Publications by Christophe Ballif

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Demand side management could be a very effective way to shift electric consumption of households to the maximum production hours of photovoltaic (PV) systems. A field study on more than 100 households were performed to evaluate the share of electric consum ...

We study the plasmonic and the non-plasmonic regimes of operation of a thin-film amorphous-silicon solar cell. By rigorous calculation, we discuss the impact of the cell geometry on the nature of its optical resonances.

Inverted perovskite solar cells face performance limitations due to non-radiative recombination at the perovskite surfaces in devices, including functional layers. Advanced characterization and density functional theory reveal that phosphonic acids passivate perovskite surface defects, while piperazinium chloride mitigates interface recombination by improving energy level alignment, introducing a field effect, and homogenizing the surface. Together, the quasi-Fermi level splitting of the perovskite is homog

We present our work on the combination of thin film silicon solar cells and a commercial window shading device (MicroShadeTM, PhotoSolar) into a novel, glass integrated photovoltaic product for building integration. The development of amorphous silicon sol ...

We report on the latest results of tandem micromorph (a-Si:H/μc-Si:H) silicon solar cells fabricated in commercial Oerlikon Solar KAI-S and KAI-M PECVD reactors. First developments of in-situ silicon oxide based intermediate reflector (SOIR) in KAI reactor ...

The present invention relates to a multiple-junction photoelectric device comprising, in sequence, a substrate (4), a first conducting layer (2), at least two elementary photoelectric devices (6, 10), at least one of said elementary photoelectric devices ( ...

Basic properties of plasma-deposited amorphous and microcrystalline layers are summarized. Limitations for solar cell performance, which are a result of these basic properties are pointed out. Efficiencies and other solar cell parameters obtained for the b ...

Wide-bandgap (WBG) perovskite absorbers play a pivotal role in enabling high-efficiency tandem solar cells; yet, their long-term operational stability remains a significant hurdle to commercialization.

A growth model for the low pressure chemical vapor deposition (LPCVD) of polycrystalline ZnO thin films is proposed. This model is based on experimental observations of the surface morphology and crystallographic orientations of the layers at different thi ...

Recent developments in photovoltaic technologies enable stimulating architectural integration into building façades and rooftops. Upcoming policies and a better coordination of all stakeholders will transform how we approach building-integrated photovoltai ...

In this abstract, we focus on reinforcing silicon heterojunction (SHJ) solar cells against degradation mechanisms induced by moisture and high-negative voltages. In order to verify that, the solar cells are encapsulated in a glass/backsheet (G/BS) module s ...

We presentanewtechniquetomeasurecomponentcurrent–voltage(I–V) curvesofindividual sub-cellsintegratedinamonolithicmulti-junctionsolarcell.Thisnewapproach,comparedtoall previouslyreportedones,iswellsuitedforthin-filmsiliconp–i–nstructureswheretheso-called shiftingapproximation,whichsupposesthatilluminationonlyshiftsthe I–V curve withoutchangingits shape, isnotvalid.Moreover,theproposedmethodisparticularlyresistanttoproblemsrelatedto electricalshunts.Theprincipleofthismethodliesincouplingthelevelofaselectiveli

An amorphous Si thin film with TiO2 encapsulation layer is demonstrated as a highly promising and stable photocathode for solar hydrogen production. With platinum as prototypical cocatalyst, a photocurrent onset potential of 0.93 V vs RHE and saturation ph ...

We conducted a long-term (>6500 h) in-situ PV module humidity monitoring experiment, where digital humidity sensors encapsulated in different encapsulants (EVA, TPO, POE and ionomer) were exposed to different humidity conditions in a climatic chamber. From ...

Dopant-free passivating contacts for photovoltaics have the potential to be deposited at low costs, while providing excellent surface passivation and low contact resistance. However, one pressing issue of dopant-free carrier selective contacts is their low ...

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 ...

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, ...

Combining the two technologies of tandem solar cells and bifacial solar cells has a great potential to maximize energy harvesting while minimizing material and surface usage. Mid-bandgap perovskites (1.50–1.60 eV) are important for fulfilling current match ...

We present two laser systems to monitor plasma conditions in a plasma-enhanced chemical vapor deposition chamber. The first optical system is a high-resolution quantum cascade laser-based infrared absorption spectrometer designed to measure the input silan ...

Elevated operating temperatures are expected in BIPV systems due to restricted or reduced rear-side ventilation, which impacts their performance and reliability. This work reports operating temperatures and diurnal (day-night) temperature variations of the ...

Christophe Ballif

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Demand Side Management for Enhanced Integration of Photovoltaics into Grid

Light-trapping in the near field: the case for plasmonic thin-film solar cells

60 cm2 perovskite-silicon tandem solar cells with an efficiency of 28.9% by homogeneous passivation

Thin film silicon solar cells in a semi-transparent micro-structured metal substrate configuration

Micromorph tandem solar cells grown at high rate with in-situ intermediate reflector in industrial KAI PECVD reactors

Multiple-junction photoelectric device and its production process

Technological status of plasma-deposited thin-film silicon photovoltaics

Unraveling bulk degradation mechanisms of wide-bandgap perovskite absorbers for tandem applications

LPCVD GROWTH OF ZNO FOR SOLAR CELL APPLICATIONS

Integrated thinking for photovoltaics in buildings

Development of Pid-resistant Silicon Heterojunction Solar Cells

Variable light biasing method to measure component I–V characteristics of multi-junction solar cells

Amorphous Si Thin Film Based Photocathodes with High Photovoltage for Efficient Hydrogen Production

In-situ Determination of Moisture Diffusion Properties of PV Module Encapsulants Using Digital Humidity Sensors

Degradation Mechanism and Stability Improvement of Dopant-Free ZnO/LiFx/Al Electron Nanocontacts in Silicon Heterojunction Solar Cells

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

Aryl-Acetylene Layered Hybrid Perovskites in Photovoltaics

Bifacial perovskite/silicon heterojunction tandem solar cells based on FAPbI3-based perovskite via hybrid evaporation-spin coating

Laser-based plasma diagnostics for PECVD of silicon thin films

Monitoring the Operating Temperatures of Modules in Open-Rack and Typical BIPV Configurations