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Meniscus‐guided coating (MGC) is a promising method that offers predictable fabrication of highly crystalline thin films. For the integration of molecular semiconductors into large‐area electronic devices with high efficiency and reliability, homogeneous and highly ordered film morphologies are required. The solution processing of such defect‐free film structures requires comprehensive understanding of the complex relationship between molecular crystallization, fluid dynamics, and meniscus shape. In this work, the role of the meniscus shape on fluid dynamics in the coating bead and the crystallization process of the low molecular weight semiconductor 6,13‐bis(triisopropylsilylethynyl)pentacene (TIPS‐pentacene) during zone‐casting is systematically investigated. Depending on meniscus shape and coating velocity, four morphological subregimes are found: stick‐slip morphology, unidirectional homogenous crystal stripes, spherulitic morphology, and directional branched morphology; of which the second exhibits the highest crystallinity with a reduced trap density in the thin film, resulting in improved saturation and effective mobilities in field‐effect transistors (FET). Numerical simulation of fluid dynamics explains the observed morphological trends, which are correlated with the electrical behavior of the devices. This work provides a fundamental basis for upscaling MGC methods for the application of functional thin films. [ABSTRACT FROM AUTHOR]

The periphery of the microdroplets exhibits unusual physical properties that are not observed in bulk solutions. This work demonstrates in water microdroplets OH− can spontaneously donate electrons for CO2 hydrogenation to formic acid (FA), which may be driven by a strong electric field at or near the interfaces of water microdroplets. Surprisingly, Cu ions in microdroplets contribute to a 4000 times increase in output of FA. Control experiments show that in water microdroplets, electrons can be deposited by valence alternation of Cu to form Cu speciation, which can promote formate conversion. The authors show for the first time, without using any additives, under ambient conditions water microdroplets can capture CO2 and reduce CO2 to formate, which implies that water microdroplets may have provided a reactor for abiotic reduction reactions in the prebiotic era, thereby synthesizing organic molecules from atmospheric CO2 with a nonenzymatic production power before the advent of biotic reducing types of machinery. [ABSTRACT FROM AUTHOR]

A significant enhancement in ultraviolet (UV)‐durable indium tin oxide (ITO)‐free flexible nonfullerene organic solar cells (OSCs) is demonstrated using a hybrid nanostructured flexible transparent electrode (FTE), comprising a mixture of 0D silver nanoparticles, 1D Ag nanowires, and 2D exfoliated graphene sheets. The FTE exhibits high optical transparency and electric conductivity, good air stability, and full solution fabrication capability at a low processing temperature. An average power convention efficiency of 8.15% is obtained for the flexible nonfullerene OSCs, based on the blend of poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene))‐alt‐(5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c:4′,5′‐c′]dithiophene‐4,8‐dione)] (PBDB‐T): 3,9‐ bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′] dithiophene (ITIC). The flexible PBDB‐T:ITIC OSCs exhibit an excellent UV durability compared with the ITO‐based control cell, realized by incorporating an FTE with a tailored absorption at wavelengths <380 nm. The novel FTE developed in this work provides a promising alternative to ITO for use in UV‐durable flexible OSCs, serving as a built‐in UV filter to impede an inevitable UV‐induced degradation in ITO‐based OSCs. [ABSTRACT FROM AUTHOR]

Over the last two decades, we have witnessed growing empirical research on the concept of innovation climate at both the team and organizational levels. This article systematically reviews the literature surrounding the concept, focusing on its antecedents and outcomes, and empirical work where it has been treated as a moderator. Based on the review, we propose an agenda for future research that highlights the need to incorporate alternative theoretical perspectives to enhance our understanding of the innovation climate concept and its impact in driving team‐ and organizational‐level outcomes. In addition to theoretical future research strands, we also highlight opportunities for empirical advancement of the field. In particular, we highlight the need to examine the negative influence of innovation climate, adopt a more dynamic approach to examine how innovation climates develops over time, and explore the influence of cultural and institutional factors on the development of innovation climate. Practitioner Points: Innovation is essential for organizations wishing to remain competitive and thrive in the highly competitive global marketplace.This study consolidates the insights from prior research linking leadership and team/demographic/workplace characteristics to both the team innovation climate and the organizational innovation climate.Understanding innovation climate provides practitioners with insight into the levers they may utilize to encourage innovation within the organization.In addition, the outcomes of innovation climate are synthesized in this paper which provides practitioners with insight into the expected benefits of focusing on developing a climate for innovation. [ABSTRACT FROM AUTHOR]

