Publications by Christian Michael Wolff

Related publications (32)

Enhancing lifetime, forecasting, and economic benefits of photovoltaic technologies undergoing UV-induced degradation with optical filtering

Christophe Ballif, Antonin Faes, Christian Michael Wolff, Marion Solange Madeleine Dussouillez

Ultraviolet-induced degradation (UV-ID) of various PV cell types was analyzed under optical UV filters with different cutoff wavelengths. Cell types studied included interdigitated back contact (IBC), passivated emitter and rear totally diffused (PERT), an ...

2025

Self-Aligned Silica Nanoparticle Rear Reflectors for Single-Junction Si and Perovskite-Si Tandem Solar Cells

Christophe Ballif, Christian Michael Wolff, Kerem Artuk, Deniz Türkay

Infrared light management is crucial to maximize the optical performance of crystalline Si-based single junction and tandem solar cells. For this end, a low refractive index dielectric is typically inserted under the rear metal and an electrical contact is ...

2025

Rationalizing Performance Losses of Wide Bandgap Perovskite Solar Cells Evident in Data from the Perovskite Database

Christian Michael Wolff, Tor Jesper Jacobsson

Metal halide perovskites (MHPs) have become a widely studied class of semiconductors for various optoelectronic devices. The possibility to tune their bandgap (E-g) over a broad spectral range from 1.2 eV to 3 eV by compositional engineering makes them par ...

Wiley-V C H Verlag Gmbh2023

Improving the photo-stability of triple cation perovskite solar cells using chromophore-infused optically transparent Pectin/polymethyl methacrylate composite

Christophe Ballif, Aïcha Hessler-Wyser, Christian Michael Wolff, Mostafa Rabie Shlaly Bahr Othman

Perovskite solar cells (PSCs) show great promise due to their high efficiency and low manufacturing costs, yet they encounter notable challenges such as optical losses and stability issues, mainly due to high surface reflection and degradation from UV irra ...

FUNDACIO DE LA COMUNITAT VALENCIANA SCITO2024

A Universal Perovskite/C60 Interface Modification via Atomic Layer Deposited Aluminum Oxide for Perovskite Solar Cells and Perovskite-Silicon Tandems

Christophe Ballif, Aïcha Hessler-Wyser, Mounir Driss Mensi, Christian Michael Wolff, Kerem Artuk, Mostafa Rabie Shlaly Bahr Othman, Deniz Türkay

The primary performance limitation in inverted perovskite-based solar cells is the interface between the fullerene-based electron transport layers and the perovskite. Atomic layer deposited thin aluminum oxide (AlOX) interlayers that reduce nonradiative re ...

Wiley-V C H Verlag Gmbh2024

Pizza Oven Processing of Organohalide Perovskites (POPOP): A Simple, Versatile and Efficient Vapor Deposition Method

Christophe Ballif, Christian Michael Wolff, Kerem Artuk, Cédric Bucher, Deniz Türkay, Austin George Kuba, Quentin Jean-Marie Armand Guesnay, Nicolas Fürst

Hybrid vapor deposition is one of the most appealing processes for perovskite photovoltaics fabrication, thanks to its versatile nature. By using sequentially different vapor deposition processes tailored to the inorganic and organic perovskite precursors' ...

Wiley-V C H Verlag Gmbh2024

Understanding and Mitigating the Degradation of Perovskite Solar Cells Based on a Nickel Oxide Hole Transport Material during Damp Heat Testing

Christophe Ballif, Kevin Sivula, Jun Ho Yum, Mounir Driss Mensi, Yongpeng Liu, Christian Michael Wolff, Marion Solange Madeleine Dussouillez

The development of stable materials, processable on alarge area,is a prerequisite for perovskite industrialization. Beyond the perovskiteabsorber itself, this should also guide the development of all otherlayers in the solar cell. In this regard, the use o ...

AMER CHEMICAL SOC2023

Laser Patterned Flexible 4T Perovskite-Cu(In,Ga)Se-2 Tandem Mini-module with Over 18% Efficiency

Christian Michael Wolff, Kerem Artuk

Perovskite-Cu(In,Ga)Se-2 (CIGS) thin-film tandem technology provides an exciting prospect to achieve low-cost high-efficiency photovoltaic devices by high throughput roll-to-roll processing on flexible substrates. However, no report on flexible perovskite- ...

WILEY-V C H VERLAG GMBH2022

Blade-Coating of High Crystallinity Cesium-Formamidinium Perovskite Formulations

Anaël Morgane Jaffrès, Christophe Ballif, Aïcha Hessler-Wyser, Christian Michael Wolff, Mostafa Rabie Shlaly Bahr Othman

Up-scalable coating processes need to be developed to manufacture efficient and stable perovskite-based solar modules. In this work, we combine two Lewis base additives (N,N′-dimethylpropyleneurea and thiourea) to fabricate high-quality Cs0.15FA0.85PbI3 pe ...

