Triphenylamine substituted copper and zinc phthalocyanines as alternative hole-transporting materials for solution-processed perovskite solar cells.

In the present study, new peripheral substituted Zn(II) and Cu(II) phthalocyanine derivatives (p-ZnPc and p-CuPc) bearing bulky aromatic triphenylamine groups were synthesized as alternative hole-transporting materials (HTMs). The structures of the new phthalocyanine derivatives (p-ZnPc and p-CuPc) were illuminated by various spectroscopic techniques such as mass spectrometry and 1H, and 13C-NMR. After structural analysis, their photophysical properties in solution and the solid phase were examined by UV-Vis absorption and fluorescence spectroscopy. Using p-ZnPc and p-CuPc as HTMs, highly stable perovskite-based solar cells with the structure of FTO/SnO2/perovskite/p-ZnPc and p-CuPc/Ag have been developed and characterized. It was observed that our devices with p-ZnPc as the HTM maintain over 93% of the initial performance for more than 960 h under atmospheric conditions (22-27 °C) with 35-45% relative humidity. In addition, some strategies such as using various methylammonium iodide (MAI) and lead iodide (PbI2) blend ratios between 1 : 0.4 and 1 : 1.8 were employed to test the effect of the blend ratios on the long term stability of the perovskite-based solar cells. Our findings demonstrated that the spin-coated p-ZnPc based HTM demonstrated competitive power conversion efficiency and exhibited superior stability without encapsulation compared to commonly used HTMs.

Synthesis and photovoltaic properties of novel ferrocene-substituted metallophthalocyanines.

In this paper, a series of new metallophthalocyanines, including ferrocene groups, were designed, synthesized and, characterized, and their photovoltaic properties were investigated as alternative electron-donor materials in bulk heterojunction (BHJ) solar cells. These products were synthesized by a Sonogashira cross-coupling reaction between tetraiodophthalocyanine and ethynyl ferrocene. The newly synthesized phthalocyanines (4-6) were characterized by FT-IR, UV-Vis, 1H NMR, and MALDI-TOF spectroscopic methods and elemental analysis. The electrochemical characterizations were carried out by cyclic voltammetry as well as differential pulse voltammetry. Density functional theory calculations were realized to prove the charge separation between ferrocene as an electron-donor and the phthalocyanine ring as an acceptor. According to UV-Vis measurements, a 25 nm red-shift was observed for complex 4 compared with complexes 5 and 6. Finally, the photovoltaic performance of these compounds used as an electron-donor moiety in a BHJ device were investigated. A function of different blend ratios was tested by fabricating a series of BHJ devices with the architecture of FTO/PEDOT:PSS/4-6: PCBM blend/Ag with an identical thickness of the active layer. The results indicated that the photovoltaic conversion efficiency of BHJ devices exhibited a strong blend-ratio dependence. The maximum power conversion efficiency was obtained by 5-based devices, as 3.65%, with a blend ratio of 1.5 : 1.0 under standard AM 1.5 illumination.

Unsymmetrical zinc phthalocyanines containing thiophene and amine groups as donor for bulk heterojunction solar cells.

Photovoltaic technology is an alternative resource for renewable and sustainable energy and low costs organic photovoltaic devices such as bulk-heterojunction (BHJ) solar cells, which are selective candidates for the effective conversion of solar energy into electricity. Asymmetric phthalocyanines containing electron acceptor and donor groups create high photovoltaic conversion efficiency in dye sensitized solar cells. In this study, a new unsymmetrical zinc phthalocyanine was designed and synthesized including thiophene and amine groups at peripherally positions for BHJ solar cell. The structure of the targeted compound (4) was characterized comprehensively by FT-IR, UV-Vis, 1H-NMR, and MALDI-TOF MS spectroscopies. The potential of this compound in bulk heterojunction (BHJ) photovoltaic devices as donor was also researched as function of blend ratio (blend ratio was varied from 0.5 to 4). For this purpose, a series of BHJ devices with the structure of fluorine doped indium tin oxide (FTO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/ ZnPc:[6,6]- phenyl-C61- butyric acid methyl ester (PCBM) blend/Al with identical thickness of ZnPc:PCBM layer were fabricated and characterized. Photo current measurements in 4 revealed that the observed photo current maximum is consistent with UV-vis spectra of the compound of 4. Preliminary studies showed that the blend ratio has a critical effect on the BHJ device performance parameters. Photovoltaic conversion efficiency of 6.14% was achieved with 4 based BHJ device.