This paper demonstrates the use of multiple polyethyleneimine (PEI) films acting as interface layers in the inverted organic light-emitting diodes (OLEDs) to solve the mixing problem between different functional layers. The morphological, electrical and photoluminescence characteristics of PEI films are systematically investigated. The thickness of PEI layers is optimized to achieve both good electron transport and ability of preventing the miscibility. The authors' results show that the insertion of double PEI interface layers in the inverted OLEDs allow the deposition of electron transport layer and emissive layer all in solution. Finally, the authors report an inverted green OLED with one and double PEI interface layers. The green OLED with double PEI interface layers yields a maximum current efficiency of 45.2 cd A-1, which is close to the device using thermal deposition method. The authors thus believe that the application of multiple PEI interface layers could provide a promising way to obtain highly efficient OLEDs in solution processing. [ABSTRACT FROM AUTHOR]

We have systematically investigated hole/electron distribution and exciton dynamics in blue fluorescent and yellow phosphorescent organic light-emitting diodes (OLEDs). We demonstrate that the importance of appropriate charge carrier confinement and exciton management for the realization of highly efficient and stable OLEDs. For yellow phosphorescent device based on Ir(MePQ)2(acac), we have studied the behavior of various intrinsic emission zones on the characteristics of OLEDs with the hole/electron-transporting matrix. The current efficiency increases from 15.7 to 31.7 cd A−1 with the rise in electron-transporting matrix from 20 to 80 nm. We attributed the improved performance to the strong hole-transfer capabilities and relatively weak electron-donating abilities of Ir-complex doped transporting matrix. In contrast, the efficiencies of blue devices decreased with increasing emitting layer (EML), suggesting that the rate of hole-electron pair recombination continuously decrease with the increasing EML thickness due to blue fluorescent dopant hindering hole transfer. In addition, the complementary-color white OLEDs (WOLEDs) with various EML thickness were also demonstrated. Based on their performance, we have found that the use of thin EML in WOLEDs can significantly improve optoelectronic conversion efficiency, whereas deteriorated device properties reversely. [ABSTRACT FROM AUTHOR]

Phosphorescent organic light‐emitting diodes (PhOLEDs) with ultrathin emissive layer (UEML) structure have great potential in solid‐state lighting and display applications due to their relatively simple fabrication process. In this paper, the effect of doped UEML architecture on the performance of orange PhOLEDs is systematically investigated and highly efficient and long‐lifetime devices with the doped UEML structures are successfully constructed. Through strategic exciton management, the probability of exciton recombination is significantly enhanced, while simultaneously that of exciton annihilation is greatly suppressed, along with excellent charge balance. The resulting orange PhOLEDs based on tris[2‐(2‐pyridyl) imidazole] gallium(III):bis (2‐phenylbenzothiazolato) (acetylacetonate) iridium as emitter exhibit a maximum current efficiency of 60.8 cd A−1, power efficiency of 65.8 lm W−1, and external quantum efficiency of 23.4%, respectively. In addition, the doped UEML architecture greatly extends the device operational stability with a nearly fourfold lifetime improvement (time to reduce to 50% of the initial luminance at 2300 cd m−2) over the conventional phosphorescent device with doped bulk emitting layer. This should be the best results reported so far for orange PhOLEDs, indicating the use of doped UEML structure displays great potential value in designing highly efficient and long‐lifetime PhOLEDs. [ABSTRACT FROM AUTHOR]