Publications by Christophe Ballif

Beyond Flat: Undulated Perovskite Solar Cells on Microscale Si Pyramids by Solution Processing

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

Microscale pyramids of silicon solar cells are often considered incompatible with solution-processed perovskite films. Thus, solution processing has mainly been used with submicron pyramids that are buried under thick perovskite films with flattened front ...

AMER CHEMICAL SOC2025

A Spatiotemporal analysis of photovoltaic electricity storage potential in electric vehicles

Christophe Ballif, Nicolas Würsch, Alejandro Pena Bello, Noémie Alice Yvonne Ségolène Jeannin, Jérémy Dumoulin

Decarbonizing mobility and integrating more renewable sources in electricity production are necessary levers to meet the climate targets. Coupling electric vehicle (EV) charging with photovoltaic (PV) electricity generation could help to provide clean elec ...

Aalborg University2025

Aryl-Acetylene Layered Hybrid Perovskites in Photovoltaics

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

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

Accelerating Optimization of Halide Perovskites: Two Blueprints for Automation

Christophe Ballif, Daniel Anthony Jacobs, Christian Michael Wolff

The fine-tuning of halide perovskite materials for both performance and stability calls for innovative tools that streamline high-throughput experimentation. Here, we present two complementary systems designed to accelerate the development of solution-proc ...

2025

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

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

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

Optimizing photon capture: advancements in amorphous silicon-based microchannel plates

Christophe Ballif, Claudio Bruschini, Edoardo Charbon, Nicolas Würsch, Luca Massimiliano Antognini, Samira Alexandra Frey, Emanuele Ripiccini

Microchannel plates are electron multipliers widely used in applications such as particle detection, imaging, or mass spectrometry and are often paired with a photocathode to enable photon detection. Conventional microchannel plates, made of glass fibers, ...

2025

Making from Breaking: Degradation Inversion Enables Vapor-Phase Synthesis of Halide Perovskites in Ambient Conditions

Christophe Ballif, Aïcha Hessler-Wyser, Mostafa Rabie Shlaly Bahr Othman, Kerem Artuk, Christian Michael Wolff, Austin George Kuba

Vapor phase deposition of formamidinium-rich perovskites is hampered by the decomposition of formamidine in the vapor phase. We use the reversibility of this reaction to establish a dynamic equilibrium that enables the vapor-phase synthesis of formamidiniu ...

American Chemical Society (ACS)2025

Three decades, three climates: environmental and material impacts on the long-term reliability of photovoltaic modules

Christophe Ballif, Hugo James André Quest

This study analyses 30+ years of PV performance in Switzerland, highlighting the reliability of early 90s modules. It examines outdoor system- and indoor module-level data, emphasising the importance of BOM and the benefits of lower temperatures. ...

Royal Society of Chemistry (RSC)2025

Co-annealing of PECVD boron emitters and poly-Si passivating contacts for leaner TOPCon solar cell fabrication

Christophe Ballif, Franz-Josef Haug, Julien Hurni, Ezgi Genç, Sofia Libraro

This study investigates the feasibility of a single-step annealing process for tunnel oxide passivating contact (TOPCon) solar cell fabrication to replace the conventional two-step approach. We present a novel method using a single thermal treatment to sim ...

2025

nc-SiC by PECVD for High-Temperature Passivating Contacts

Christophe Ballif, Franz-Josef Haug, Julien Hurni, Ezgi Genç

Institute of Electrical and Electronics Engineers (IEEE)2025

Embracing wind power in the solar PV-dominated Swiss landscape

Christophe Ballif, Nicolas Würsch, Alejandro Pena Bello, Marine Dominique Cauz

The Swiss energy transition, characterized by the nuclear phase-out, relies mainly on the integration of solar photovoltaic (PV), mostly because wind technology faces challenges in local public acceptance. This study aims to analyse Swiss PV and wind gener ...

Elsevier BV2025

Boron-emitter development for TOPCon c-Si solar cells based on plasma-deposited boron diffusion source and poly-Si(n) passivating contact

Christophe Ballif, Franz-Josef Haug, Julien Hurni, Ezgi Genç

The n-type TOPCon technology is currently the leading approach in the industry. Generally, it involves two high-temperature steps that can result in long cycle times and expensive processes. In this context, we propose a lean manufacturing process based on ...

2025

Characterization of Lightweight Polymeric Honeycomb Structures for Use as Backsides in Glass‐Free PV Modules

Christophe Ballif, Antonin Faes, Umang Bhupatrai Desai

In densely populated or mountainous countries where installation of large‐scale solar plants is challenging, photovoltaic (PV) modules in building applications offer a solution by transforming passive surfaces into energy‐generating systems. The need for f ...

Wiley2025

Novel Mechanically Robust and Environmentally Stable Light‐Weight Colored Photovoltaic Modules Based on Composite Polymer Backsheets

Christophe Ballif, Antonin Faes, Umang Bhupatrai Desai

Reliable and esthetically pleasing lightweight photovoltaic modules for building integration are expected to grow interest in the consumer market, especially for retrofitting older buildings and storehouses that are not structurally designed to withstand a ...

Wiley2025

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

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

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

Suppression of Stacking Faults for Stable Formamidinium-Rich Perovskite Absorbers

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

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

Detect, Decouple, Optimise: Insights into Solar Photovoltaics Faults and Performance Trends

Christophe Ballif, Hugo James André Quest

With the photovoltaics (PV) market reaching the terawatt scale, assessing the performance of PV systems accurately has become essential. Traditional approaches to fault detection and diagnosis (FDD) and performance loss rate (PLR) evaluation often operate ...

Wiley2025

Impact of Rapid Thermal Processing on Bulk Lifetime and Surface Recombination Velocity of Crystalline Silicon With Passivating Tunnel Oxide Contacts

Christophe Ballif, Franz-Josef Haug, Julien Hurni, Ezgi Genç, Sofia Libraro, Audrey Marie Isabelle Morisset

We investigate rapid thermal processing (RTP) as alternative to the prolonged thermal annealing process used to form tunnel-oxide passivating contacts for silicon solar cells. The thermal treatment is generally followed by hydrogenation to passivate defect ...

Wiley2025

Stress tolerance of lightweight glass-free PV modules for vehicle integration

Christophe Ballif, Aïcha Hessler-Wyser, Antonin Faes, Jacques Levrat, Matthieu Despeisse, Gianluca Cattaneo, Fahradin Mujovi, Umang Bhupatrai Desai

Electric vehicles (EVs) currently dominate the sales in the automotive market. A big leap in this market can be made by developing a photovoltaic product that can be integrated to an EV, as it can boost the driving range of the EV while reducing the chargi ...

Edp Sciences S A2024

Mapping the charging demand for electric vehicles in 2050 from mobility habits

Christophe Ballif, Nicolas Würsch, Alejandro Pena Bello, Noémie Alice Yvonne Ségolène Jeannin

This paper proposes a method to spatially model and compare charging needs on the European scale considering local disparities in population density, distance to city centres, car ownership and mobility habits. Mobility habits are modelled across Europe in ...

2024