Investigation of the photoconductive properties of thiophene substituted metallo-phthalocyanines.

The synthesis of 4-(thiophen-3-ylethynyl)phthalonitrile was achieved via the Sonogashira cross-coupling reaction. Herein, we report the synthesis of symmetrical metallo-phthalocyanines with cobalt, zinc, and manganese as the metal ions, and tetrakis(ethynylthiophene) groups substituted at the peripheral positions. The new compounds have been characterized by using mass, 1H NMR, 13C NMR, FT-IR and UV-vis spectroscopy. Dark and photoconductivity measurements were carried out on spin coated thiophene substituted metallo-phthalocyanines at various temperatures fixed between 300 and 440 K. Photocurrent generation and charge transport mechanisms are discussed as well. The evaluation of the photoconductive properties of these compounds indicated that the photocurrent generation efficiency and charge transport mechanism exhibited a strong temperature dependence. On the other hand, conductivity measurements revealed that the temperature dependence of the conductivity can be described by the Arrhenius type exponential equation under dark conditions. Furthermore, it was found that the photoconductive behavior of the film can be described successfully by the variable range hopping model for the whole investigated temperature range.

Sensing alcohol vapours with novel unsymmetrically substituted metallophthalocyanines.

Unsymmetrically substituted phthalocyanines were synthesized by the well-known statistical condensation method using two differently substituted precursors, 4-tert-butylphthalonitrile and 4-(4-pyrrol-1-yl)phenoxyphthalonitrile. Spin-coated thin films of these compounds were subsequently exposed to varying concentrations of methanol, ethanol and butanol between 25 and 150 ppm in order to investigate the effects of the number of carbon atoms in the alcohol vapors. The results of this preliminary investigation indicated that sensor performance parameters such as sensitivity, response and recovery time strongly depend on the number of carbon atoms in the analyte molecules. It was found that the sensitivity of the sensors decreases with increasing number of carbon atoms. Electrochemistry studies of CoPc and MnClPc were carried out with cyclic and square wave voltammetry methods. Both complexes illustrated metal and ring-based electron transfer reactions. While CoPc underwent only one metal-based reduction ([CoIIPc2-]/[CoIPc2-]1-), two metal-based reductions ([Cl-MnIIIPc2-]/[Cl-MnIIPc2-]1- and [Cl-MnIIPc2-]1-/[Cl-MnIPc2-]2-) were observed with MnPc. Color changes during the in situ spectroelectrochemical measurements illustrated the versatility of the compounds for display technologies. Pyrrole-containing substituents of the complexes triggered their electropolymerization on the working electrode, which enhances their value as functional materials for modified electrodes.

Electric field assisted deposition of E. coli bacteria into the pores of porous silicon.

The effect of the electric field strength on the Escherichia coli (E. coli) bacteria deposition into the pores of porous silicon was investigated by impedance spectroscopy technique. The main idea behind this approach is that negatively charged E. coli bacteria can be deposited into the pores available on the surface of porous silicon upon the application of a high electric field. For this purpose, the influence of the E. coli concentration on the impedance spectra of the anodically formed porous silicon under various electric fields between 0 and 10 kV/cm was investigated. In addition, the effect of the application time of a constant electric field of 12 kV/cm on the impedance spectra of porous silicon exposed to living and dead bacterial cells was also investigated. The results reported in this study indicate that the number of live E. coli bacteria deposited into the pores of porous silicon can be controlled by the applied electric field strength. On the other hand, it was found that there is no considerable effect of the dead E. coli cell concentration on the recorded impedance spectra of the porous silicon based sensor platform.

π-Extended hexadeca-substituted cobalt phthalocyanine as an active layer for organic field-effect transistors.

Due to their flexibility and solution applicability, organic field-effect transistors (OFETs) are considered prominent candidates for application in flexible and low-cost devices. A soluble phthalocyaninato cobalt(ii) complex was designed and synthesized based on a hexadeca-substitution pattern by introducing peripheral phenylethynyl groups and non-peripheral n-butoxy groups. The cobalt phthalocyanine derivative was characterized using a wide range of spectroscopic and electrochemical methods, as well as single-crystal X-ray diffraction analysis. An OFET device was fabricated using a spin-coated film of soluble 1,4,8,11,15,18,22,25-octakisbutoxy-2,3,9,10,16,17,23,24-octakis-ethynyl phenyl phthalocyaninato cobalt(ii) with a bottom-gate top-contact device configuration. The transfer and output characteristics were investigated to evaluate the charge carrier mobility. The mechanisms of the leakage current through the gate dielectric were also investigated, which revealed that the dominant leakage current mechanism is Fowler-Nordheim tunneling.

