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High performance photosensing devices have been effectively produced utilizing copper phthalocyanine (CuPc) as an organic photoactive material. The opto-electrical effects of organic semiconductor (OSC) based phototransistors are concentrated in this work. The light affectability of the thin film is examined using UV–Visible spectrometer. The current–voltage (I-V) curves with and without illumination represent that the device is highly sensitive towards illumination. The effect of illumination on the opto-electrical properties of the devices has been also investigated with constant bias voltage. The mobility of the fabricated devices could be enlarged definitely after light illumination. The fabricated device shows p-channel working with greatest carrier mobility of 0.41 ± 0.02 cm2/Vs under illumination. It was found that enhanced responsivity and an improved detectivity could be accomplished in lower intensity. The maximum responsivity and detectivity obtained from these devices were 1.14 ± 0 0.01 A/W and 4.57 ± 0.02 × 1011 Jones with 5 mW/cm2 intensity at very small bias voltage. Both high responsivity and detectivity portrayed in this study firmly suggest that CuPc based phototransistors are a good candidate for upcoming photosensitive and optoelectronic device applications.

Micallef et al. recently described in this Journal [38 (2019) 1–7] the use of crystal engineering methods to increase the opacity of terra verde (green earth) pigment for conservation inpainting purposes. In contrast to their chemical characterization of the pigment as comprising only natural inorganic minerals, this research shows that the commercial Verona green earth pigment used in their experiments contains a significant quantity of the synthetic organic pigment adulterant, copper phthalocyanine green (PG7 form). This bright green additive provides most of the color of their source pigment and is shown to be a common additive to so-called “green earth” colorants sold to artists and conservators. Their results must be reassessed in light of this oversight.

The synthetic nitroso dyestuff Acid Green 1 (hereafter AG1, C.I. 10020) and its lake (C.I. Pigment Green 12, hereafter PG12), today known under the trade name Naphthol Green B, was identified for the first time on six historical colour charts of commercial brands of artists’ paints. These comprise water and oil colours produced between 1910 and 1932 by the companies Winsor & Newton (London), G. Wagner (Hannover), Fr. Schoenfeld (Dusseldorf), Redeker & Hennis (Nurnberg) and Talens & Zoon (Apeldoorn). Because the use of AG1 (first synthesis in 1883) is well-known for textile dyeing, but not at all as a lake pigment for artists’ paints, these findings stimulated a comprehensive source research on the early production history, fastness properties and acceptance of the lakes of AG1 in the chemical and paint-technological literature from its invention to c. 1950. To summarize the findings, lakes of AG1 are regularly mentioned for paint purposes soon after the dyestuff's invention, mainly for house paints, paints for wall papers or as pigment for printing inks. In 1892, a lead lake of AG1 is described explicitly also for artists’ paints and a certain use in artists’ water colours, but also oil paints of higher quality could be proved until at least the 1930ies by the source research presented here. However, the pigment's fastness to light is unsatisfactory according to modern standards, and lakes of AG1, since 1956 denoted as PG12 (barium lake), are no longer of relevance in artists’ paints. It was presumably replaced by more stable organic green pigments such as those from the copper phthalocyanine group that have been introduced since the mid-1930ies. In this work, the non-destructive or minimally invasive analytical identification of AG1/PG12 in works of art is shown to be possible by Raman spectroscopy, SERS, FTIR and/or UV/VIS/NIR reflectance spectroscopy, accomplished by XRF for the lake substrate characterisation. Reference spectra of modern and historical specimens of AG1 (as lake and dye) produced in 1893 and 1900 are also presented here. Knowledge of the application and chronology of this today almost unknown pigment in art is of importance e.g. for dating purposes in authentication cases as well as under preventive conservation aspects, e.g. to define appropriate conditions for lightning conditions.

Organic Photodetectors have high potential for use in the next generation of information technology systems because of the mechanical flexibility, large-area detection and low production cost of organic materials for photodetectors. A red light photodetector based on phthalocyanine compounds is one of the representations. There are some disadvantages for the common methods to fabricate phthalocyanine films, such as expenses of high operation temperature, ultrahigh vacuum processing, large materials loss, complicated operation, large energy consumption and poor solubility. To solve these problems, a multiple drop casting method is proposed in this paper. This method could prepare phthalocyanine films from a relatively dilute solution, and give an alternative way to fabricate the phthalocyanine photodetectors especially for the phthalocyanine with poor solubility.

