Hybrid materials based on phthalocyanines and metal nanoparticles for chemiresistive and electrochemical sensors: a mini-review

Synergetic combination of the properties of phthalocyanines and metal nanoparticles is known to result in the improvement of various properties of their hybrid materials. This review provides an overview of the application of hybrid materials based on phthalocyanines and metal nanoparticles for the development of chemiresistive and electrochemical sensors, with a focus on methods and approaches for their preparation

Effects of annealing on device parameters of organic field effect transistors using liquid-crystalline tetrasubstituted zinc phthalocyanine

The device performance of organic thin-film transistors (OTFTs) employing the solution processed films of room temperature liquid-crystalline tetrasubstituted zinc phthalocyanine derivative was found to depend upon the film morphology. Atomic force microscopic and X-Ray diffraction studies show that the annealing at 70° produced a preferentially unidirectional void-free film with improved surface smoothness. The OTFTs with the annealed films exhibited enhanced conductivity, threefold reduction in threshold voltage, a nearly one order of magnitude increase in the on/off ratio and more than one-third reduction of hysteresis in the transfer characteristics.This work is sponsored by the Air Force Office of Scientific Research, Air Force Material Command, USAF, under grant No. FA8655-13-1-3018. TB acknowledges the financial support from the Ministry of Education and Science of the Russian Federation

Mechanism of dicarbonyl(2,4-pentanedionato)iridium(I) decomposition on iron surface and in gas phase: Complex experimental and theoretical study

The mechanism of thermal destruction of Ir(acac)(CO)2 as one of the most important MOCVD precursors for Ir coatings deposition was proposed on the footing of the in situ mass spectrometry analysis and quantum chemical modeling. Calculated structural parameters and vibrational spectra of Ir(acac)(CO)2 molecule were found to be in a fairly good agreement with the experimental data. Ir(acac)(CO)2 was found to unlikely decompose in the gaseous phase while its adsorption onto the iron surface leads to major structural distortions easing the bond cleavage, molecule decomposition with subsequent formation of iridium films

A glucose biosensor based on novel Lutetium bis-phthalocyanine incorporated silica-polyaniline conducting nanobeads

The facile preparation of highly sensitive electrochemical bioprobe based on lutetium 13 phthalocyanine incorporated silica nanoparticles (SiO2(LuPc2)) grafted with Poly(vinyl 14 alcohol-vinyl acetate) itaconic acid (PANI(PVIA)) doped polyaniline conducting nanobeads 15 (SiO2(LuPc2)PANI(PVIA)-CNB) is reported. The preparation of CNB involves two stages (i) 16 pristine synthesis of LuPc2 incorporated SiO2 and PANI(PVIA); (ii) covalent grafting of 17 PANI(PVIA) onto the surface of SiO2(LuPc2). The morphology and other physico-chemical 18 characteristics of CNB were investigated. The scanning electron microscopy images show 19 that the average particle size of SiO2(LuPc2)PANI(PVIA)-CNB was between 180-220 nm. 20 The amperometric measurements showed that the fabricated SiO2(LuPc2)PANI(PVIA)-21 CNB/GOx biosensor exhibited wide linear range (1-16 mM) detection of glucose with a low 22 detection limit of 0.1 mM. SiO2(LuPc2)PANI(PVIA)-CNB/GOx biosensor exhibited high 23 sensitivity (38.53 μA mM−1 cm−2) towards the detection of glucose under optimized 24 conditions. Besides, the real (juice and serum) sample analysis based on a standard addition 25 method and direct detection method showed high precision for measuring glucose at 26 SiO2(LuPc2)PANI(PVIA)-CNB/GOx biosensor. The SiO2(LuPc2)PANI(PVIA)-CNB/GOx 27 biosensor stored under refrigerated condition over a period of 45 days retains ~ 96.4 % 28 glucose response current

Effect of fluorosubstitution on the structure of single crystals, thin films and spectral properties of palladium phthalocyanines

In this work, the crystalline structure of single crystals grown by vacuum sublimation of unsubstituted palladium phthalocyanines (PdPc), its tetrafluorinated (PdPcF4) and hexadecafluorinated (PdPcF16) derivatives have been investigated using X-ray diffraction measurements. Two crystalline phases have been identified for PdPc; the molecules in both phases crystallize in stacks with herringbone arrangement in the monoclinic space groups (C2/c for -PdPc; P21/n for -PdPc). Both PdPcF4 and PdPcF16 crystallize in the triclinic P-1 space group, forming stacks of molecules in columnar arrangement with molecules in adjacent columns are aligned parallel to one another. X-ray diffraction measurements have also been used to elucidate the structural features and molecular orientation of thin films of PdPc, PdPcF4 and PdPcF16, grown by organic molecular beam deposition at different substrate temperatures. The effect of fluorosubstitution on UV-visible optical absorption and vibrational spectra of palladium phthalocyanine derivatives is also discussed

Probing a Complex of Cytochromecand Cardiolipin by Magnetic Circular Dichroism Spectroscopy: Implications for the Initial Events in Apoptosis

Oxidation of cardiolipin (CL) by its complex with cytochrome c (cyt c) plays a crucial role in triggering apoptosis. Through a combination of magnetic circular dichroism spectroscopy and potentiometric titrations, we show that both the ferric and ferrous forms of the heme group of a CL:cyt c complex exist as multiple conformers at a physiologically relevant pH of 7.4. For the ferric state, these conformers are His/Lys- and His/OH–-ligated. The ferrous state is predominantly high-spin and, most likely, His/–. Interconversion of the ferric and ferrous conformers is described by a single midpoint potential of -80 ± 9 mV vs SHE. These results suggest that CL oxidation in mitochondria could occur by the reaction of molecular oxygen with the ferrous CL:cyt c complex in addition to the well-described reaction of peroxides with the ferric form

Relativistic Laser-Matter Interaction and Relativistic Laboratory Astrophysics

The paper is devoted to the prospects of using the laser radiation interaction with plasmas in the laboratory relativistic astrophysics context. We discuss the dimensionless parameters characterizing the processes in the laser and astrophysical plasmas and emphasize a similarity between the laser and astrophysical plasmas in the ultrarelativistic energy limit. In particular, we address basic mechanisms of the charged particle acceleration, the collisionless shock wave and magnetic reconnection and vortex dynamics properties relevant to the problem of ultrarelativistic particle acceleration.Comment: 58 pages, 19 figure

Fragmentation and Multifragmentation of 10.6A GeV Gold Nuclei

We present the results of a study performed on the interactions of 10.6A GeV gold nuclei in nuclear emulsions. In a minimum bias sample of 1311 interac- tions, 5260 helium nuclei and 2622 heavy fragments were observed as Au projec- tile fragments. The experimental data are analyzed with particular emphasis of target separation interactions in emulsions and study of criticalexponents. Multiplicity distributions of the fast-moving projectile fragments are inves- tigated. Charged fragment moments, conditional moments as well as two and three -body asymmetries of the fast moving projectile particles are determined in terms of the total charge remaining bound in the multiply charged projectile fragments. Some differences in the average yields of helium nuclei and heavier fragments are observed, which may be attributed to a target effect. However, two and three-body asymmetries and conditional moments indicate that the breakup mechanism of the projectile seems to be independent of target mass. We looked for evidence of critical point observable in finite nuclei by study the resulting charged fragments distributions. We have obtained the values for the critical exponents gamma, beta and tau and compare our results with those at lower energy experiment (1.0A GeV data). The values suggest that a phase transition like behavior, is observed.Comment: latex, revtex, 28 pages, 12 figures, 3tables, submitted to Europysics Journal