2024

Lateral ion migration accelerates degradation in halide perovskite devices

Christophe Ballif, Quentin Thomas Jeangros, Kerem Artuk, Christian Michael Wolff, Xin Yu Chin, Daniel Anthony Jacobs

The migration of mobile ions has long been considered a source of performance degradation in devices based on halide perovskites, but details regarding the mechanisms and extent of this problem remain scarce. Here we report the finding that differences in ...

ROYAL SOC CHEMISTRY2022

Nano-emitting Heterostructures Violate Optical Reciprocity and Enable Efficient Photoluminescence in Halide-Segregated Methylammonium-Free Wide Bandgap Perovskites

Christophe Ballif, Quentin Thomas Jeangros, Chien-Jen Yang, Christian Michael Wolff, Peter Joseph Fiala

This work investigates halide segregation in methylammonium-free wide bandgap perovskites by photoluminescence quantum yield (PLQY) and advanced electron microscopy techniques. Our study reveals how the formation of nano-emitting low-energy domains embedde ...

AMER CHEMICAL SOC2021

Synergetic substrate and additive engineering for over 30%-efficient perovskite-Si tandem solar cells

Christophe Ballif, Mathieu Gérard Boccard, Quentin Thomas Jeangros, Mounir Driss Mensi, Christian Michael Wolff, Kerem Artuk, Deniz Türkay, Daniel Anthony Jacobs, Xin Yu Chin

Perovskite-silicon (Si) tandem solar cells are the most prominent contenders to succeed single-junction Si cells that dominate the market today. Yet, to justify the added cost of inserting a perovskite cell on top of Si, these devices should first exhibit ...

2024

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

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

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

Assessing the Influence of Illumination on Ion Conductivity in Perovskite Solar Cells

Christophe Ballif, Aïcha Hessler-Wyser, Christian Michael Wolff, Mostafa Rabie Shlaly Bahr Othman

Whether illumination influences the ion conductivity in lead-halide perovskite solar cells containing iodide halides has been an ongoing debate. Experiments to elucidate the presence of a photoconductive effect require special devices or measurement techni ...

2024

In Situ Buried Interface Engineering towards Printable Pb−Sn Perovskite Solar Cells

Christian Michael Wolff, Fan Fu

High-efficiency Pb−Sn narrow-bandgap perovskite solar cells (PSCs) heavily rely on PEDOT:PSS as the hole-transport layer (HTL) owing to its excellent electrical conductivity, dopant-free nature, and facile solution processability. However, the shallow work ...

American Chemical Society (ACS)2024

Bi-functional interfaces by poly(ionic liquid) treatment in efficient pin and nip perovskite solar cells

Mohammad Khaja Nazeeruddin, Antonio Abate, Giulia Grancini, Albertus Adrian Sutanto, Christian Michael Wolff

Approaches to boost the efficiency and stability of perovskite solar cells often address one singular problem in a specific device configuration. In this work, we utilize a poly(ionic liquid) (PIL) to introduce a multi-functional interlayer to improve the ...

ROYAL SOC CHEMISTRY2021

Correlating light-induced deep defects and phase segregation in mixed-halide perovskites

Quentin Thomas Jeangros, Jakub Holovsky, Christian Michael Wolff, Peter Joseph Fiala, Xin Yu Chin

Mixed-halide perovskites are highly promising materials for tandem solar cells. The phenomenon of phase segregation, however hinders their application. Here, we combine Fourier-Transform photocurrent spectroscopy with photoluminescence and current density- ...

Royal Society of Chemistry2022

Template-Assisted Growth of CsxFA1-xPbI3 with Pulsed Laser Deposition for Single Junction Perovskite Solar Cells

Christian Michael Wolff, Kerem Artuk

Cesium-formamidinium lead iodide (CsxFA1-xPbI3) perovskites are a promising methylammonium-free alternative for efficient single-junction solar cells. However, they have not been fully explored by vapor-phase deposition techniques. Herein, a template-assis ...

2025

Perovskite/Silicon Tandem Solar Cells Above 30% Conversion Efficiency on Submicron-Sized Textured Czochralski-Silicon Bottom Cells with Improved Hole-Transport Layers

Christophe Ballif, Christian Michael Wolff, Kerem Artuk

In perovskite/silicon tandem solar cells, the utilization of silicon heterojunction (SHJ) solar cells as bottom cells is one of the most promising concepts. Here, we present optimization strategies for the top cell processing and their integration into SHJ ...

2024

Interface passivation for 31.25%-efficient perovskite/silicon tandem solar cells

Christophe Ballif, Mathieu Gérard Boccard, Quentin Thomas Jeangros, Mounir Driss Mensi, Christian Michael Wolff, Kerem Artuk, Deniz Türkay, Peter Joseph Fiala, Daniel Anthony Jacobs, Quentin Jean-Marie Armand Guesnay, Xin Yu Chin

Silicon solar cells are approaching their theoretical efficiency limit of 29%. This limitation can be exceeded with advanced device architectures, where two or more solar cells are stacked to improve the harvesting of solar energy. In this work, we devise ...

American Association for the Advancement of Science2023