Charge Extraction in Flexible Perovskite Solar Cell Architectures for Indoor Applications – with up to 31% Efficiency
Cristina Teixeira, Pierpaolo Spinelli, Luigi Angelo Castriotta, David Müller, Senol Öz, Luísa Andrade, Adélio Mendes, Aldo Di Carlo, Uli Würfel, Konrad Wojciechowski, Dávid Forgács
Abstract
Abstract Perovskite Solar Cells (PSCs) are well known for their high efficiencies under 1 sun (AM1.5G), however, PSC can also generate power by harvesting the low‐light available indoors. Here, three flexible PSC architectures are presented for indoor applications: with a metal electrode aiming for high efficiency; carbon electrode aiming for high stability and compatibility with large‐scale production; and hole transport material (HTM)‐free carbon for simplifying the fabrication process. A maximum efficiency of 30.9% (30.0%) under 1000 lux (200 lux) is obtained for a PSC with gold electrode. A maximum efficiency of 25.4% (24.7%) and 23.1% (22.3%) is obtained for the carbon devices with and without HTM, respectively, under 1000 lux (200 lux). To the best of the author's knowledge, the efficiency values presented here for a device with a carbon‐based electrode, with and without HTM, are the record values for a flexible PSC at indoor light conditions. Furthermore, the HTM‐free carbon device kept 84% of its initial efficiency after 1000 h at MPPT and lost virtually no performance after 1000 h at 85 °C. Also, non‐encapsulated devices of all configurations withstood 1600 h in air with a maximum loss in efficiency of 6%.