SKM 2023 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 6: Perovskite and photovoltaics I (joint session HL/CPP)
CPP 6.1: Talk
Monday, March 27, 2023, 09:30–09:45, JAN 0027
Bandgap engineering of two-step processed perovskite top cells for application in perovskite-based tandem photovoltaics — •Ronja Pappenberger1,2, Alexander Diercks2, Ahmed Farag1,2, Paul Faßl1,2, and Ulrich W. Paetzold1,2 — 1Institut für Mikrostrukturtechnologie, KIT, Germany — 2Lichttechnisches Institut, KIT, Germany
Tandem solar cells offer a promising concept of raising the efficiency of silicon solar cells above the theoretical limit of 29%. In this context, silicon is supplemented by a wide-bandgap perovskite top solar cell to make better use of the solar spectrum. Perovskite solar cells come into play given their favorable optoelectronic quality and tunable bandgap. Textured-front perovskite silicon tandem solar cells currently promise the highest energy yield for modules in the field. To avoid shunting, ensure high efficiency and economic production of the perovskite on the µm-sized pyramids, a conformal growth of the perovskite layer as well as a sufficient layer thickness are necessary. A two-step method - containing a separate deposition of the PbI2 and the organic cations - enables high film quality, flexibility in choice of component/solution and the possibility of upscaling. Here, we investigate different strategies of increasing the bandgap of the perovskite. Thereby the location of the added bromine - cation solution and/or PbI2 solution - is critical. With our approach, the device performance - PCE of 17.2%, FF of 76% and Voc of 1.156 V (Eg ≈ 1.64 eV) - and film quality can be maintained. Furthermore, the effect of an increasing bandgap in combination with planar/textured silicon bottom cells is studied.