A stable chitosan protected tetrasulfonated copper phthalocyanine (Chit-TsCuPc) modified glassy carbon electrode (GCE) was used to aid the electrochemical detection of nitrite (NO2−) in food samples. The electrochemical oxidation of NO2− was investigated on bare, chitosan and TsCuPc modified GCE in presence of phosphate buffer solution with an acidic medium. The elevated oxidation peak current was noticed at less oxidation potential for + 0.55 V vs. Ag/AgCl at Chit-TsCuPc modified electrode under the optimized experimental conditions. The plot displays the peak current against NO2− with a good linearity in the concentration rangefrom 6.5 × 10−8 M to 5.0 × 10−10M. The linear regression equation is calculated to be Ip (μA) = 0.5291 + 1.4894C (NO2−), has a good correlation coefficient of 0.9949 and the detection limit of 22 nM (S/N = 3) with the current sensitivity of 4.964 μA nM−1 cm−2. The standard addition method was adopted to measure the unknown NO2− concentration in food samples.

In this work, we prepared modified copper phthalocyanine-carbon nanotube (CuPc-CNT) catalysts containing bimetallic (Au-Pt, Au/Pt, Pt/Au) and monometallic nanoparticles (Au or Pt), using a simple electrochemical technique. We investigated the catalyst structural and physical properties by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and electrochemical impedance spectroscopy. The bimetallic systems (Au-Pt/CuPc-CNT > Pt/Au/CuPc-CNT > Au/Pt/CuPc-CNT) proved to have a better current density towards methanol oxidation than that of mono-metallic systems (Pt/CuPc-CNT > Au/CuPc-CNT) in alkaline media. The electrochemical surface area (ECSA) of Au-Pt/CuPc-CNT was found to be 60.25 m(2) g(-1). The methanol oxidation reaction took place with the electron transfer, followed by the catalytic chemical reaction. Thus, the electrochemically-prepared Au-Pt/CuPc-CNT catalyst of the highest stability and enhanced electrocatalytic activity towards methanol oxidation represents a promising candidate for use in alkaline direct methanol fuel cells., Ege University Research Funds [12 FEN/039], This work was supported by Ege University Research Funds (project no: 12 FEN/039) . The author would like to thank TuBITAK-BIDEB for providing financial support during this study, which is produced from a PhD thesis study.

Bottom gate, top contact Organic Field Effect Transistors (OFETs) were fabricated using copper phthalocyanine (CuPc) as an active layer. The electrical properties of OFETs fabricated with CuPc annealed at different annealing temperatures and different channel length to width (L/W) ratios were studied. The transfer characteristics of the devices appear to improve with annealing temperature of CuPc and increasing L/W ratios of the devices. Upon annealing, the field effect mobility increased from 0.03 ± 0.004 cm2/V to 1.3 ± 0.02 cm2/V. Similarly, the interface state density reduced from 5.14 ± 0.39 × 1011 cm−2eV−1 for the device fabricated using as deposited CuPc, to 2.41 ± 0.05 × 1011 cm−2eV−1 for the device with CuPc annealed at 80 °C. The on/off current ratio increased from 102 for the as-deposited device, to 105 for the device with CuPc annealed at 80 °C. The dependence of the subthreshold swing on the L/W ratio was also investigated. Keywords: Organic field effect transistors, CuPc, Scanning tunneling microscope, Interface trap density, Carrier mobility

Flexible perovskite solar cells (PSCs) such as inverted PSCs are gaining increasing attention due to their wide range of potential applications, while the selection of stable, high conductivity and energy level suitable hole transport layers (HTLs) is still challenging. Here we introduce dopant-free copper phthalocyanine (CuPc) as HTL in inverted planar PSCs, and demonstrate improved photovoltaic performance and increased stability with high reproducibility and uniformity compared to the PEDOT:PSS based devices. The champion efficiency of PSCs is achieved by 15.4% on rigid substrates and 12.8% on flexible substrates, respectively. The flexible devices also exhibit excellent bending stability, retaining ∼85% of the original power conversion efficiency (PCE) after 3000 bending cycles at r = 5 mm without encapsulation. Our study provides a new strategy for fabricating cost-effective, scalable and flexible PSCs with high efficiency, little hysteresis, and excellent stability.

An experimental study of electronic properties, structure and morphology of Copper-phthalocyanine films deposited onto Al(100) and Au(110), as a function of thickness up to tens of nanometers, is presented. The monolayers grown on these two model substrates are already known to exhibit very different behavior for what concerns both the degree of interaction with the substrate and the formation of long range order; in this experiment, by means of low energy electron scattering and Electron Energy Loss Spectroscopy (EELS), remarkable differences are revealed also in the successive growth. Exploiting the link between the crystal structure and the lineshape of HOMO–LUMO transition in EELS spectrum, two different structural phases are identified, compatible with α and β phases, respectively in the case of the film grown on aluminum and on gold. Besides, the evolution of the specular reflection elastic peak indicates the formation of islands on the gold substrate and a more homogeneous growth on the aluminum one.

