scholarly journals Self-Assembly of a Carboxyl-Functionalized BODIPY Dye via Hydrogen Bonding

Crystals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 436 ◽  
Author(s):  
Beatriz Matarranz ◽  
Angel Sampedro ◽  
Constantin G. Daniliuc ◽  
Gustavo Fernández

We report the synthesis, characterization, and self-assembly behavior of a 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dye functionalized at the meso-position with a butyric acid group. Various spectroscopic investigations (UV-Vis, emission, and Fourier-transform infrared spectroscopy (FTIR) studies) supported by X-ray analysis revealed the formation of self-assembled structures in the solid state with translationally stacked BODIPY units driven by hydrogen bonding between the carboxyl groups.

1997 ◽  
Vol 50 (10) ◽  
pp. 977 ◽  
Author(s):  
Daniel E. Lynch ◽  
Graham Smith ◽  
Karl A. Byriel ◽  
Colin H. L. Kennard

A series of molecular adducts of the isomeric aminobenzoic acids with the nitro-substituted Lewis bases 2-chloro-5-nitropyridine, 5-nitroquinoline and 5-nitroisoquinoline has been prepared and characterized by using infrared spectroscopy and X-ray powder diffraction, and in four cases by single-crystal X-ray diffraction methods. These four compounds are the adducts of 3-aminobenzoic acid with 5-nitroquinoline [(C7H7NO2)(C9H6N2O2)], 4-aminobenzoic acid with 5-nitroquinoline [(C7H7NO2)2(C9H6N2O2)], 2-aminobenzoic acid with 5-nitroisoquinoline [(C7H7NO2)(C9H6N2O2)] and 4-aminobenzoic acid with 5-nitroisoquinoline [(C7H7N2O2)(C9H6N2O2)]. Other compounds described are the (1 : 1) adducts of 4-aminobenzoic acid with 2-chloro-5-nitropyridine, and 2-aminobenzoic acid with 5-nitroquinoline. All adducts involve hydrogen-bonding network associations while in none of the examples is any proton transfer involved.


2019 ◽  
Vol 70 (8) ◽  
pp. 2747-2752
Author(s):  
Constantin Marutoiu ◽  
Ioan Bratu ◽  
Mircea Gelu Buta ◽  
Olivia Florena Nemes ◽  
Sergiu Petru Timbus(Monk Siluan) ◽  
...  

A two-sided wooden icon from a monastery in Transylvania was submitted for multidisciplinary investigations involving X-Ray Fluorescence, Radiographic Photographyand Fourier Transform Infrared Spectroscopy. The most important part of the icon is St. Nicholas wooden icon, painted over forty years ago. The spectroscopic methods used revealed the painting materials composition, the status of the wooden stage, and the presence of resins as varnish (Fourier Transform Infrared Spectroscopy). On one side, the St Nicholasicon was painted over an old icon, St. Arch. Michael, which was evidenced by X-Ray Photography. The obtained data can serve for the preservation and the restoration of these wooden icons.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4097
Author(s):  
Wooyong Seong ◽  
Hyungwoo Hahm ◽  
Seyong Kim ◽  
Jongwoo Park ◽  
Khalil A. Abboud ◽  
...  

Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) of the bis-urea salen Al catalyst is three times higher than that of a μ-oxo-bridged catalyst, and 13 times higher than that of a monomeric salen aluminum catalyst. The bimetallic reaction pathway is suggested based on urea additive studies and kinetic studies. Additionally, the X-ray crystal structure of a bis-urea salen Ni complex supports the self-assembly of the bis-urea salen metal complex through hydrogen bonding.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 116
Author(s):  
Gian Luca Chiarello ◽  
Ye Lu ◽  
Miren Agote-Arán ◽  
Riccardo Pellegrini ◽  
Davide Ferri

