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The rapid rise in single-junction perovskite solar cell (PSC) efficiencies, tunable bandgap and low-cost solution processability make PSCs an attractive candidate for tandems with Si bottom cells. However, the challenge is to fabricate a high-performance semitransparent perovskite top cell in combination with an appropriate silicon bottom cell with high response to long wavelength photons that are filtered through the perovskite top cell. Currently, semitransparent perovskite cells show much lower performance compared to their opaque counterparts while high-performance silicon bottom cells, such as heterojunction with intrinsic thin layer (HIT) and interdigitated back contact (IBC), maybe too expensive to meet the cost and efficiency targets for commercial viability. Here, we demonstrate a 26.7% perovskite-Si four terminal (4T) tandem cell comprising a highly efficient 17.8% CsFAMAPbIBr semitransparent, 1.63-eV bandgap perovskite top cell and a ≥ 22% efficiency n-type Si bottom cell fabricated with a conventional boron diffused emitter on the front and carrier selective n+ poly-Si/SiOx passivated contact on the rear. This is among the highest efficiency perovskite/Si 4T tandems published to-date and represents the first demonstration of the use of the high temperature-resistant single side n-TOPCon Si cell in a 4T configuration.
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This content will become publicly available on June 1, 2025
Exploring the Feasibility and Performance of Perovskite/Antimony Selenide Four-Terminal Tandem Solar Cells
The tandem solar cell presents a potential solution to surpass the Shockley–Queisser limit observed in single-junction solar cells. However, creating a tandem device that is both cost-effective and highly efficient poses a significant challenge. In this study, we present proof of concept for a four-terminal (4T) tandem solar cell utilizing a wide bandgap (1.6–1.8 eV) perovskite top cell and a narrow bandgap (1.2 eV) antimony selenide (Sb2Se3) bottom cell. Using a one-dimensional (1D) solar cell capacitance simulator (SCAPS), our calculations indicate the feasibility of this architecture, projecting a simulated device performance of 23% for the perovskite/Sb2Se3 4T tandem device. To validate this, we fabricated two wide bandgap semitransparent perovskite cells with bandgaps of 1.6 eV and 1.77 eV, respectively. These were then mechanically stacked with a narrow bandgap antimony selenide (1.2 eV) to create a tandem structure, resulting in experimental efficiencies exceeding 15%. The obtained results demonstrate promising device performance, showcasing the potential of combining perovskite top cells with the emerging, earth-abundant antimony selenide thin film solar technology to enhance overall device efficiency.
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- PAR ID:
- 10509822
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Solar
- Volume:
- 4
- Issue:
- 2
- ISSN:
- 2673-9941
- Page Range / eLocation ID:
- 222 to 231
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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