Copper phthalocyanine (CuPc)-based organic thin film transistors (OTFTs) with various thicknesses of organic semiconductor were fabricated, and the corresponding gas sensing performance was systematically evaluated. In situ measurements of OTFTs under nitrogen dioxide (NO 2 ) exposure showed a remarkable sensitivity enhancement from 7% to 241% by simply decreasing CuPc film thickness from 40 to 10 nm. CuPc films were analyzed by atomic force microscopy and grazing incidence X-ray diffraction. The results showed that thinner CuPc film, which enhances the interplay of CuPc film and NO 2 analyte, is beneficial for NO 2 diffusion and smaller CuPc grain formation, resulting in considerable sensing performance improvement.

Copper phthalocyanine (CuIIPc) was found to be an efficient catalyst for the catalyzed N-arylation of N H heterocycles with aryl iodides and bromides under mild reaction conditions. A variety of hindered and functionalized N H heterocycles and aryl halides were successfully used as the substrates for the given catalytic reaction and were transformed in good to excellent yields.

Organometal halide perovskite solar cells have been constructed using soluble tetra-n-butyl-copper phthalocyanine as hole transporting material. Devices were constructed and characterized under ambient conditions of 50–60% ambient humidity. Soluble copper phthalocyanine gave a modest PCE of 7.3% but when a buffer layer of either Al2O3 or graphene oxide was introduced between the perovskite and the hole transporting layer the cell efficiency extensively increased and reached 14.4% in the presence of graphene oxide. Corresponding data obtained by employing the standard spiro-OMeTAD as hole transporter gave equivalent performance. Combination then of tetra-n-butyl-copper phthalocyanine with graphene oxide offers a very good alternative of simpler and stable materials for perovskite solar cell construction. The presently recorded data highlight the role of the buffer layer, especially graphene oxide, as the material which blocks shunt paths and facilitates hole transfer between the perovskite and the hole transporting layer.

Hyperbilirubinemia is a systemic global problem and an often diagnosed pathology in newborns. In most cases, blue-light phototherapy (410–460 nm) is the only treatment required to prevent the bilirubin neurotoxicity, but its effectiveness is dose-dependent and is highly affected by the skills, knowledge, and attention of nurses and clinicians who implement the treatment. This paper presents a novel light-sensitive colorimetric dosimeter to simulate the effect of blue-light phototherapy on the optical properties of in vitro bilirubin. The dosimeter is based on a multilayered organic structure comprising a light-stable green-light emitter (copper phthalocyanine, C 32 Cl 16 CuN 8 ), and a blue-light-sensitive red emitter (poly{[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene]vinylene}, OC 1O C 6 -PPV). The optical and chemical properties of the dosimeter were investigated by fluorescence and FTIR spectroscopies and by color coordinates of CIE (1931) diagram chromatics, while the photochemical processing of bilirubin was evaluated by UV–vis absorption spectroscopy. The optical response of the dosimeter under conventional (10 μW/cm 2 ) and intensive (40 μW/cm 2 ) phototherapy was found to present the same photochemical kinetics as bilirubin. These findings highlight a cutting-edge solution for monitoring bilirubin elimination in neonates as a function of the dosimeter’s color evolution. This novel colorimetric dosimeter provides a standardized method of reporting and measuring phototherapy dose to promote an efficient use of available phototherapy units in health facilities.

The impact was examined of surface ordering of 50 nm-thick copper phthalocyanine (CuPc) layers on the layer's susceptibility to ambience-induced degradation processes. The surface morphology of CuPc layers obtained by physical vapor deposition with different deposition rates, 0.01 nm/s (r1) and 0.02 nm/s (r2), was diagnosed applying atomic force and scanning electron microscopes. The images exhibited compact, ordered surface topography with crystallites of homogeneous geometry for a layer with r1 while randomly distributed bigger crystallites on a rougher and more expanded surface for a layer with r2. X-ray diffraction revealed the α-form of phthalocyanine, mostly with an orientation of the a axis perpendicular to the substrate plane. Mean grain size in bulk was slightly larger for CuPc with r2. Energy dispersive X-ray spectroscopy demonstrated an increase of C/Cu and N/Cu elemental ratios compared to the expected composition for both layers but significantly more pronounced for layer with r2. Morphological features and traces of CuPc-air interaction were mirrored also in the Raman spectra. Samples with r2 exhibited an increased peak width, and their peaks were shifted compared to samples with r1, which was attributed to surface disorder. The Raman spectra exhibited the appearance of additional peaks of oxidation products indicating Csingle bondOsingle bondC, Cdouble bond; length as m-dashO and Nsingle bondO bonds, with intensities coinciding to an increased carbon and nitrogen content. More intensive peaks were recorded for layers obtained with higher deposition rate, proving their stronger susceptibility to environment-induced degradation processes. © 2017 Elsevier Ltd. All rights reserved. This is the authors' accepted and refereed manuscript to the article. Locked until January 31st 2019 due to copyright restrictions

