Two compounds SiC and AlN, normally insoluble in each other below approximately 2000 degrees C, are synthesized as a single-phase solid-solution thin film by molecular beam epitaxy at 750 degrees C. The growth of epitaxial SiCAlN films with hexagonal structure takes place on 6H-SiC(0001) substrates. Two structural models for the hexagonal SiCAlN films are constructed based on first-principles total-energy density functional theory calculations, each showing agreement with the experimental microstructures observed in cross-sectional transmission electron microscopy images. The predicted fundamental band gap is 3.2 eV for the stoichiometric SiCAlN film.
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http://dx.doi.org/10.1103/PhysRevLett.88.206102 | DOI Listing |
Sci Rep
January 2025
Laboratory for Thin Film Energy Materials, Department of Materials and Environmental Technology, School of Engineering, Tallinn University of Technology, Ehitajate tee 5, Tallinn, 19086, Estonia.
NiO, a wide band gap hole-transporting material (HTM), is gaining attention in photovoltaics due to its optical transparency, chemical stability, and favourable band alignment with absorber. This study uses NiO nanoparticle-based HTM in semi-transparent SbS solar cells via a simple chemical precipitation method. We optimised NiO layer by varying precursor solution concentration and studied its impact on optical and structural properties, composition of nanoparticles and subsequent effect on the performance of semi-transparent SbS solar cell.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, Aarhus C 8000, Denmark.
Superlattices from twisted graphene mono- and bilayer systems give rise to on-demand many-body states such as Mott insulators and unconventional superconductors. These phenomena are ascribed to a combination of flat bands and strong Coulomb interactions. However, a comprehensive understanding is lacking because the low-energy band structure strongly changes when an electric field is applied to vary the electron filling.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China. Electronic address:
An in situ self-cleaning covalent organic framework featuring arylbiguanide arms (Aryl-BIG-COF) was first developed to remove emerging organic pollutants such as propranolol (PRO) from water. The main breakthroughs addressed the scarcity of functional active sites, the impracticality of ex situ regeneration, and the rapid recombination of electronhole pairs in the application of COFs. Owing to the directional capture ability and electronic structure regulation of the arylbiguanide arms, the adsorption capacity and photocatalytic degradation rate of the newly synthesized COF increased by nearly four and seven times, respectively.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Department of Chemistry, Quaid-i-Azam University, Islamabad, 45320, Pakistan.
From synthesis to application, there are always certain interactions between the polar solvents and perovskite nanocrystals (NCs). To explain the effect of solvent polarity especially on the photoluminescence (PL) properties of NCs is highly desirable, especially for sensing applications. Herein We have synthesized the methylammonium lead mixed halides (MAPbClBr, where n = 0, 0.
View Article and Find Full Text PDFChemistry
January 2025
Yamaguchi University, Department of Chemistry, 753-8512, Yamaguchi, JAPAN.
We report herein the synthesis of an unprecedented isomer of perylene, dicyclohepta[cd,fg]-as-indacene bearing two phenyl groups (1-Ph) by the nickel-mediated intramolecular homocoupling of a 4,4'-biazulene derivative (2). The X-ray crystallographic analysis and theoretical calculations revealed that 1-Ph adopts a unique helically twisted geometry although the local aromaticity of azulene moieties was preserved. The double covalent linkage of the two azulene skeletons imparts significant orbital interaction, which affords near-infrared (NIR) absorption (up to 1720 nm) and remarkable redox behaviors despite its closed-shell electronic structure.
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