Furan/phenylene co-oligomer single crystals are considered as future materials for organic optoelectronics. Here, the effects of trifluoromethyl substituents on the crystallization, structure and optical properties of furan/phenylene co-oligomer 1,4-bis{5-[4-(trifluoromethyl)phenyl]furan-2-yl}benzene are studied systematically. The solution growth methods and physical vapor transport result in the formation of three polymorphs depending on the growth method and the solvent. Single-crystal X-ray analysis reveals the crystal structures to correspond to H-, J- or mixed aggregates. All obtained crystals exhibit high photoluminescence efficiency and have optical properties which strongly depend on the crystal packing. Variable-temperature X-ray powder diffraction analysis shows the thermal transition of two forms (H- and J-aggregates) into a third one (mixed aggregate). Terminal trifluoromethyl groups induce weak intermolecular interactions which control the crystal packing and optical properties of co-oligomer single crystals.
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http://dx.doi.org/10.1107/S2052520618011782 | DOI Listing |
J Colloid Interface Sci
December 2024
Institute for Frontier Materials, Deakin University, Geelong VIC 3216, Australia. Electronic address:
Hypothesis: Optimizing interfacial positioning of crosslinkers within a reactive self-assembled hexagonal lyotropic liquid crystals (HLLC) system could assist in retaining the hexagonal structure during polymerization and thereby improving water filtration performances of the as-synthesized nanofiltration membranes.
Experiments: The positioning of the hydrophilic crosslinker, poly (ethylene glycol) diacrylate (PEGDA), within the reactive HLLC system was systematically investigated using H and C solid nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. The structural variation and water filtration performances of these HLLC systems with/without crosslinkers after polymerization were further studied using grazing incidence SAXS (GISAXS) and crossflow filtration tests, respectively.
Sci Rep
December 2024
Centre Énergie, Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650, Blvd, Lionel-Boulet, Varennes, QC, J3X-1P7, Canada.
RF-sputtering is used to deposit TiO-Magneli-phase films onto various substrates at deposition temperatures (T) ranging from 25 to 650 °C. Not only the structural, but also electrical conductivity, optical absorbance and photothermal properties of the TiO films are shown to change significantly with T. A T of 500 °C is pointed out as the optimal temperature that yields highly-crystalized pure-TiO-Magneli phase with a densely-packed morphology and a conductivity as high as 740 S/cm.
View Article and Find Full Text PDFFood Chem
December 2024
Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, 300070 Tianjin, People's Republic of China; Tianjin Key Laboratory of Environment, Nutrition and Public Health, Center for International Collaborative Research on Environment, Nutrition and Public Health, Tianjin Medical University, Tianjin, People's Republic of China. Electronic address:
A novel biomimetic molecular imprinted polymer chip with fluorescence (FL) and structural (STR) states, inspired by color patterns of chameleon skin, is fabricated for detecting diethylstilbestrol (DES). The chip features a regularly structured, non-closed-packed (NCP) colloidal photonic crystal (CPC) lattice made monodisperse MIP spheres containing fluorescence poly ionic liquid (FPIL) pigments. The FL color originates from FPIL pigments and is further enhanced by the Purcell effect, while the STR color results from the periodic arrangement of the NCP CPC structure.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Tongji University, School of Material Science and Engineering, CHINA.
A classical crystallization usually grows epitaxially from a crystal nucleus. Presented in this study is an unusual endotaxy growth manner of a crystalline homopolymer to form hexagonal nanosheets. The amphiphilic homopolymer, poly(3-(4-(phenyldiazenyl)phenoxy)propyl methacrylate) (PAzoPMA), is first annealed in isopropanol to afford a hexagonal nut-like structure.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Tsinghua University, Department of Chemistry, 1 Qinghuayuan, Haidian District, 100084, Beijing, CHINA.
The in-depth research on the charge transport properties of BN-embedded polycyclic aromatic hydrocarbons (BN-PAHs) still lags far behind studies of their emitting properties. Herein, we report the successfully synthesis of novel ladder-type BN-PAHs (BCNL1 and BCNL2) featuring a highly ordered BC3N2 acene unit, achieved via a nitrogen-directed tandem C-H borylation. Single-crystal X-ray diffraction analysis unambiguously revealed their unique and compact herringbone packing structures.
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