Fully textured perovskite-silicon tandem solar cells are revolutionizing the solar industry by offering higher efficiency and compatibility with existing silicon production lines. However, for these advanced cells to reach commercial markets, scalable manufacturing methods are essential, not just for the perovskite layers but for all functional components.
One crucial layer is the hole transport layer (HTL), which ensures efficient charge carrier transfer and minimizes energy losses. Self-assembled monolayers (SAMs) are commonly used as HTLs due to their ability to form smooth, efficient interfaces with the perovskite layer. However, the traditional spin-coating method for applying SAMs poses challenges on large, textured silicon surfaces, often resulting in uneven layers that compromise performance.
To address this, we investigated thermal evaporation as an alternative HTL deposition technique. Thermal evaporation provides uniform layer application on textured surfaces, making it a promising solution for large-scale production. Our research revealed that the thickness of thermally evaporated HTLs significantly affects two key performance metrics: open-circuit voltage (VOC) and fill factor (FF). By optimizing HTL thickness, we achieved remarkable efficiencies: ~30% for 1 cm² cells and ~26% for 4 cm² devices. This breakthrough demonstrates that thermal evaporation is a scalable and effective method for producing high-performance tandem solar cells, paving the way for affordable and accessible solar technologies.
https://pubs.rsc.org/en/content/articlelanding/2024/ee/d4ee03899a
The Borchert Lab 