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Sputtered nickel oxide (NiOx) is an attractive hole‐transport layer for efficient, stable, and large‐area p‐i‐n metal‐halide perovskite solar cells (PSCs). However, surface traps and undesirable chemical reactions at the NiOx/perovskite interface are limiting the performance of NiOx‐based PSCs. To address these issues simultaneously, an efficient NiOx/perovskite interface passivation strategy by using an organometallic dye molecule (N719) is reported. This molecule concurrently passivates NiOx and perovskite surface traps, and facilitates charge transport. Consequently, the power conversion efficiency (PCE) of single‐junction p‐i‐n PSCs increases from 17.3% to 20.4% (the highest reported value for sputtered‐NiOx based PSCs). Notably, the N719 molecule self‐anchors and conformally covers NiOx films deposited on complex surfaces. This enables highly efficient textured monolithic p‐i‐n perovskite/silicon tandem solar cells, reaching PCEs up to 26.2% (23.5% without dye passivation) with a high processing yield. The N719 layer also forms a barrier that prevents undesirable chemical reactions at the NiOx/perovskite interface, significantly improving device stability. These findings provide critical insights for improved passivation of the NiOx/perovskite interface, and the fabrication of highly efficient, robust, and large‐area perovskite‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Slot‐die (SD) coating is used to fabricate fully solution processed organic solar cells (OSCs) based on a blend of high performance donor polymer (PTB7‐Th) and a non‐fullerene acceptor (IEICO‐4F) for stable devices over extended periods of operation. The optimization of a sequential deposition process of transport and active layers, under ambient conditions, enable high efficiency slot‐die coated solar cells with remarkable power conversion efficiencies (PCE) > 11.0% to bridge the gap between lab‐to‐fab. Fully slot‐die coated inverted OSCs are demonstrated with efficiencies reaching 11% along with 1 cm2 devices, proving the scalability and reproducibility of the proposed technique. Further, replacing the evaporated Ag electrode with solution processed Ag nanowire (AgNW) electrodes shows the highest light utilization efficiency of 5.26% for semi‐transparent OSC with a PCE of 9.07% and average visible transmission of 58%. [ABSTRACT FROM AUTHOR]

New polymer donors and nonfullerene acceptors have elevated the performance and stability of solar cells to higher grounds. To achieve their full potential, they require their adaptation to scalable and cost‐effective solution manufacturing techniques for large area deposition. Likewise, formulating scalable solution‐based transport layer inks that are compatible with the photoactive layer is imperative. This manuscript reports the full integration of solution‐based transport layers and electrode alongside a PTB7‐Th:IEICO‐4F bulk heterojunction in inverted architecture through inkjet‐printing, resulting in power conversion efficiencies up to 12.4% opaque devices and 9.5% semitransparent devices with average visible transmittance values of 50.1%, including hole transport layer. The wetting envelope of the highly‐hydrophobic photoactive layer alongside the surface energy of candidate solutions and solvents allows the formulation of thick transport layer inks that are compatible with the drop‐on‐demand inkjet‐printing process and yield uniform and homogenous films. Moreover, the surface energy components of the donor and acceptor serves as a fingerprint to assess the vertical stratification of the photoactive layer with the inclusion of different solvents. This methodology addresses a scale‐up bottleneck of solution‐based transport layers for high‐efficiency organic cells, enabling its adaptation to high‐throughput techniques including slot‐die and roll‐to‐roll coating. [ABSTRACT FROM AUTHOR]

Ultra‐lightweight solar cells have attracted enormous attention due to their ultra‐conformability, flexibility, and compatibility with applications including electronic skin or miniaturized electronics for biological applications. With the latest advancements in printing technologies, printing ultrathin electronics is becoming now a reality. This work offers an easy path to fabricate indium tin oxide (ITO)‐free ultra‐lightweight organic solar cells through inkjet‐printing while preserving high efficiencies. A method consisting of the modification of a poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) ink with a methoxysilane‐based cross‐linker (3‐glycidyloxypropyl)trimethoxysilane (GOPS)) is presented to chemically modify the structure of the electrode layer. Combined with plasma and solvent post‐treatments, this approach prevents shunts and ensures precise patterning of solar cells. By using poly(3‐hexylthiophene) along rhodanine‐benzothiadiazole‐coupled indacenodithiophene (P3HT:O‐IDTBR), the power conversion efficiency (PCE) of the fully printed solar cells is boosted up to 4.73% and fill factors approaching 65%. All inkjet‐printed ultrathin solar cells on a 1.7 µm thick biocompatible parylene substrate are fabricated with PCE reaching up to 3.6% and high power‐per‐weight values of 6.3 W g−1. After encapsulation, the cells retain their performance after being exposed for 6 h to aqueous environments such as water, seawater, or phosphate buffered saline, paving the way for their integration in more complex circuits for biological systems. [ABSTRACT FROM AUTHOR]

High fill factors have only recently become commonplace in nonfullerene‐based organic solar cells, with the balance of charge carrier mobilities often cited as the contributing factor. Here an end‐group modification to a commonly used nonfullerene acceptor (O‐IDTBR) is reported, in which the rhodanine end groups are replaced with dicyano moieties, resulting in the acceptor O‐IDTBCN. This new acceptor affords significant improvement in the fill factor (73%) and photocurrent (19.8 mA cm−2) in organic solar cells with the low bandgap polymer PTB7‐Th. A narrowing of the bandgap, as a result of greater push–pull hybridization, allows complementary absorption to the donor and thus improved photon harvesting. Additionally, the measurement of charge carrier mobilities and lifetimes in both systems reveal that the PTB7‐Th:O‐IDTBCN blend possesses more balanced charge carrier mobilities, and longer lifetimes. Morphology studies reveal a slightly greater degree of molecular mixing of the O‐IDTBCN when blended with PTB7‐Th, despite the greater and more balanced charge carrier mobilities in this blend. [ABSTRACT FROM AUTHOR]

The high crystallinity and ability to harvest near‐infrared photons make diketopyrrolopyrrole (DPP)‐based polymers one of the most promising donors for high performing organic solar cells (OSCs). However, DPP‐based OSC devices still suffer from the trade‐off between energetic loss (Eloss) and maximum external quantum efficiency (EQEmax), which significantly hinders their potential. Thus far, the replacement of fullerenes with small molecule acceptors did not wisdom the performance development of DPP‐donor‐based solar cells due to severe charge recombination issues. In this work, efficient DPP‐based solar cells are reported using low bandgap fused ring electron acceptor, IEICO‐4F. PBDTT‐DPP:IEICO‐4F OSC devices deliver a champion power conversion efficiency of 9.66% with successful interface engineering along with low Eloss of 0.57 eV and a high EQEmax (>70%). [ABSTRACT FROM AUTHOR]