of Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Lukas Pfeifer

Solution-processed α-FAPbI3 perovskite films frequently exhibit structural defects and impurities that impede the durable operation of solar cells. In this study, we introduced a conformationally stable, sterically bulky molecular passivator, bicyclo[1.1.1 ...

2025

Strain-induced rubidium incorporation into wide-bandgap perovskites reduces photovoltage loss

Michael Graetzel, Shaik Mohammed Zakeeruddin, David Lyndon Emsley, Ursula Röthlisberger, Mounir Driss Mensi, Felix Thomas Eickemeyer, Pascal Alexander Schouwink, Lukas Pfeifer, Jing Gao, Virginia Carnevali

A-site cation mixing can enhance the photovoltaic performance of a wide-bandgap (WBG) perovskite, but rubidium (Rb) cation mixing generally forms a nonperovskite phase. We report that lattice strain locks Rb ions into the α-phase of the lattice of a triple ...

American Association for the Advancement of Science (AAAS)2025

TEMPO bulk passivation boosts the performance and operational stability of rapid-annealed FAPI perovskite solar cells

Michael Graetzel, Kevin Sivula, Felix Thomas Eickemeyer, Lukas Pfeifer, Sandy Sanchez Alonso

In this work, we present a high-performance, stable formamidinium lead iodide (FAPI) perovskite solar cell (PSC) achieved through the use of 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) bulk passivation and rapid photonic annealing. Utilizing flash infrared ...

2025

Carbazole Treated Waterproof Perovskite Films with Improved Solar Cell Performance

Michael Graetzel, Paul Joseph Dyson, Ursula Röthlisberger, Felix Thomas Eickemeyer, Lukas Pfeifer, Virginia Carnevali, Nikolaos Lempesis, Haizhou Lu, Yeonju Kim, Jaeki Jeong

Surface passivation has been widely employed to suppress non-radiative charge recombination and prevent interfacial charge accumulation in perovskite photovoltaics. In this report, carbazole modified with ammonium iodide connected via alkyl chains of diffe ...

Wiley-V C H Verlag Gmbh2024

Improving the operational stability of perovskite solar cells with cesium-doped graphene oxide interlayer

Michael Graetzel, Shaik Mohammed Zakeeruddin, Felix Thomas Eickemeyer, Lukas Pfeifer, Christian Michael Wolff, Rita Therisod, Mostafa Rabie Shlaly Bahr Othman, Hong Zhang, Masaud Hassan S Almalki

Perovskite solar cells (PSCs) have made great advances in terms of power conversion efficiency (PCE), yet their subpar stability continues to hinder their commercialization. The interface between the perovskite layer and the charge-carrier transporting lay ...

Elsevier2024

Formamidinium Incorporates into Rb-based Non-Perovskite Phases in Solar Cell Formulations

Michael Graetzel, David Lyndon Emsley, Lukas Pfeifer, Likai Zheng, Ümmügülsüm Günes, Michael Allan Hope, Yuxuan Zhang

Organic-inorganic hybrid perovskite materials, such as formamidinium lead iodide (FAPbI3), are among the most promising emerging photovoltaic materials. However, the spontaneous phase transition from the photoactive perovskite phase to an inactive non-pero ...

Wiley-VCH Verlag GmbH2024