Ferrocenyl Phthalocyanine as Donor in Non-Poly(3-hexylthiophen-2,5-diyl) Bulk Heterojunction Solar Cell.

Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and environmentally benign photovoltaic devices. In this work, a BHJ solar cell was designed, based on a hexadeca-substituted phthalocyanine (FcPc) with ferrocenyl linked to the phthalocyanine ring. Next, we sought to obtain more quantitative information about the usability of this newly synthesized compound as a donor material in BHJ solar cells. Thus, BHJs with the structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/FcPc:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend/LiF/Al were fabricated and characterized. The effect of blend ratio (0.5-2.0) on the BHJ solar cell parameters was also investigated. Interesting results were obtained in FcPc and the PCBM blend-based BHJ solar cell under optimized conditions. Our results presented here demonstrate that BHJ devices employing FcPc as a donor has great potential for the development of highly efficient non-poly(3-hexylthiophen-2,5-diyl) photovoltaic devices.

Spectroscopic, electrochemical and photovoltaic properties of Pt(ii) and Pd(ii) complexes of a chelating 1,10-phenanthroline appended perylene diimide.

In this study, a bis-chelating bridging perylene diimide ditopic ligand, namely N,N'-di(1,10-phenanthroline)-1,6,7,12-tetrakis-(4-methoxyphenoxy)perylene tetracarboxylic acid diimide (1), was synthesized and characterized. Further reactions of 1 with d8 metal ions such as Pt(ii) and Pd(ii) having preferential square-planar geometry afforded the novel triads [(Cl2)M(ii)-(1)-M(ii)(Cl2)] where M(ii) = Pt(ii) (2), and Pd(ii) (3), respectively. The isolated triads and the key precursor were fully characterized by FT-IR, 1D-NMR (1H NMR and 13C DEPT NMR), 2D-NMR (1H-1H COSY, 1H-13C HSQC, 1H-13C HMBC), MALDI-TOF mass and UV/Vis spectroscopy. The electrochemical properties of 1, 2 and 3 were investigated by cyclic voltammetry as well as in situ spectroelectrochemistry and also in situ electrocolorimetric measurements. These compounds were shown to exhibit net colour changes suitable for electrochromic applications. The compounds exhibited remarkably narrow HOMO-LUMO gaps, leading to their ease of reduction at low negative potentials. More importantly, dye-sensitized solar cells (DSSCs) were also fabricated using 1-3 to clarify the potential use of these complexes as a sensitizer. Analysis of the experimental data indicated that 2 has good potential as a sensitizer material for DSSCs.

o-Carborane, Ferrocene, and Phthalocyanine Triad for High-Mobility Organic Field-Effect Transistors.

An unsymmetrical zinc phthalocyanine with ferrocenylcarborane linked to the phthalocyanine ring through a phenylethynyl spacer was designed for organic field-effect transistor (OFET). The unsymmetrical phthalocyanine derivatives were characterized using a wide range of spectroscopic and electrochemical methods. In particular, the ferrocenylcarborane structure was unambiguously revealed based on the single-crystal X-ray diffraction analysis. In-depth investigations of the electrochemical properties demonstrated that the ferrocenylcarborane insertion extended the electrochemical character of ferrocenylcarborane-substituted phthalocyanine (7). Moreover, in the anodic potential scans, the oxidative electropolymerization of etynylphthalocyanine (6) and 7 was recorded. To clarify the effect of the insertion of ferrocenylcarborane (2) on the field-effect mobility, solution-processed films of 2, 6, and 7 were used as an active layer to fabricate the bottom-gate top-contact OFET devices. An analysis of the output and transfer characteristics of the fabricated devices indicated that the phthalocyanine derivative functionalized with ferrocenylcarborane moiety has great potential in the production of high-mobility OFET.

Bridged oxide nanowire device fabrication using single step metal catalyst free thermal evaporation.

In this study, indium-tin-zinc-oxide (ITZO) and Zn doped In2O3 nanowires were directly grown as bridged nanowires between two heavily doped silicon (Si) electrodes on an SOI wafer using single step vapor-solid-solid (VSS) growth method. SEM analysis showed highly dense and self aligned nanowire formation between the Si electrodes. Electrical and UV response measurements were performed in ambient condition. Current-voltage characteristics of devices exhibited both linear and non-linear behavior. This was the first demonstration of bridged ITZO and Zn-doped In2O3 nanowires. Our results show that bridged nanowire growth technique can be a potential candidate for high performance electronic and optoelectronic devices.

