Artuk, K.; Turkay, D.; Kuba, A.; Riemelmoser, S.; Steele, J. A.; Hurni, J.; Spitznagel, J.; Quest, H.; De Bastiani, M.; Zhao, J.; Diekmann, J.; Ongaro, C.; Othman, M.; Heydarian, M.; Fischer, O.; Lai, H.; Austin, J. S.; Zeiske, S.; López-Arteaga, R.; Liu, C.; Mensi, M. D.; Castro-Méndez, A.-F.; Li, M.; Gries, T. W.; Hill, S.; Saenz, F.; Champault, L.; Can, H. A.; Golobostanfard, M. R.; Desai, U.; Remondeau, P.; Solano, E.; Portale, G.; Faes, A.; Lang, F.; Musiienko, A.; Rolston, N.; Fu, F.; Schubert, M. C.; Schindler, F.; Chen, B.; Pasquarello, A.; Sargent, E. H.; Hessler-Wyser, A.; Jeangros, Q.; Ballif, C.; Wolff, C. M.: Triple-Junction Solar Cells with Improved Carrier and Photon Management. Nature early view (2026)
10.1038/s41586-026-10385-y
Abstract:
Perovskite-silicon triple-junction photovoltaics offer efficiency gains beyond dual-junction devices, but at the expense of added complexity. Here, we address two key bottlenecks in perovskite-silicon-based triple-junction solar cells: reduced open-circuit voltage in the wide-bandgap top-cell and limited photocurrent generation in the middle-cell. A non-volatile additive, 4-hydroxybenzylamine, regulates wide-bandgap perovskite crystallization and passivates defects, promoting oriented growth and suppressing non-radiative recombination. Together with improved energy-level alignment, this yields open-circuit voltages of up to 1.405?V and enhanced stability. To overcome the current limitations in the middle-cell, a three-step deposition strategy enables the formation of thick, low-bandgap perovskite absorbers while preserving microstructural integrity and enhancing electron extraction. In addition, low-refractive-index SiOx nanoparticles that accumulate in the front valleys of the textured silicon bottom-cell act as an optical middle-reflector, enhancing light absorption in the middle-cell. These advances are then combined in 1 cm² perovskite-perovskite-silicon devices, achieving a certified efficiency of 30.02%.