Ultra-High Efficiency Perovskite-Perovskite Tandem Solar Cells

Next generation solar cells have the potential to achieve conversion efficiencies beyond the Shockley-Queisser (S-Q) limit while also significantly lowering production costs. To date, only multi-junction solar cells are able to achieve such high efficiencies. However, the current high-efficiency multi-junction cells require complex III-V-related epitaxial thin films and the use of an expensive single-crystal substrate, preventing low cost production of III-V multi-junction thin-film solar cells. In contrast to III-V films, polycrystalline thin-film solar cell technologies offer much lower production cost, but only moderate efficiencies. Fabricating highly efficient multi-junction polycrystalline thin-film solar cells remains a challenge.