Much attention has been given to detection and monitoring of hydrazine-based compounds in recent time because of its significant negative impacts on human health and ecosystem (aquatic lives). This prompted the current study focusing on detection of 2, 4-dinitrophenylhydrazine (2, 4-dnphz) using electrochemically synthesized poly-para amino benzoic acid-manganese oxide (P-pABA-MnO<sub>2</sub>) composite film. The synthesized P-pABA-MnO<sub>2</sub> composite film was characterized in terms of its structural and morphological properties by X-ray diffraction spectroscopy and field emission scanning electron microscopy respectively. In addition, functionalities and binding energy of p-PABA-MnO2 were confirmed using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy respectively. Finally, electrochemical properties were investigated using electrochemical impedance spectroscopy and cyclic voltammetry. The synthesized P-pABA-MnO<sub>2</sub> displayed good electrocatalytic reduction property towards 2, 4-dnphz with ultra-low limit of detection (0.08 μM; S/N = 3) and very high sensitivity (52 μAμ<sup>-1</sup>Mcm<sup>-2</sup>). The proposed sensor based on P-pABA-MnO<sub>2</sub> also demonstrated good stability in terms of repeatability, reproducibility and interferents effects. Lastly, the proposed sensor was satisfactorily used in detection of 2, 4-dnphz in environmental real samples.
The 2-{4-[2-benzylidenehydrazino]phenyl}ethylene-1,1,2-tricarbonitrile (System 1), 2-{4-[2-(1-naphthylmethylene)hydrazino]phenyl}ethylene-1,1,2-tricarbonitrile (System 2) and 2-{4-[2-(9-anthrylmethylene)- hydrazino]phenyl}ethylene-1,1,2-tricarbonitrile (System 3) were synthesized by direct tricyanovinylation of hydrazones. The bathochromic shift in absorption spectra has been observed by increasing the solvent polarity. The FTIR spectra of these new dyes exhibited three important absorption bands. The first band centered near 3260 cm-1 in System 1 while 3208 cm-1 and 3211 cm-1 in System 2 and System 3 for the nNH absorption, respectively. The second band is a sharp absorption band in the region of 2212-2209 cm-1, which was attributed to the cyano group absorption. The third is an absorption band in the region of 1611-1603 cm-1 ascribed for the C=N. Density functional theory (DFT) calculation of relative energies, relative enthalpies and free energies shows that E isomers are the most stable except System 3 in which the most stable is Z isomers. The conformational energy profile shows two maxima near (-90 and 90o) while three local minima observed at (-180, 0 and 180) for N1-N2-C1-C2 torsional angle. The highest occupied molecular orbitals (HOMOs) are localized on the whole molecules while lowest unoccupied molecular orbitals (LUMOs) are distributed on the tricarbonitrile. KEY WORDS: Dye-sensitized solar cells, HOMO, LUMO, Absorption, FTIR spectra Bull. Chem. Soc. Ethiop. 2015, 29(1), 137-148DOI: http://dx.doi.org/10.4314/bcse.v29i1.13
A novel procedure for the preparation of few-layers boron nitride (BN), either as films or as suspended BN platelets, is presented, based on the pyrolysis of chitosan, which serves both as a matrix to embed ammonium borate and as a template for BN synthesis. The resulting BN samples are characterized by XRD, Raman and X-ray photoelectron spectroscopy, and by TEM and AFM imaging. The samples exhibit deep UV emission, which is characteristic of high quality BN. This template synthesis and the easy exfoliation of BN platelets facilitate the use of BN as an extremely high-efficiency Fenton catalyst for the generation of highly aggressive hydroxyl radicals in water.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ZSM‐5/PEG composites were synthesized by a simple solution method with polyethylene glycol (PEG) and H‐ZSM‐5 zeolite (Si/Al = 11.4). The obtained composites were characterized using X‐ray powder diffraction and Fourier transform infrared spectroscopy. The obtained results indicated that the ZSM‐5 was physically combined with PEG. The thermal properties and thermal stability were investigated by thermogravimetric and differential thermal analyses. In situ electrical conductivity was used to follow‐up the changes in the electrical conductance during the heating of the ZSM‐5/PEG composite. It was found that ZSM‐5 is able to effectively enhance the electrical conductivity of PEG. The results showed that the obtained weight loss during the composite decomposition to charcoal is accompanied by a decrease in the electrical conductivity. Moreover, the removal of the formed charcoal is associated with an electrical conductivity increase. Calcining the ZSM‐5/PEG composite having a content of 30% results in many effects on the structural, textural, and electrical properties of the obtained products. POLYM. COMPOS., 35:1160–1168, 2014. © 2013 Society of Plastics Engineers
Cobalt phosphate (CoPi) nanoplates can be integrated with graphene oxide (GO) by photochemical deposition from an aqueous solution under visible-light illumination using GO as a photocatalyst. The use of the CoPi/GO composites as an oxygen-evolving catalyst with high efficiency is demonstrated. Integrating CoPi with GO leads to reduction of the overvoltage and enhancement of the photocurrent. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
