Scalable two-terminal all-perovskite tandem solar modules with a 19.1% efficiency

Monolithic all-perovskite tandem photovoltaics promise low-cost, high-efficiency solar energy harvesting with thin-film advantages. This work reports laser-scribed all-perovskite tandem modules processed exclusively with scalable fabrication methods (blade coating and vacuum deposition), achieving power conversion efficiencies up to 19.1% on a 12.25 cm² aperture area with a 94.7% geometric fill factor and stable power output. Compared with spin-coated reference tandem cells (23.5% efficiency, 0.1 cm²), these prototypes demonstrate substantial advances in technological readiness. Electroluminescence imaging and laser-beam-induced current mapping show homogeneous current collection in both subcells over the entire module area, explaining the low losses (<5%) in open-circuit voltage and fill factor for the scalable modules.

Bahram Abdollahi Nejand, David B. Ritzer, Hang Hu, Fabian Schackmar, Somayeh Moghadamzadeh, Thomas Feeney, Roja Singh, Felix Laufer, Raphael Schmager, Raheleh Azmi, Milian Kaiser, Tobias Abzieher, Saba Gharibzadeh, Erik Ahlswede, Uli Lemmer, Bryce S. Richards, Ulrich W. Paetzold