Papers by Keyword: Phthalocyanine

Abstract: Hybrid materials of multi walled carbon nanotubes-zinc phthalocyanine (MWCNTs-ZnPc) and multi walled carbon nanotubes-aluminum phthalocyanine (MWCNTs-AlPc) have been prepared. MWCNTs were treated with mixture of nitric and sulfuric acid pre to the mixing with phthalocyanines for the de-bundling effect. Hybrid materials have been drop casted onto glass slides and interdigitated electrodes from their solution in dimethylformamide. UV-visible absorption spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR) have revealed the successful hybridization due π-π interaction between MWCNTs and phthalocyanine species. I-V measurements and DC conductivity of the hybrid films has been investigated. The behavior of DC electrical conductivity and the activation energy with the variation of temperature were studied.

Abstract: Zinc oxide (ZnO) nanorods were grown on the pre-seeded substrate using a facile, solution route technique. The multilayer self-assembly of polyaniline (PAni) and tetrasulphonated phthalocyanine (TSCuPc) on ZnO nanorods was monitored by FTIR, UV-Vis SEM and XRD. Infrared spectrum of the assembled layer showed peaks centered at 1589cm-1and 1504 cm-1, confirmed the presence of quinoid and benzenoid structures of PAni, while peaks centered at ~1165cm^-1and ~775cm^-1 provided evidence for the presence of TSCuPc species. Absorption spectra of the assembled layer show broadened peaks at ~600nm and ~700nm affirmed the presence of PAni and TSCuPc molecules. A linear increase in the absorbance level at these wavelengths was also observed upon increasing the number of bilayers. The surface modification of the ZnO nanorods after self-assembly was confirmed through SEM. The edges of the ZnO nanorods was observed to change from sharp to dull upon employing layer by layer deposition of PAni and TSCuPc. XRD pattern of the assembled layer showed broadened peaks at low 2Θvalues associated to the amorphous nature of the emeraldine base of PAni. Even so, the diffraction peaks in XRD patterns of ZnO nanorods and ZnO/(TSCuPc-PAni) multilayer have been indexed as hexagonally wurtzite structure. The multilayer deposition of PAni and TSCuPc on the surface of ZnO as monitored by UV-Vis spectroscopy and confirmed by FTIR, XRD, and SEM provides a new way of anchoring dye molecules without carboxylic moieties on the surface of metal oxides

Abstract: A novel supported catalyst is prepared through immobilization of water soluble phthalocyanine, which is synthesized by modifying tetraminophthalocyanine with cyanuric chloride, onto the supporting material Mg-Al hydrotalcite via co-precipitation method. The structure of the catalyst is characterized by infrared spectroscopy instrument (FT-IR) and X-ray diffractometer. Catalytic activity is examined through comparative experiments. The results show that it exhibits high catalytic activity for degradation of methylene blue (MB) in the presence of H₂O₂, the remaining rate of MB is 12.02% after 6 h. The reaction process conforms to the equation of pseudo-first-order kinetics, and the correlation coefficient R²> 0.99. The recycling tests for five times are also carried out and prove its reusability in catalytic application.

Abstract: The nonlinear refraction and absorption properties of a PEI (phthalocyanine indium) tetrasulphonated chlorinated phthalocyanine electrostatic self-assembled film were studied using a simple and high sensitivity technique. We adopted picosecond laser pulses as source light and modified top-hat Zscan technique with a disk and a small aperture to explore the nonlinear refraction of the film. Experimental results show that the measuring sensitivity is increased by two orders of magnitude. Through theoretical fitting, we obtain the nonlinear refraction index and nonlinear absorption coefficients of the film are 2.1×10-14 m2/W and 2.4×10-7 m/W, respectively.

Abstract: Because of the dark green color similar to vegetation, tetranitro iron phthalocyanine has great potentiality in military camouflage application. Tetranitro iron phthalocyanine was synthesized in the method of improved microwave-assisted synthesis. By single-variable controlling principle, the optimal synthesis conditions in laboratory for tetranitro iron phthalocyanine composing was determined. The spectra difference under different conditions between tetranitro iron phthalocyanine and green vegetation was analyzed. The possibility for using tetranitro iron phthalocyanine as green paint in camouflage was discussed

Abstract: The photocatalytic activity of polycrystalline TiO₂ samples impregnated with dendritic zinc phthalocaynine was investigated using the rhodamine B (RhB) aqueous solution as a probe. The morphology and structure of TiO₂/dendrimer phthalocyanine nanocomposite catalyst were characterized by X-ray diffraction (XRD) and UV-Vis spectra. Significant activity improvements of the TiO₂/dendrimer phthalocyanine nanocomposite photocatalyst were observed possible in terms of lower loading amount, enhanced photo-reactivity under light irradiation, as well as chemical, and photochemical stability of the sensitizers.

