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Surface textures are indispensable to minimize optical losses in perovskite-based solar cells. However, the solution-processing of perovskite layers is often not compatible with textured substrates, and little is known about the film growth thereon. This study aims to elucidate the growth process of perovskite layers from solution on textured substrates and to identify the texture features ensuring compatibility with perovskite solution-processing. Using nanoimprint-lithography we prepared three different periodically as well as randomly textured glass substrates for spin-coated perovskite solar cells, of which one was duplicated from a commercially available texture. During the perovskite crystallization process, a time-resolved in situ photoluminescence measurement was conducted. The photoluminescence signal was not found to substantially alter using textured substrates with texture heights around 500 nm. Optical absorptance spectroscopy and scanning electron microscopic imaging were applied to investigate the growth, crystal structure, and optical properties of solution-processed perovskite on top of different textures. We find that periodic textures with height around 500 nm enable homogeneous solution-processed perovskite layers with optimized optical performance. In contrast, texture heights of several micrometers lead to macroscopic holes in the perovskite film. The results of this study will help to find optimum optical textures for high-efficiency perovskite single-junction and perovskite-silicon tandem solar cells.

SnO2 is a widely used electron‐transporting layer (ETL) in perovskite solar cells. Despite the high compatibility with the perovskite absorber layers, the presence of traps at the perovskite|SnO2 interface results in performance losses; hence, their modification to improve the performance and stability of perovskite solar cells (PSCs) is therefore important. Herein, the SnO2 ETL is enhanced by incorporating a bifunctional aromatic amino fluorine molecule into the SnO2 precursor solution. The fluorine molecule is found to partially substitute the Sn and alter the energy levels while the aniline group aids in regulating the nucleation/growth rate of the perovskite crystalline films. Herein, a hole transporting material‐free carbon‐based PSCs (CPSCs) is fabricated. It is found that perovskite absorber layers deposited on these modified SnO2 hybrid layers have higher optoelectronic quality, resulting in enhanced photovoltaic performance, device stability, and reduced hysteresis in CPSCs. Devices made with the modified hybrid SnO2 layers exhibit power conversion efficiencies of 15.6% significantly better than unmodified SnO2 with 13.5%. CPSCs with these modified SnO2 films also exhibit remarkable retention of 88.7% of their initial PCE for a shelf‐life period (ISOS‐D1I) exceeding 1200 h. [ABSTRACT FROM AUTHOR]

Thin‐film perovskite light‐emitting diodes have gained increasing attention in the last 6 years. With the possibility to process the emitting layer from solution, the way for 1D morphology of the semiconductor for flexible devices is paved. Herein, for the first time single‐step fabrication of CsPbBr3@PVP nanofibers in a customized electrospinning process performed under ambient conditions from a water‐based precursor solution is reported. The water‐based approach allows the incorporation of a conductive polymer into the compound fiber by blending the perovskite precursor ink with commercially available PEDOT:PSS dispersion. The results demonstrate electrospun fiber mats which are stable at ambient conditions for at least 5 months and can be utilized in electroluminescence devices. Photoluminescence studies on the perovskite fibers reveal a blueshift of the emission peak compared to thin films possibly due to the generation of nanocrystals of ≈12 nm by in situ nanocrystal pinning as confirmed by transmission electron microscopy. A proof‐of‐concept electrically pumped light‐emitting device is built with the obtained fiber mat. The perovskite nanofibers offer promising applications in flexible and stretchable optoelectronics. [ABSTRACT FROM AUTHOR]

To accelerate the materials discovery and development process for a sustainable technology advancement it is imperative to explore and develop combined high-throughput material synthesis and analysis workflows. In this work, we investigate a method of combinatorial inkjet-printing to tune the composition of the inorganic cesium lead mixed halide perovskite solid solution, CsPb(BrxI1−x)3. The compositional variation is achieved by simultaneous printing of different precursor inks with multiple printheads and controlled by varying the number of droplets printed by each printhead throughout the sample. The droplet placement is optimised through an algorithm that allows maximum mixing of the combined inks. The local compositional homogeneity of thin-film samples was investigated as a function of the printing resolution by micrometer-resolution X-ray fluorescence and synchrotron-based grazing-incidence wide-angle X-ray scattering. We show that a combinatorial library of ten compositions between CsPbI3 and CsPbBr2I, printed using the developed algorithm, is locally homogeneous for the optimised printing parameters. An implementation of the algorithm in the high-level programming language Python is provided for easy use in other systems. [ABSTRACT FROM AUTHOR]

Metal halide perovskite solar cells (PSCs) have gained significant attention in thin-film photovoltaic research for their high power conversion efficiency (PCE) and facile fabrication processes. This study presents the use of inkjet printing to fabricate thin films of combinatorial mixed formamidinium tin-lead perovskites and evaluates their layer quality and device performance. Our findings demonstrate that incorporating Pb up to 50% into FASnI 3 films enhances lattice stability. The investigation focused on optimizing the composition ratio for improved photovoltaic performance with FASn 0.5 Pb 0.5 I 3 -based PSCs achieving the highest PCE of 10.26%. Additionally, these cells exhibited an absorption spectrum extending beyond 1000 nm, corresponding to a 1.25 eV bandgap. The results suggest that inkjet printing can effectively enhance the efficiency of tin-lead-based PSCs, supporting scalability in device manufacturing.