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Pentacene thin-films OFETs show increased conductance and mobility after exposure to maleic anhydride which shifts the mean energy in the grain boundaryviaan applied dipole. 

Perovskite optoelectronics are regarded as a disruptive technology, but their susceptibility to environmental degradation and reliance on toxic solvents in traditional processing methods pose significant challenges to their practical implementation. Herein, methylammonium lead iodide (MAPbI3) perovskite films processed via a solvent free laser printing technique, that exhibit exceptional stability, are reported. These films withstand extreme conditions, including high doses of X-ray radiation exceeding 200 Gy, blue laser illumination, 90% relative humidity, and thermal stress up to 80 °C for over 300 min in air. We demonstrate that laser-printed films maintain their structural integrity and optoelectronic properties even after prolonged exposure to these stressors, significantly surpassing the stability of conventionally processed films. The enhanced stability is attributed to the unique film formation mechanism and resulting defect-tolerant microstructure. These results underscore the potential of laser printing as a scalable, safe, and sustainable manufacturing route for producing stable perovskite-based devices with potential applications in diverse fields, ranging from renewable energy to large-area electronics and space exploration. 

Abstract Metal halide perovskites have ascended as a remarkable class of materials in recent years, demonstrating exceptional promise for application in various electronic and optoelectronic devices. The vast majority of research on these materials focuses on their processing from solution, which is relatively easily executed in laboratory settings, but its scalability for industrial mass production remains a significant hurdle. Furthermore, its reliance on highly toxic solvents imposes limitations with respect to large‐area fabrication and have a negative environmental impact. This review comprehensively explores the current status of solvent‐free fabrication methods for metal halide perovskites, outlines the current challenges and opportunities, and provides a critical assessment of the technological readiness and future research directions. The development of robust and scalable solvent‐free fabrication methodologies is essential to realizing the full potential of metal halide perovskites. We hope that this review will serve as a catalyst, inspiring and guiding researchers to explore new strategies for the solvent‐free deposition of these remarkable materials, thereby expediting their integration into technological applications. 

Abstract The electronic effects of structural defects introduced through chemical doping are challenging to characterize in organic semiconductors, especially when measured in thin film devices where the performance is sensitive to structural heterogeneity. Here, a simple approach is presented to probe the roles of indirect and direct electronic coupling on charge transport in a series of compositionally varied charge‐transfer single crystals. In this system, carbazole (CBZ) is controllably substituted withN‐methylcarbazole (NMCBZ) in the cocrystal formed between CBZ and 1,3,4,5,7,8‐hexafluoro‐11,11,12,12‐tetracyano‐2,6‐naphthoquinodimethane (F₆TNAP), producing a series of single crystals with compositions that range between 0 – 50% CBZ replacement and preserve the structure type of the parent cocrystal. Gas‐phase electronic structure calculations predict that substitutional replacement of CBZ with NMCBZ introduces two competing effects: (i) strengthening of indirect coupling by increasing the average degree of charge transfer and (ii) weakening of direct exchange by increasing the distance between adjacent charge‐transfer π‐stacks. Charge transport measurements reveal an initial decrease in the mobility upon substitution of CBZ with NMCBZ, rationalized by a combination of hole‐trapping and weakened direct coupling with increasing NMCBZ content. Critically, these results demonstrate the potential for solid solutions to offer insight into charge transport mechanisms and their chemical tunability in molecular electronic materials.