Search

Through the optimization of the perovskite precursor composition and interfaces to selective contacts, we achieved a p i n type perovskite solar cell PSC with a 22.3 power conversion efficiency PCE . This is a new performance record for a PSC with an absorber bandgap of 1.63 eV. We demonstrate that the high device performance originates from a synergy between 1 an improved perovskite absorber quality when introducing formamidinium chloride FACl as an additive in the triple cation Cs0.05FA0.79MA0.16PbBr0.51I2.49 Cs MAFA perovskite precursor ink, 2 an increased open circuit voltage, VOC, due to reduced recombination losses when using a lithium fluoride LiF interfacial buffer layer, and 3 high quality hole selective contacts with a self assembled monolayer SAM of [2 9H carbazol 9 yl ethyl]phosphonic acid 2PACz on ITO electrodes. While all devices exhibit a high performance after fabrication, as determined from current density voltage, J V, measurements, substantial differences in device performance become apparent when considering longer term stability data. A reduced long term stability of devices with the introduction of a LiF interlayer is compensated for by using FACl as an additive in the metal halide perovskite thin film deposition. Optimized devices maintained about 80 of the initial average PCE during maximum power point MPP tracking for gt;700 h. We scaled the optimized device architecture to larger areas and achieved fully laser patterned series interconnected mini modules with a PCE of 19.4 for a 2.2 cm2 active area. A robust device architecture and reproducible deposition methods are fundamental for high performance and stable large area single junction and tandem modules based on PSCs

Irradiation-induced phase segregation in mixed methylammonium halide perovskite samples such as methylammonium lead bromide-iodide, MAPb(I

Flat titanium dioxide films, to be used as the acceptor layer in bilayer hybrid solar cell devices, were prepared by spray-pyrolysis and by spin-casting. Both preparation methods resulted in anatase titania films with similar optical and electronic properties but considerably different film morphologies. Spray pyrolysis resulted in dense TiO₂ films grown onto and affected by the surface roughness of the underlying conducting glass substrates. The spin-casting preparation procedure resulted in nanoporous titania films. Hybrid solar cell devices with varying layer thickness of the small-molecule semiconducting dye TDCV-TPA were investigated. Devices built with spray-pyrolyzed titania substrates yielded conversion efficiencies up to 0.47%. Spin-cast titania substrates exhibited short circuits for thin dye layer thickness. For thicker dye layers the performance of these devices was up to 0.6% due to the higher interfacial area for charge separation of these nanoporous TiO₂ substrates.