Publications de Nikolaos Lempesis

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

All-perovskite tandem solar cells achieving >29% efficiency with improved (100) orientation in wide-bandgap perovskites

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Virginia Carnevali, Nikolaos Lempesis, Lorenzo Agosta, Mingyang Wei

Monolithic all-perovskite tandem solar cells present a promising approach for exceeding the efficiency limit of single-junction solar cells. However, the substantial open-circuit voltage loss in the wide-bandgap perovskite subcell hinders further improveme ...

NATURE PORTFOLIO2025

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

Nanoscale size effects in α-FAPbI3 evinced by large-scale ab initio simulations

Virginia Carnevali, Nikolaos Lempesis

FUNDACIO DE LA COMUNITAT VALENCIANA SCITO2025

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

On the Accessibility of Higher-n Phases in Formamidinium-based Ruddlesden-popper and Dion-jacobson Layered Hybrid Perovskites

Michael Graetzel, Ursula Röthlisberger, Pascal Alexander Schouwink, Virginia Carnevali, Nikolaos Lempesis, Lorenzo Agosta, Masaud Hassan S Almalki

Layered (2D) hybrid perovskites offer a promising alternative for stabilizing halide perovskite materials, with a growing interest in formamidinium (FA(+)) lead iodide derivatives for photovoltaics due to their exceptional optoelectronic properties. While ...

WILEY2025

Suppression of Stacking Faults for Stable Formamidinium-Rich Perovskite Absorbers

Christophe Ballif, Ursula Röthlisberger, Aïcha Hessler-Wyser, Christian Michael Wolff, Virginia Carnevali, Nikolaos Lempesis, Lorenzo Agosta, Austin George Kuba, Mostafa Rabie Shlaly Bahr Othman, Kerem Artuk

The poor intrinsic perovskite absorber stability is arguably a central limitation challenging the prospect of commercialization for photovoltaic (PV) applications. Understanding the nanoscopic structural features that trigger instabilities in perovskite ma ...

WILEY-V C H VERLAG GMBH2025

A chemically bonded monolayer interface enables enhanced thermal stability and efficiency in Pb-Sn perovskite solar cells

Ursula Röthlisberger, Virginia Carnevali, Nikolaos Lempesis

Advances in narrow-band-gap (NBG) mixed lead-tin (Pb-Sn) perovskites have enabled increasingly efficient all-perovskite tandem solar cells, yet device stability remains limited by acidic poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) hol ...

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