The surface morphology of CeO(2)(111) single crystals and silicon supported ceria films is investigated by non-contact atomic force microscopy (NC-AFM) and Kelvin probe force microscopy (KPFM) for various annealing conditions. Annealing bulk samples at 1100 K results in small terraces with rounded ledges and steps with predominantly one O-Ce-O triple layer height while annealing at 1200 K produces well-ordered straight step edges in a hexagonal motif and step bunching. The morphology and topographic details of films are similar, however, films are destroyed upon heating them above 1100 K. KPFM images exhibit uniform terraces on a single crystal surface when the crystal is slowly cooled down, whereas rapid cooling results in a significant inhomogeneity of the surface potential. For films exhibiting large terraces, significant inhomogeneity in the KPFM signal is found even for best possible preparation conditions. Applying X-ray photoelectron spectroscopy (XPS), we find a significant contamination of the bulk ceria sample with fluorine while a possible fluorine contamination of the ceria film is below the XPS detection threshold. Time-of-flight secondary ion mass spectroscopy (TOF-SIMS) reveals an accumulation of fluorine within the first 5 nm below the surface of the bulk sample and a small concentration throughout the crystal.
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http://dx.doi.org/10.1039/c2cp42733h | DOI Listing |
RSC Adv
January 2025
Institute of Polymer and Dye Technology, Lodz University of Technology Stefanowskiego 16 Lodz 90537 Poland.
This study investigates the structure-property relationships of a series of phenylhydrazones bearing various electron-donating and electron-withdrawing substituents, such as methoxy, dimethylamino, morpholinyl, hydroxyl, chloro, bromo, and nitro groups. The compounds were synthesized, and their structures were characterized using single-crystal X-ray diffraction, powder X-ray diffraction, FTIR spectroscopy, NMR spectroscopy, and DSC. Three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy and UV-Vis spectroscopy were employed to elucidate the complex interplay between the molecular skeleton, substituents, and the resulting photophysical properties.
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January 2025
Department of Chemical Engineering and Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology 5600 MB Eindhoven The Netherlands
Using photoswitchable molecules to manipulate supramolecular interactions under light illumination has driven advancements in numerous fields, allowing for the strategic alteration of molecular systems. However, integrating the moiety responsible for these interactions into the photochromic scaffold can be complex and may hamper the switching efficiency. We thus explored a simple class of organic molecules, namely thiosemicarbazones, featuring both a photoisomerizable C[double bond, length as m-dash]N double bond and a thiourea moiety capable of hydrogen bonding.
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January 2025
Department of Applied Chemistry, ZHCET, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh, Uttar Pradesh 202002, India.
Herein, we have synthesized a Co(II)-based 2D coordination polymer [Co(5-AIA)(Imidazole)] () (AIA = 5-aminoisophthalic acid) via a solvothermal approach. SCXRD (single-crystal X-ray diffraction) was utilized to analyze the crystal structure of fabricated . Moreover, PXRD, TGA, FTIR, and SEM analyses were done to identify the structural features of fabricated .
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January 2025
Department of Chemistry-BMC Biochemistry, University of Uppsala, Husargatan 3, Uppsala 75237, Sweden.
In this work, we present the synthesis, solid-state characterization, and studies of two pyrazole derivatives: 5-(2-methylphenoxy)-3-methyl-1-phenyl-1-pyrazole-4-carbaldehyde (I) and 5-(4-methylphenoxy)-3-methyl-1-phenyl-1-pyrazole-4-carbaldehyde (II). The molecular crystal properties, in terms of intermolecular hydrogen bonds and other weak interactions, are analyzed using single crystal X-ray diffraction. The Hirshfeld surfaces computational method is used to quantify the intermolecular interactions, density functional theory for theoretical structural optimization, and its comparison with the experimental structure and studies using docking and molecular dynamics studies of I and II with CDC7-kinase.
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January 2025
Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr Homi Bhabha Road, Pune-411008, India.
A superhelix is a three-dimensional arrangement of a helix in which the helix is coiled around a common axis. Here, we are reporting a short 12-helix of α,γ-hybrid peptides terminated by metal binding ligands, self-assembled into a right-handed superhelix around a common axis in the presence of Cd(II) ions. Furthermore, these superhelices are assembled into hierarchical superhelical β-sheet-type structural motifs in single crystals.
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