Microwave-assisted synthesis of novel non-peripherally substituted metallophthalocyanines and their sensing behaviour for a broad range of Lewis bases.

The synthesis of novel, symmetrical, tetrasubstituted metallophthalocyanines (cobalt, zinc, and manganese) bearing four 2-(4-methyl-1,3-thiazol-5-yl)ethoxy units is reported. The new compounds have been characterized using UV-Vis, IR, (1)H NMR, (13)C NMR, and mass spectroscopy data. Photophysical properties of zinc(ii) phthalocyanines were found, including electronic absorption and fluorescence quantum yields. The fluorescence of the complexes was investigated in DMF and it was found that benzoquinone (BQ) was an effective quencher. The response and recovery behaviours of the spin coated films to different analytes, which span a broad range of Lewis bases, have been investigated by means of conductivity measurements. It was observed that the operating temperature had a considerable effect on the gas sensing performance of the sensors investigated. The sensing behaviour of the films for a broad range of Lewis bases and the correlation between the sensor sensitivity and Lewis base enthalpies were investigated. Results show that the sensitivity of the films may be correlated exponentially with the binding enthalpy.

Synthesis, characterization and gas sensing properties of novel homo and hetero dinuclear ball-type phthalocyanines.

New ball-type homodinuclear Co(ii)-Co(ii) phthalocyanine () and ball-type heterodinuclear Co(ii)-Fe(ii) phthalocyanine () were synthesized from the corresponding [2,10,16,24-tetrakis{4,4'-cyclohexylidenebis(2-cyclohexyphenoxyphthalonitrile)}phthalocyaninatocobalt(ii)] (). The novel compounds have been characterized by elemental analysis, IR, UV-Vis and MALDI-TOF mass spectroscopy. Gas sensing capability of the spin coated film of and were studied using amperometric technique at various temperatures. For a better understanding of the interaction of and films with organic compounds, two different groups of compounds (aromatics and alcohols) were selected as test analytes. It was observed that the operating temperature had a considerable effect on the gas sensing performance of the sensors investigated. The experimental results show that film offers a promising perspective as a sensing material for the detection of relatively low aromatic vapours even at room temperature. This suggests that aromatics might be distinguished from alcohols. The obtained data were analysed using two different adsorption kinetic models: the pseudo first order equation and Elovich equation to determine the best fit equation for the adsorption of toluene vapor onto and films. The first-order equation was the best of the various kinetic models studied to describe the adsorption kinetic of toluene on Pc films at higher concentrations, as evidenced by the highest correlation coefficients. In addition, it was observed that Elovich equation generates a straight line that best fit to the data of adsorption of lower concentrations of toluene.

Gas sensing and electrochemical properties of tetra and octa 2H-chromen-2-one substituted iron(II) phthalocyanines.

The synthesis of novel alpha tetra, beta tetra and beta octa 4-(4-methoxyphenyl)-8-methyl-coumarin-7-oxy, and beta octa 4-chloro-5-(4-(4-methoxyphenyl)-8-methylcoumarin-7-oxy) substituted iron(II) phthalocyanines has been achieved by the reaction of the corresponding phthalonitriles with iron(II) acetate. The compounds were characterized by elemental analysis, FT-IR, UV-vis, and MALDI-TOF mass spectrometry. The reduction and oxidation properties of the compounds were identified by voltammetric and in situ spectroelectrochemical measurements. The gas sensing behavior of the spin coated films of the differently substituted iron(II) complexes towards CO2, CO and SO2 was investigated at various temperatures between 300 K and 500 K. While exposure to SO2 had no considerable influence on the sensor current, the presence of CO and CO2 gases led to a large increase in sensor currents. The effect of relative humidity on the CO and CO2 sensing capability of the spin coated films was also studied. The results showed that the presence of water vapor, acting as an interference gas, causes a decrease in the CO2 sensitivity, but an increase in the CO sensitivity of the sensors. The experimental adsorption data were analyzed using the Elovich kinetic model. Linear regression analysis results show that the Elovich equation provides the best correlation for the CO2 and CO adsorption processes under humid conditions. However, the experimental data deviated considerably from the theoretical model under a dry atmosphere.

