20.500.12556/RUL-178226 Tailoring nanoscale interfaces for perovskite–perovskite–silicon triple-junction solar cells Triple‐junction solar cells theoretically outperform their double-junction and single‐junction counterparts in power conversion efficiency, yet practical perovskite–perovskite–silicon devices have fallen short of both theoretical limits and commercial targets. To address surface defects in the top perovskite junction, we introduce a piperazine-1,4-diium chloride treatment, which replaces less stable lithium fluoride. For interfacing the top and middle perovskite junctions, we optimize the size of gold nanoparticles deposited on atomic layer-deposited tin oxide for best ohmic contacting with minimal optical losses. Applying these strategies, our champion 1-cm2 triple‐junction cell achieved a third party-verified reverse‐scan power conversion efficiency of 27.06% with an open circuit voltage of 3.16 V. Scaling up to 16 cm2 , the device produced a certified steady‐state power conversion efficiency of 23.3%. Device longevity also improved by eliminating methylammonium and incorporating rubidium into the perovskite bulk alongside the piperazine-1,4-diium chloride surface layer. An encapsulated 1-cm2 cell retained 95% of its initial efficiency after 407 h at maximum power point and passed the IEC 61215 thermal cycling test. These results represent advancements towards efficient and stable perovskite–perovskite–silicon triple-junction solar cells. photovoltaics solar cell perovskite interface analysis fotovoltaika sončna celica perovskit analiza vmesnih spojev true false true Angleški jezik Slovenski jezik Članek v reviji 2026-01-21 14:31:30 2026-01-21 14:31:33 2026-01-22 04:36:27 0000-00-00 00:00:00 2025 0 0 Str. 1648-1655 Vol. 20 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.383.51:549.641 1748-3395 10.1038/s41565-025-02015-x 252946947 s41565-025-02015-x_(1).pdf s41565-025-02015-x_(1).pdf 1 0702F5E1A4838B41223DA556B2861033 1c0ff5f2e406606861ad4274b27c4bdbd03097ac49fbf11358442fddce2a4810 bda3871b-f6cd-11f0-bf92-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=225853 https://www.nature.com/articles/s41565-025-02015-x 1 72f7ad82-f6cd-11f0-bf92-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=225852 Fakulteta za elektrotehniko 0 0 0