Perovskite/Silicon Monolithic Tandem Based on a P-type High-temperature Tolerant Silicon Bottom Cell

Florent Sahli^a, Gizem Nogay^b, Jérémie Werner^a^,^c, Fan Fu^a, Arnaud Walter^b, Saeid Rafizadeh^b, Vincent Paratte^a, Raphäel Monnard^a, Brett A. Kamino^b, Peter Fiala^a, Terry Chien-Jen Yang^a, Matthias Bräuninger^a, Ricardo A. Z. Razera^a, Matthieu Despeisse^b, Sylvain Nicolay^b, Mathieu Boccard^a, Andrea Ingenito^a, Quentin Jeangros^a, Christophe Ballif^a^,^b

^aÉcole Polytechnique Fédérale de Lausanne (EPFL), Institute of Microengineering (IMT), Photovoltaics and Thin-Film Electronics Laboratory (PV-Lab), CH, Rue de la Maladière, 71, Neuchâtel, Switzerland

^bCSEM, PV-Center, Jaquet-Droz 1, 2002 Neuchâtel, Switzerland.

^cǂ now at University of Colorado Boulder, Colorado, USA., United States

International Conference on Hybrid and Organic Photovoltaics
Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV19)

Roma, Italy, 2020 May 12th - 14th

Organizers: Prashant Kamat, Filippo De Angelis and Aldo Di Carlo

Oral, Florent Sahli, presentation 164
Publication date: 6th February 2020

Increasing the power output per unit area is the most promising way to further decrease the levelized cost of electricity (LCOE) of crystalline silicon (c-Si) photovoltaics. In this regard, adding a wide-bandgap top cell to c-Si can reduce thermalization losses and enables the cell to surpass the theoretical efficiency limit of single-junctions. Organic-inorganic perovskite solar cells have been identified as promising partners for silicon solar cells due to their high power conversion efficiency at the single-junction level, sharp absorption edge, and potentially low fabrication costs. Because of these attributes, perovskite/c-Si tandems have the potential to achieve efficiencies >30% at a competitive LCOE, with a current record efficiency of 28%. Until now, all published perovskite/c-Si devices with efficiencies over 25% have featured an n-type silicon heterojunction (SHJ) bottom cell.1-4 While this type of cell can reach high efficiencies, the low thermal stability of the passivating and selective amorphous silicon layers of SHJ cells limit the perovskite top cell processing to temperatures below 250°C, which limits the choice of charge-selective contact materials. In contrast to mainstream contacting schemes, the low processing temperature of SHJs does not trigger any improvement of the wafer through impurity gettering and/or thermal donor deactivation, preventing the use of low-quality p-type wafers routinely used in the industry. Here we demonstrate the first tandem solar cell featuring a p-type bottom silicon cell based on passivating contacts formed at high temperatures,⁵ achieving a steady-state efficiency of 25.1%. This value is on par with our record tandems made with n-type SHJs. The c-Si bottom cell fabrication reported here is compatible with the high-temperature emitter diffusion processes used today in the c-Si PV industry. In addition, the high-temperature tolerance of the bottom silicon cell allows using charge-selective contacts formed at high temperatures such as m-TiO_x, c-TiO_x, NiO_x, SnO_x for an improved top cell efficiency.

References:

[1] Sahli, F. et al. Fully textured monolithic perovskite/silicon tandem solar cells with 25.2% power conversion efficiency. Nat. Mater. (2018).

[2] Bush, K. A. et al. Minimizing Current and Voltage Losses to Reach 25%-Efficient Monolithic Two-Terminal Perovskite-Silicon Tandem Solar Cells. ACS Energy Lett. acsenergylett.8b01201 (2018).

[3] Chen, B. et al. Grain Engineering for Perovskite/Silicon Monolithic Tandem Solar Cells with Efficiency of 25.4%. Joule 1–14 (2018).

[4] Jošt, M. et al. Textured interfaces in monolithic perovskite/silicon tandem solar cells: Advanced light management for improved efficiency and energy yield. Energy Environ. Sci. (2019).

[5] Nogay, G. et al. Crystalline Silicon Solar Cells With Coannealed Electron- and Hole-Selective SiC x Passivating Contacts. IEEE J. PhotovoltaicsJournal Photovolatics 1–8 (2018).

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.