A conformationally stressed novel ball-type perylenediimide appended zinc(II)phthalocyanine hybrid: spectroelectrochemical, electrocolorimetric and photovoltaic properties.

A supramolecule, 6, based on an electron-donor zinc phthalocyanine (ZnPc) and an electron-acceptor perylene diimide (PDI) has been synthesized and characterized by elemental analysis, UV/Vis, IR, (1)H NMR and solid state (13)C CPMAS NMR and also MALDI-TOF and ICP mass spectrometry. The PDI appended ZnPc core brings about a geometrical constraint in the molecule with intriguing spectroscopic, electrochemical and photovoltaic properties. The first reduction process of 6 occurs on the PDI core while the first oxidation takes place on the Pc ring. These processes reflect a considerably small HOMO-LUMO gap of 1.50 eV, which has vital importance for optoelectronic applications. In addition, the PDI-based first and second reduction processes of 6 are accompanied by an electrochromic behaviour with colour changes from dark purple to blue and blue to turquoise, respectively. A photovoltaic cell involving 6 as the donor and [6,6]-phenyl C61 butyric acid methyl ester as the acceptor has been fabricated. The measurements of the effect of annealing temperature on its performance indicated that the annealing process gives rise to a significant increase in the open circuit voltage, the fill factor and the photoconversion efficiency.

Dielectric properties and electronic absorption: a comparison of novel azo- and oxo-bridged phthalocyanines.

The novel two homologous phthalocyanine (Pc) series (azo- and oxo-bridged) substituted with a 5-bromo-2-methoxyphenyl moiety were synthesized and characterized. The physical and chemical properties of the Pcs were compared with each other for the first time. The ac response of the Pcs was also studied by impedance measurements over a temperature range of 300-500 K. The real and imaginary parts of the impedance were found to be dependent on both frequency and temperature. The impedance spectra of the samples displayed semicircular arcs in the complex plane plot at all temperatures, with their centres lying below the real axis at a particular angle of depression indicating the distribution of relaxation times. Measurements showed that the dielectric permittivity of azo-bridged phthalocyanines is significantly higher than that of the oxo-bridged homologs. This result can be attributed to the limited electron delocalization ability of oxo-bridged homologs.

Coumarin-substituted manganese phthalocyanines: synthesis, characterization, photovoltaic behaviour, spectral and electrochemical properties.

The synthesis and spectroscopic characterization of novel manganese(III) phthalocyanines bearing 7-oxy-4-(4-methoxyphenyl)-8-methylcoumarin or/and chloro groups have been achieved. The effect of alpha and beta substitution on the ligand- and metal-based reduction processes of the manganese phthalocyanine complexes and their interaction with dioxygen were investigated. The more effective interaction of the central metal of the beta coumarin substituted complex with dioxygen than that of its alpha substituted analogue was attributed to the hindrance of the interaction by the nonplanarity in the case of alpha substitution. Similarly, the aggregation tendency was lower in the case of alpha substitution. Among the fabricated coumarin-substituted manganese phthalocyanine donor layer and fullerene (C60) acceptor based photovoltaic heterojunction devices, the one containing 8 exhibited the best performance. The effect of the thickness of the active Pc layer on solar cell parameters has also been investigated. A nearly thickness independent open circuit voltage was observed.

Synthesis, characterization, oxygen electrocatalysis and OFET properties of novel mono- and ball-type metallophthalocyanines.

Novel mono- and ball-type Co(ii), Zn(ii) and Cu(ii) metallophthalocyanines (MPcs) were synthesized from 1,1'-p-anisylidenbis(2-naphthoxyphthalonitrile). The MPcs have been characterized by elemental analysis, UV/Vis, IR and (1)H-NMR spectroscopy and MALDI-TOF mass spectrometry. The performances of organic field effect transistors (OFETs) of the dinuclear ball-type MPcs have been compared to those of mononuclear counterparts. The ball-type MPc based OFETs showed a p-channel and typical ambipolar transport properties. On the other hand, it was not possible to measure the full transfer characteristics of the mononuclear MPc based devices. The best results were obtained in the case of dinuclear Cu2Pc2. In this case, the mobility value is µ = 4.4 × 10(-2) cm(2) V(-1) s(-1) and the threshold voltage is 27.6 volts. The reduction and oxidation characteristics of the mono-nuclear and ball-type MPcs have been compared by cyclic voltammetry, square wave voltammetry and controlled potential coulometry on platinum in nonaqueous media. The comparison suggested that the ball-type complexes form ring-based and/or metal-based mixed-valence species as a result of the remarkable interaction between the two Pc rings and/or metal centers. The stability of these species was confirmed by the mixed-valence splitting values for the complexes. The electrocatalytic performances of the mononuclear and dinuclear complexes for the oxygen reduction reaction were also studied. The compounds involving Co(ii) at the phthalocyanine core, especially the ball-type one, showed much higher catalytic performances towards oxygen reduction than those of the other ones.