Infrared spectroscopy is typically not used to establish the oxidation state of metal-based catalysts. In this work, we show that the baseline of spectra collected in diffuse reflectance mode of a series of Pd/Al2O3 samples of increasing Pd content varies significantly and reversibly under alternate pulses of CO or H2 and O2. Moreover, these baseline changes are proportional to the Pd content in Pd/Al2O3 samples exhibiting comparable Pd particle size. Similar measurements by X-ray absorption spectroscopy on a different 2 wt.% Pd/Al2O3 confirm that the baseline changes reflect the reversible reduction-oxidation of Pd. Hence, we demonstrate that changes in oxidation state of metal-based catalysts can be determined using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and that this behavior is part of the spectral changes that are returned by experiments under operando conditions.


Author(s):  
Ganghuo Pan ◽  
Jie Leng ◽  
Liye Deng ◽  
Liwen Xing ◽  
Rui Feng

2021 ◽  
pp. 152808372110592
Author(s):  
Vahid Shakeri Siavashani ◽  
Gursoy Nevin ◽  
Majid Montazer ◽  
Pelin Altay

Flexible sensors and wearable electronics have become important in recent years. A good conductive and flexible textile is needed to develop a commercial wearable device. Conductive polymers have generally been used with limitation in reducing the surface resistance to a certain amount. In this research, a method for fabricating a stretchable highly conductive cotton/lycra knitted fabric is introduced by treating the fabric with polypyrrole (PPy), silver nanoparticles (SNPs) composites, and post-treating with poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) (PEDOT:PSS). Polypyrrole and SNPs were in situ fabricated on the cotton/lycra fabric by consecutive redox reaction of silver nitrate and pyrrole and finally covered by PEDOT:PSS solution through dip-coating. The coated textile was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray mapping, and energy dispersive X-ray spectroscopy (EDX). Fourier transform infrared spectroscopy confirmed PPy-SNPs (P-S) composites on the fabric surface. Fourier transform infrared spectroscopy results, X-ray mapping, EDAX, and XRD analysis also confirmed the P-S composites and PEDOT:PSS polymeric layer on the fabric. Morphological observation showed a layer of PEDOT:PSS on the P-S caused the higher connection of coating on textiles which resulted in the higher electrical conductivity (43 s/m). Also morphological observations showed penetration of the silver particles inside fibers which represented improving in attachment and stability of the coating on the fibers. Further, the electrical conductivity of PPy-SNPs-PEDOT:PSS coated textile increased under the tension. Hence, the stretchable and highly conductive knitted cotton/lycra fabric has potentiality to be used for fabricating the flexible sensors or wearable electronics.


Author(s):  
S. J. Pradeeba ◽  
K. Sampath

This research was carried out based on the significance of protecting the environment by preventing the contamination of water caused from effluents discharge from dyeing industries, effective nanocomposite were prepared to solve this problem. The poly(azomethine), ZnO, and poly(azomethine)/ZnO nanocomposites were prepared and characterized by Fourier transform-infrared spectroscopy, ultraviolet (UV)–visible spectroscopy, powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDAX), scanning electron Microscope (SEM), and transmission electron microscopy (TEM) techniques. Methylene blue (MB), Malachite green (MG), and Bismarck brown (BB) were degraded from water using poly(azomethine) (PAZ), zinc oxide (ZnO), PAZ/ZnO (PNZ) nanocomposites as photocatalyst in the presence of natural sunlight. The degradation efficiency and reaction kinetics were calculated, and the outcome of the photocatalytic experiments proved that the PAZ/ZnO nanocomposites reveals excellent photocatalytic activity and effective for decolorization of dye containing waste water than PAZ and ZnO in the presence of natural sunlight. The maximum degradation efficiency 97%, 96%, and 95% was obtained for PNZ nanocomposites at optimum dosage of catalyst as 500 mg and 50 ppm of MB, MG, and BB dye concentration, respectively. The maximum degradation time was 5 h. After photocatalytic study, the samples were characterized by Fourier-transform infrared spectroscopy (FT-IR) and UV–visible spectroscopy.


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