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Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, new metallophthalocyanines (MPc) were synthesized by cyclotetramerization of 4-{[4-(2-morpholin-4-ylethoxy)benzyl]oxy}phthalonitrile. To increase potential application of MPcs, redox active Co(II), Mn(III) and Ti(IV)O metal centers were preferred. MPcs were decorated with redox active and electropolymerizable {[4-(2-morpholin-4-ylethoxy)benzyl]oxy} substituents in order to coat the complexes with electropolymerization. Synthesized MPcs were characterized with UV-Vis, IR, ¹H-NMR, 13C-NMR and MS (ES+ and MALDI-TOF) spectroscopies and voltammetry and in situ spectroelectrochemistry techniques. Voltammetric and in situ spectroelectrochemical analyses indicated that all complexes gave metal based reduction processes in addition to the Pc based processes. During oxidation reaction, all complexes were coated on the glassy carbon electrode (GCE) surface with oxidative electropolymerization reactions. Redox active and conductive GCE/MPc electrodes were constructed with the electropolymerization of MPcs and these electrodes were tested as active pesticide sensors for eserine, parathion, diazinon and fenitrothion pesticides. CoPc did not interact with any pesticide compound while MnPc and TiOPc selectively sensed diazinon and eserine, respectively. [ABSTRACT FROM AUTHOR]

Novel metal-free and metallophthalocyanines were synthesized by cyclotetramerization of 3-(2,3-dihydro- 1H-inden-5-yloxy)phthalonitrile and characterized. The redox properties of these compounds were investigated by cyclic voltammetry, squarewave voltammetry, controlled-potential coulometry and in situ spectroelectrochemistry in dimethylsulfoxide and dichloromethane. The compounds displayed metal and/or phthalocyanine ring-based reduction and oxidation processes. The color changes associated with these redox processes and electrogenerated anionic and cationic redox species were recorded with in situ electrocolorimetric measurements. The electrocatalytic performances of the compounds toward oxygen reduction reaction having vital importance for fuel cell applications were determined by hydrodynamic rotating disk and bipotentiostatic rotating ring-disk voltammetry measurements. The Vulcan XC-72/Nf/FePc modified glassy carbon electrode showed much higher catalytic performance toward oxygen reduction than those of the other modified ones. Furthermore, the field dependence of dielectric response and the conductivity of the samples were measured as a function of frequency and temperature. Dielectric relaxation behaviors of the phthalocyanines were also investigated. The ITO/ZnPc/Au sample showed the highest value of ε'(ω) as compared to the other samples. The analysis of the real and imaginary parts of the dielectric permittivity with frequency was carried out assuming a distribution of relaxation times as well as the scaling behavior of the dielectric loss spectra. [ABSTRACT FROM AUTHOR]

Precious-metal-free cathode catalysts have been intensively developed for realization of the widespread use of polymer electrolyte fuel cells, although their activity and durability should be further increased. In this study, a carbonaceous catalyst for the oxygen reduction was formed using phthalonitrile derivatives (PNDs) as the carbon and nitrogen sources, and cobalt chloride as the template and active site sources by heat-treatment at 700°C. The heat-treatment of the mixture of PNDs and CoCl2 generated Co(0) aggregates or Co2(OH)3Cl depending on the kind of PNDs by the interaction between the PNDs and CoCl2, and the generation of the latter resulted in the development of micropores in the carbonaceous catalysts with the characteristic flaky structure and high oxygen reduction activity. The activity was enhanced by the addition of a small amount of FeCl2. The heat-treatment at 900°C in addition to the heat-treatment at 700°C resulted in an improved fuel cell performance. The maximum power densities reached 0.25 and 0.1 W cm-2 under the supplied H2/O2 and H2/air at atmospheric pressure, respectively. The stability of the catalyst was improved by the two-step heat-treatment, which was associated with the local structure change around the metals. [ABSTRACT FROM AUTHOR]