Synthesis, characterization, OFET and electrochemical properties of novel dimeric metallophthalocyanines.

The synthesis of 4,4'-[6,6'-methylenebis (2-(2-(3,4-dicyanophenoxy)-5-methylbenzyl)-4-methyl-6,1-phenylene)] bis (oxy) diphthalonitrile 1 was achieved starting from 4-nitrophthalonitrile and 6,6'-methylenebis(2-(2-hydroxy-5-methylbenzyl)-4-methylphenol in DMF at 50 °C by the catalysis of K2CO3 under argon. The corresponding dimeric metallophthalocyanines (Zn2Pc2 2 and Co2Pc2 3) were tetramerized in dimethylaminoethanol with the appropriate metal salt. Newly synthesized compounds were characterized by elemental analysis, UV-vis, FT-IR (ATR), MALDI-TOF mass and (1)H-NMR spectroscopy techniques. The electrochemical properties of the complexes were examined by cyclic voltammetry, differential pulse voltammetry, controlled potential coulometry and in situ spectroelectrochemistry in nonaqueous media. The results showed that while there is considerable weak interactions between the two metal phthalocyanine units in dimeric zinc phthalocyanine, these interactions in dimeric cobalt phthalocyanine is remarkable. The catalytic performances of dimeric cobalt phthalocyanine in the reduction of oxygen in a medium similar to the working conditions of the polymer electrolyte membrane fuel-cells were found to be much higher than that of dinuclear zinc phthalocyanine. Solution-processed films of the complexes were utilized as an active semiconducting layer in the fabrication of organic field-effect transistors (OFETs) in the bottom-gate configurations. The output characteristics of the resulting p-type OFET devices were investigated to evaluate the performances such as the field effect mobility (µF). A relatively high field effect mobility of 7.3 × 10(-3) cm(2) V(-1) s(-1) was observed for dimeric cobalt phthalocyanine.

Synthesis, interface (Au/M2Pc2/p-Si), electrochemical and electrocatalytic properties of novel ball-type phthalocyanines.

The phthalodinitrile derivative (3) was prepared by the reaction of 4,4'-(octahydro-4,7-methano-5H-inden-5-ylidene)bisphenol (1) and 4-nitrophthalonitrile (2) with dry DMF as the solvent in the presence of the base K(2)CO(3) by the method of nucleophilic substitution of an activated nitro group in an aromatic ring. The template reaction of 3 with the corresponding metal salts gave the novel bi-nuclear ball-type metallophthalocyanines, MPcs {M = Co (4), Cu (5), Zn (6)}. Newly synthesized compounds were characterized by elemental analysis, UV-vis, FT-IR (ATR), MALDI-TOF mass and (1)H-NMR spectroscopy techniques. The electronic spectra exhibit an intense π→π* transition of characteristic Q and B bands of the Pc core. The dielectric properties and interface between the spin coated films of 4-6 and a p-type silicon substrate have been studied by fabricating metal-insulator-semiconductor capacitors. The results indicated that the frequency dependence of the dielectric permittivity, ε'(ω), exhibits non-Debye type relaxation for all the temperatures investigated. The ac conductivity results indicated that the conduction mechanism can be explained by a hopping model at low temperatures (<430 K) and a free band conduction mechanism at high temperatures (≥430 K). The density of interface state calculations on these novel compounds showed that the combination of Au/4/p-Si is a promising structure with a high dielectric constant and a low interface trap density suitable for metal-oxide-semiconductor devices. The electrochemical properties of the Pc complexes were examined by cyclic voltammetry, differential voltammetry and controlled potential coulometry on platinum in non-aqueous media. The complexes showed ring-based and/or metal-based mixed-valence behaviours as a result of the remarkable interaction between the two Pc rings and/or metal centres. The mixed-valence splitting values for the complexes suggested that the mixed valence species are considerably stable. The Vulcan XC-72(VC)/Nafion(Nf)/4 modified glassy carbon electrode showed much a higher catalytic performance towards oxygen reduction than those of VC/Nf/5 and VC/Nf/6 modified ones.