@article{ZuWarbyStolterfohtetal.2021,
  author    = {Zu, Fengshuo and Warby, Jonathan and Stolterfoht, Martin and Li, Jinzhao and Shin, Dongguen and Unger, Eva and Koch, Norbert},
  title     = {Photoinduced energy-level realignment at interfaces between organic semiconductors and metal-halide perovskites},
  series = {Physical review letters},
  volume    = {127},
  journal   = {Physical review letters},
  number    = {24},
  publisher = {American Physical Society},
  address   = {College Park},
  issn      = {0031-9007},
  doi       = {10.1103/PhysRevLett.127.246401},
  pages     = {6},
  year      = {2021},
  abstract  = {In contrast to the common conception that the interfacial energy-level alignment is affixed once the interface is formed, we demonstrate that heterojunctions between organic semiconductors and metal-halide perovskites exhibit huge energy-level realignment during photoexcitation. Importantly, the photoinduced level shifts occur in the organic component, including the first molecular layer in direct contact with the perovskite. This is caused by charge-carrier accumulation within the organic semiconductor under illumination and the weak electronic coupling between the junction components.},
  language  = {en}
}
@article{LangKoehnenWarbyetal.2021,
  author    = {Lang, Felix and K{\"o}hnen, Eike and Warby, Jonathan and Xu, Ke and Grischek, Max and Wagner, Philipp and Neher, Dieter and Korte, Lars and Albrecht, Steve and Stolterfoht, Martin},
  title     = {Revealing fundamental efficiency limits of monolithic perovskite/silicon tandem photovoltaics through subcell characterization},
  series = {ACS Energy Letters},
  volume    = {6},
  journal   = {ACS Energy Letters},
  number    = {11},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2380-8195},
  doi       = {10.1021/acsenergylett.1c01783},
  pages     = {3982 -- 3991},
  year      = {2021},
  abstract  = {Perovskite/silicon tandem photovoltaics (PVs) promise to accelerate the decarbonization of our energy systems. Here, we present a thorough subcell diagnosis methodology to reveal deep insights into the practical efficiency limitations of state-of-the-art perovskite/silicon tandem PVs. Our subcell selective intensity-dependent photoluminescence (PL) and injection-dependent electroluminescence (EL) measurements allow independent assessment of pseudo-V-OC and power conversion efficiencies (PCEs) for both subcells. We reveal identical metrics from PL and EL, which implies well-aligned energy levels throughout the entire cell. Relatively large ideality factors and insufficient charge extraction, however, cause each a fill factor penalty of about 6\% (absolute). Using partial device stacks, we then identify significant losses in standard perovskite subcells due to bulk and interfacial recombination. Lastly, we present strategies to minimize these losses using triple halide (CsFAPb(IBrCI)(3)) based perovskites. Our results give helpful feedback for device development and lay the foundation toward advanced perovskite/silicon tandem PVs capable of exceeding 33\% PCE.},
  language  = {en}
}