Abstract: 4, 5-dicyano dimethyl phthalate was an intermediate of the synthesis of phthalocyanine compounds substituted carboxyl. Under the existence of the solvent methanol, 4, 5-dibromo dimethyl phthalate was synthesized by 4,5-Dibromophthalic acid and thionyl chloride.Then it was with cuprous cyanide to get 4,5-dicyano dimethyl phthalate. By studying the process conditions, we got the optimal reaction conditions of 4,5-Dibromo dimethyl phthalate which was thionyl chloride: 4,5-Dibromophthalic acid (2.5:1.0 , molar ratio) and by enlarging 10 times of the experimental conditions, we got the yield 86.4% which was higher than the reported 66.8%.And the optimal reaction conditions of 4,5-dicyano dimethyl phthalate was that high purity argon, absolutely anhydrous DMF, cuprous cyanide and 4,5-Dibromo dimethyl phthalate whose molar ratio were 4.0:1.0. By enlarging 10 times of the experimental conditions, we got the yield 19.0%.

Abstract: While searching for adequate sol-gel methodologies for successfully trapping in monomeric and stable form either porphyrins or phthalocyanines, inside translucent monolithic silica xerogels, it was discovered that the interactions of these trapped tetrapyrrole macrocycles with Si-OH surface groups inhibit or spoil the efficient display of physicochemical, especially optical, properties of the confined species. Consequently, we have developed strategies to keep the inserted macrocycle species as far as possible from these interferences by substituting the surface ^-OH groups for alkyl or aryl groups or trapping these species inside alternative metal oxide networks, such as ZrO₂, TiO₂, and Al₂O₃. In the present manuscript, we present, for the first time to our knowledge, a methodology for preserving the spectroscopic characteristics of metal tetrasulfophthalocyanines and cobalt tetraphenylporphyrins trapped inside the pores of ZrO₂ xerogels. The results obtained are contrasting with analogous silica systems and demonstrate that, in ZrO₂ networks, the macrocyclic species remain trapped in stable and monomeric form while keeping their original spectroscopic characteristics in a better way than when captured inside silica systems. This outcome imply a lower hydrophilic character linked to the existence of a smaller amount of surface hydroxyl groups in ZrO₂ networks, if compared to analogous SiO₂ xerogel systems. The development and study of the possibility of trapping or fixing synthetic or natural tetrapyrrole macrocycles inside inorganic networks suggest the possibility of synthesizing hybrid solid systems suitable for important applications in technological areas such as optics, catalysis, sensoring and medicine

Abstract: Charge transport of pure and composite thin films (20 nm thickness) of cobalt phthalocyanine (CoPc) and iron phthalocyanine (FePc) grown by molecular beam epitaxy has been investigated in the temperature range of 300 K-25 K. Composite films with optimum composition showed very high mobility of 110 cm2V-1s-1 at room temperature. X-ray diffraction and UV-Vis studies showed that the films were well oriented with planar co-facial structure. The current density-voltage (J-V) characteristics of composite films showed trap free space charge limited conduction (SCLC) while individual phthalocyanine films showed SCLC with exponential distribution of traps. Several factors such as effect of substrate, very small thickness and effect of mixing two phthalocyanines are responsible for the very high mobility observed in present study.

Abstract: A chemosensor was designed, and its sensing behavior toward metal ions was investigated by fluorescence spectroscopies. The fluorescence measurements indicated that the PcOC8 has excellent fluorescence emission in methanol solution, and the intensity of fluorescence emission was enhanced by adding Mg (II) ion, whereas other ions including Zn (II), Ba (II), Ca (II), Ni (II), Co (II), Cd (II), Cr (II), Fe (III), Pb (II), Cu (II), and K(I) could quench the intensity of fluorescence emission, which constituted a Mg (II)-selective fluorescent chemosensor.