Mixed Ruddlesden-Popper (RP) perovskites are of great interest in light-emitting diodes (LEDs), due to the efficient energy transfer (funneling) from high-bandgap (donor) domains to low-bandgap (acceptor) domains, which leads to enhanced photoluminescence (PL) intensity, long PL lifetime, and high-efficiency LEDs. However, the influence of reduced effective emitter centers in the active emissive film, as well as the implications of electrical injection into the larger bandgap donor material, have not been addressed in the context of an active device. The electrical and optical signatures of the energy cascading mechanisms are critically assessed and modulated in a model RP perovskite series ((C H NH ) (CH(NH ) ) Pb Br ). Optimized devices demonstrate a current efficiency of 22.9 cd A and 5% external quantum efficiency, more than five times higher than systems where funneling is absent. The signature of nonideal funneling in RP perovskites is revealed by the appearance of donor electroluminescence from the device, followed by a reduction in the LED performance.
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http://dx.doi.org/10.1002/adma.201800818 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Colour Science and Textile Chemistry Research Center, College of Textiles and Clothing, Qingdao University, Qingdao, Shandong 266071, China.
Superhydrophobic fabrics suffer from being commonly penetrated by moisture after laundering, seriously deteriorating their water repellency after air drying. Numerous researchers have successfully recovered superhydrophobicity by drying in fluid ovens; however, high energy consumption and equipment dependence limit practical applications. Herein, the superhydrophobic photothermal self-healing cotton fabric (SPS cotton fabric) was fabricated by depositing a composite layer of cellulose nanocrystal-MXene (C-MXene) and polyacrylate (PA) coatings on the cotton cloth.
View Article and Find Full Text PDFLangmuir
January 2025
Department of Chemical Engineering, Canakkale Onsekiz Mart University,17100 Canakkale, Turkey.
Radioactive iodine, a key waste product of nuclear energy, has been a significant concern among nuclear materials because of its high volatility and its ability to easily enter the human metabolism. Porous materials containing a large number of N-heterocyclic units such as carbazole in the skeletons use as effective adsorbents showing high iodine capture capacities. Herein, a new carbazole-bismaleimide-based hyper-cross-linked porous organic polymer (CzBMI-POP) was successfully prepared from a new tetra-armed carbazole-maleimide monomer (Bis-Cz(BMI)), which contains biscarbazole units and maleimide side groups.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Clean Energy Research Center, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan.
Thermoelectric (TE) devices recycle high-temperature waste-heat efficiently, but waste-heat below sub-250 °C remains uncaptured. As promoting full autonomy for the Internet of Things (IoT), we present a TE generator using multilayered pseudo--type GaN/TiN/GaN and -type TiO/TiN/TiO TE one-leg devices, where heterozygous of outer/inner layers demonstrates the functions of a colossal Seebeck coefficient ( = +15,000 μV K) with phonon-assist hopping, controlling by the porosity for reducing thermal conductivity (κ), a high electric conductivity (σ) with reducing κ by outer layers, and σ- coexistence over singular curve by the asymmetric electrode configuration. is elucidated hopping among inner grains and the space charge (SC) grain boundary (GB) of 100 μm regions within Debye length.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2025
École polytechnique fédérale de Lausanne, School of Engineering, Institute of Mechanical Engineering, Unsteady Flow Diagnostics Laboratory, Lausanne 1015, Switzerland.
Airborne insects generate a leading edge vortex when they flap their wings. This coherent vortex is a low-pressure region that enhances the lift of flapping wings compared to fixed wings. Insect wings are thin membranes strengthened by a system of veins that does not allow large wing deformations.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Materials Science and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Trivandrum 695 019, Kerala, India.
Lightweight flexible piezoelectric devices have garnered significant interest over the past few decades due to their applications as energy harvesters and wearable sensors. Among different piezoelectrically active polymers, poly(vinylidene fluoride) and its copolymers have attracted considerable attention for energy conversion due to their high flexibility, thermal stability, and biocompatibility. However, the orientation of polymer chains for self-poling under mild conditions is still a challenging task.
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