Perovskite solar cells have been constructed under ambient conditions by using 2,2',7,7'-Tetrakis-(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (spiro-OMeTAD) mixed with a small quantity of soluble tetra-n-butyl substituted copper phthalocyanine as hole transporting material. The introduction of the phthalocyanine derivative resulted in an impressive increase of cell efficiency, which changed from 10.4% in the absence to 15.4% in the presence of phthalocyanine. This effect is related to the creation of deep traps in the hole transporting phase which block back-travelling electrons as well as to the improvement of the structural quality of the spiro-OMeTAD film in the presence of phthalocyanine. Both functionalities decrease shunt paths within the hole transporting phase resulting in increasing the fill factor and the open-circuit voltage of the cell.

A soluble Zn phthalocyanine has been synthesized by tetra-substitution with triphenyl amine. This substance is functional as hole transporting material combined with organometal halide perovskite solar cells. The efficiency was slightly increased compared with previously studied insoluble copper phthalocyanine indicating that it is possible to make fully solution processed perovskite solar cells based on phthalocyanine as hole transporter.

Carbon-based CsPbI2Br perovskite solar cell (PSC) is one of the competitive candidates for photovoltaic application owing to its outstanding thermal stability and low-cost process. However, their power conversion efficiency (PCE) is significantly lower than that of the organic-inorganic hybrid PSCs, which is mainly attributed to the serious charge recombination and undesirable hole extraction at the CsPbI2Br/carbon interface. In this work, a solution-processed dopant-free copper phthalocyanine (CuPc) derivative hole transport layer (HTL) is used to modify the CsPbI2Br/carbon interface to promote charge transport and suppress charge recombination. At the optimal CuPc derivative concentration, the modified PSC shows a champion PCE up to 11.04% with less hysteresis, which is 18% higher than that of the reference PSC. Moreover, the unsealed device with CuPc derivative exhibits a promising air and thermal stability. The improved performance results from the good energy level alignment, the reduced trap-state density, the suppressed charge recombination and excellent stability of the CuPc derivative. This work reveals the potential of using solution-processed dopant-free CuPc derivative as HTL to fabricate efficient and stable carbon-based inorganic PSCs.

The behavior of phenyl-C 61 -butyric acid methyl ester (PCBM) and copper-phthalocyanine (CuPc) on a Au(1 1 1) surface was investigated using scanning tunneling microscopy (STM). When CuPc was deposited in addition to PCBM it entered and disturbed the regularly spaced double row superstructure of the PCBM molecules. PCBM intermixed with CuPc to form a new square shaped superstructure that consisted of six to eight PCBM molecules with a CuPc molecule in its center. The intermixing of these materials that was observed indicated that they possessed an attractive interaction.

Copper phthalocyanine can effectively act as alternative small molecule hole transporting material in perovskite solar cells. In order to produce solution processed devices, a soluble copper phtalocyanine has been synthesized by n-butyl substitution and it was compared to commercially available tert-butyl substituted copper phthalocyanine. It was found that the configuration of the butyl chain plays a very important role in film conductivity and in the subsequent efficiency of solar cells, n-bytyl derivative being the most effective hole transporter. Such a result is due to the fact that n-butyl derivative allows better packing of the molecules in the film and stronger π-π interaction.

Microspot two-photon photoemission (micro-2PPE) spectroscopy has been applied to measure the lateral distribution of unoccupied levels on copper phthalocyanine (CuPc) film on HOPG. In addition to the LUMO-derived level and the image potential state (IPS) on the film, we identified the modified IPS which is stabilized by the hole localized in a molecule. We show that modified IPS is observed only on bilayer area, reflecting the localization of the hole in a molecule. The modified IPS is absent on monolayer area, because the hole strongly interacts with substrate.

