Person

Stefaan De Wolf

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Related publications (95)

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

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

Photocurrent Spectroscopy of Perovskite Layers and Solar Cells: A Sensitive Probe of Material Degradation

Christophe Ballif, Stefaan De Wolf, Björn Niesen, Jérémie Werner, Jakub Holovsky, Philipp Friedrich Hermann Löper, Martin Ledinsky, Martin Müller

Optical absorptance spectroscopy of polycrystalline CH3NH3PbI3 films usually indicates the presence of a PbI2 phase, either as a preparation residue or due to film degradation, but gives no insight on how this may affect electrical properties. Here, we app ...

Amer Chemical Soc2017

Simple processing of back-contacted silicon heterojunction solar cells using selective-area crystalline growth

Christophe Ballif, Quentin Thomas Jeangros, Antoine Descoeudres, Gabriel Christmann, Bertrand Yves Paul Paviet-Salomon, Matthieu Despeisse, Stefaan De Wolf, Sylvain Nicolay, Loris Barraud, Jan Haschke, Johannes Peter Seif, Andrea Tomasi

For crystalline-silicon solar cells, voltages close to the theoretical limit are nowadays readily achievable when using passivating contacts. Conversely, maximal current generation requires the integration of the electron and hole contacts at the back of t ...

Nature Publishing Group2017

Optical Evaluation of the Rear Contacts of Crystalline Silicon Solar Cells by Coupled Electromagnetic and Statistical Ray-Optics Modeling

Christophe Ballif, Franz-Josef Haug, Stefaan De Wolf, Monica Morales Masis, Ali Dabirian

High-efficiency crystalline silicon (c-Si) solar cells increasingly feature sophisticated electron and hole contacts aimed at minimizing electronic losses. At the rear of photovoltaic devices, such contacts-usually consisting of stacks of functional layers ...

Ieee-Inst Electrical Electronics Engineers Inc2017

Increasing the efficiency of silicon heterojunction solar cells and modules by light soaking

Christophe Ballif, Franz-Josef Haug, Antoine Descoeudres, Jacques Levrat, Matthieu Despeisse, Stefaan De Wolf, Eiji Kobayashi

Silicon heterojunction solar cells use crystalline silicon (c-Si) wafers as optical absorbers and employ bilayers of doped/intrinsic hydrogenated amorphous silicon (a-Si:H) to form passivating contacts. Recently, we demonstrated that such solar cells incre ...

Elsevier Science Bv2017

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

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

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

The impact of silicon solar cell architecture and cell interconnection on energy yield in hot & sunny climates

Christophe Ballif, Jacques Levrat, Matthieu Despeisse, Stefaan De Wolf, Jan Haschke, Johannes Peter Seif, Jean Cattin, Yannick Samuel Riesen, Andrea Tomasi, Brahim Aissa

Extensive knowledge of the dependence of solar cell and module performance on temperature and irradiance is essential for their optimal application in the field. Here we study such dependencies in the most common high-efficiency silicon solar cell architec ...

Royal Soc Chemistry2017

Impact of organic overlayers on a-Si:H/c-Si surface potential

Christophe Ballif, Stefaan De Wolf, Björn Niesen, Johannes Peter Seif, Andrea Tomasi

Bilayers of intrinsic and doped hydrogenated amorphous silicon, deposited on crystalline silicon (c-Si) surfaces, simultaneously provide contact passivation and carrier collection in silicon heterojunction solar cells. Recently, we have shown that the pres ...

American Institute of Physics2017

Field-effect passivation on silicon nanowire solar cells (vol 8, pg 673, 2015)

Anna Fontcuberta i Morral, Stefaan De Wolf, Bénédicte Demaurex, Anna Dalmau Mallorquí, Amirreza Kiani

Surface recombination represents a handicap for high-efficiency solar cells. Surface recombination represents a handicap for high-efficiency solar cells. This is especially important for nanowire array solar cells, where the surface-to-volume ratio is grea ...

Tsinghua Univ Press2016

Asymmetric band offsets in silicon heterojunction solar cells: Impact on device performance

Christophe Ballif, Antoine Descoeudres, Stefaan De Wolf, Loris Barraud, Johannes Peter Seif, Ugur Deneb Menda

Amorphous/crystalline silicon interfaces feature considerably larger valence than conduction band offsets. In this article, we analyze the impact of such band offset asymmetry on the performance of silicon heterojunction solar cells. To this end, we use si ...

Amer Inst Physics2016

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