The photosensitive resin used in additive manufacturing is cured by free radical polymerization by UV irradiation. However, undesired reaction with oxygen during polymerization inhibits polymerization and results in an under-cured polymer. Therefore, in this study, the hypothesis that successful oxygen shielding in the post-polymerization step could affect the properties of the final polymer was tested. 3D printed specimens using denture base resin were post polymerized either by immersion in glycerin for oxygen shielding (GL group) or placed in a medium-low vacuum chamber at 5 × 10−2 Torr (VA group). Specimens cured with no additional conditioning served as the control (CON group). To consider the effect of temperature, all groups were additionally compared with 80 °C and without an increase in temperature (room temperature) during post-polymerization. Fourier transform infrared spectroscopy was used to measure the monomer conversion ratios between different groups. In addition, the mechanical properties were quantified by the micro-hardness, flexural strength, and elasticity of the surface, and the water sorption and solubility. Dynamic mechanical analysis (DMA) was conducted to observe the trend in storage and loss modulus between the groups against temperature. Differences in the surface as a function of the post-polymerization conditions were qualitatively observed by scanning electron microscopy (SEM). The result shows that oxygen shielding during post-polymerization showed an increase in the degree of conversion (DC) and hardness of the resin surface. The highest DC was observed for GL group specimens at both room temperature and 80 °C. This result was confirmed by the SEM micrographs of the resin surface, where the interface between the layers of the GL group structure becomes more robust. However, a difference was observed between the samples prepared at room temperature and 80 °C. The flexural modulus was highest in the GL group, followed by the VA group, and lowest in the CON group at 80 °C. No difference in water absorption was observed for any groups, but high water solubility was observed in the GL group at room temperature. Overall, more significant differences in the properties were observed for the samples post-polymerized at 80 °C than at room temperature. The results of DMA analysis to determine the glass transition temperature showed a similar trend in all groups, and the storage modulus and loss rate obtained in the same experiment decreased in the order of GL, CON, and VA. In conclusion, an oxygen shielded post-polymerization environment at elevated temperature effectively improves the mechanical properties of photosensitive resin. [Display omitted] • Oxygen shielding during post-polymerization enhances resin surface properties. • Glycerin and low pressure vacuum improve polymerization percentage and microhardness. • Increased temperature and oxygen shielding have additive impact on properties. • Glycerin presents better outcome to vacuum oxygen shielding in post-polymerization. [ABSTRACT FROM AUTHOR]

Abstract: According to the low power and the chemical modifiction properties of organic gas-sensing material, the organic semiconductor material of molecule hybrid CuPc and PANI was used as gas-sensing film, and the gas sensor which has high selectivity to toxic gas was investigated. CuPc was synthesized with Phthalonitrile and p-Cresol as the source material of benzene ring by the template synthesis method of two steps reaction. Through doping with perchloric acid, vitriol and nitric acid, semiconducting doped PANI was obtained. By means of molecular hybrid modification, the intermediate substance of CuPc and PANI was polymerized and formed a kind of new organic semiconductor material CuPcxPANI1-x. Sensor chip was made by virtue of semiconductor technology; the combination of chip and new sensitive material was achieved by virtue of vacuum coating technology. The film surface morphology were characterized through SEM, and it showed that the sensitive material was made of rounded particles whose diameter was about 200nm; the surface of film was deposited by odontoid particals, whose diameter is 200nm or so, and relatively uniform, and its aperture is ordered. The gas sensing properties of thin film were tested by static volumetric method. The results indicate that the new organic semiconductor hybrid material is sensitive to the toxic gases of sulfur dioxide, nitride dioxide, chlorine ect.; the selectivity can be improved by changing the ratio of the distribution; When the heating voltage is 1.5V, the output resistance can be stabilized within 5% and the sensitivity within 10% in 6 months. [Copyright &y& Elsevier]

Abstract: CuPc was synthesized with 4-Nitrophthalonitrile and p-Cresol as the source materials of benzene ring by the template synthesis method of two steps reaction. With aniline as the source material of polyaniline, using chemical oxidative polymerization method of one-step reaction, through doping with perchloric acid, vitriol and nitric acid obtained semiconducting doped PANI. On this basis, selected the intermediate substance of reactive process, by means of molecular hybrid modification polymerized the two substances to form a kind of new organic semiconductor material CuPcxPANI1-x. Through the analysis of characterization means such as mass-spectrometry, infrared absorption spectroscopyand thermogravimetry, the results indicated that molecular weight of the phthalocyanin molecular fragment was confirmed as 234 through the analysis of mass-spectrometry, and the theoretical value of phthalocyanin was 234.34, which validated that the synthesis process of the phthalocyanin molecular fragment was right. Through the analysis of thermogravimetry, the new substance from hybrid synthesis forming thin film was viable using the technology of evaporation. [Copyright &y& Elsevier]

A novel 2-D complex [Cu(nbdc)(phen)(H[sub2]O)] (nbdc = 2-nitro-1,4-benzenedicarboxylate dianion and phen = 1,10-phenanthroline) has been synthesized and structurally characterized by single crystal X-ray analysis. It exhibits nice fluorescent property. The modifying group plays a key role in the assembly of the framework. [ABSTRACT FROM AUTHOR]