Copper phthalocyanine (CuPc) blues (PB15) are largely used in art and industry as pigments. In these fields mainly three different polymorphic modifications of PB15 are employed: alpha, beta and epsilon. Differentiating among these CuPc forms can give important information for developing conservation strategy and can help in relative dating, since each form was introduced in the market in different time periods. This study focuses on the classification of Raman spectra measured using 532 nm excitation wavelength on: (i) dry pigment powders, (ii) unaged mock-ups of self-made paints, (iii) unaged commercial paints, and (iv) paints subjected to accelerated UV ageing. The ratios among integrated Raman bands are taken in consideration as features to perform Random Forest (RF). Features selection based on Gini Contrast score was carried out on the measured dataset to determine the Raman bands ratios with higher predictive power. These were used as polymorphic markers, in order to establish an easy and accessible method for the identification. Three different ratios and the presence of a characteristic vibrational band allowed the identification of the crystal modification in pigments powder as well as in unaged and aged paint films.

To improve the efficiency of polymer solar cells, a third component copper phthalocyanine (CuPc) was added into poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) binary blends, the normal and inverted ternary blend solar cells were fabricated. The results showed that the incorporation of the CuPc into P3HT:PCBM binary blends not only broadened the absorption range of solar spectrum but also improved the charge separation and transport properties. As a result, a higher short circuit current and fill factor were obtained for ternary blend devices, especially, the power conversion efficiencies (PCEs) of the ternary blend solar cells increased 19% compared with the PCEs of binary blend solar cells.

In this work, the efficiency of organic photovoltaic cells (OPV) based on copper phthalocyanine (CuPc) as donor/fullerene (C60) as an acceptor was improved via Poly(3,4-ethylene dioxythiophene):Polystyrene sulfonate (PEDOT:PSS) as (photoconductor transport layer) embedded by silver nanoparticles. Silver nanoparticles (AgNPs) were prepared using a thermochemical method. The change of the surface plasmonic band position of AgNPs has been explained by the Uv-Vis spectra. Different sizes and shapes of AgNPs have been confirmed from images of a transmission electron microscope (TEM). Thin films of PEDOT: PSS embedded by different sizes and shapes of AgNPs were made on glass/ITO using Spin Coater. The last two layers of CuPc and C60 were precipitated using a vacuum evaporation technique. The study of the prepared junction film using AFM showed a morphological smooth on the surface layers due to the good distribution of AgNPs. Cell efficiency of OPV was improved from 0.663 to 0.925 with increasing the particle sizes of AgNPs from 43 nm to 57 nm. The increase in VOC, ISC, and fill factor with increasing the particle size can be attributed to the increase in scattering light and the built-in electric field that generate due to surface plasmon resonance around AgNPs embedded in PEDOT:PSS. The scattering increases the excitons (e-h) generation and built-in electric field dissociation these excitons to e- and h+ and move to terminal connection and improved the cell efficiency.

Electrical properties of Au/n-GaN Schottky rectifier with copper pthalocyanine (CuPc) interlayer were investigated using current–voltage ( I–V ), capacitance–voltage ( C–V ) and conductance–voltage ( G–V ) characteristics. The barrier height obtained for the Au/CuPc/n-GaN Schottky diode was higher than that of the Au/n-GaN Schottky diode. This could be associated with the presence of the CuPc interlayer influencing the space-charge region of the Au/n-GaN structure. The Au/CuPc/n-GaN Schottky structure exhibits higher ideality factor, indicating the higher interface inhomogeneity in Au/CuPc/n-GaN as compared to Au/n-GaN Schottky structure. The density of interface states was extracted using I–V , C–V , and G–V characteristics. The results showed that the introduction of CuPc interlayer facilitated the reduction of interface state density ( N SS ) of Au Schottky contact to n-GaN. Particularly, the N SS obtained from frequency-dependent C–V characteristics was lower than that determined from forward I–V characteristics, which could be attributed to the inhomogeneous distribution of N SS at Schottky interface.

Heat treatment is able to cause the structural transformation of phthalocyanine thin film during the post-deposition heat treatment. The annealing effects of the process on the film characteristics of vacuum deposited copper phthalocyanine thin films were studied. However, the pre-annealing leads to a larger-grain and a more compact structure. Structure transformation was inhibited by post-deposition annealing at 300oC. Thin films of CuPc were deposited using vacuum evaporation technique method onto glass substrates. The films were annealed at 4 different temperatures (323, 333, 343 and 353 K) in air at different intervals of time. Optical studies were done and the results are discussed. The optical band gap for the film as obtained from the graph for all the thin films are tabulated and analyzed. X ray diffraction studies on the deposited film showed crystallinity with a major peak for CuPc.

A simple procedure for the preparation of microcrystals of insoluble copper phthalocyanine (CuPc) by thermolysis of a dimethoxy-substituted precursor has been developed. Although the morphologies of the resultant microcrystals are practically independent from initial solution concentrations higher than ca. 0.03 mM of the dimethoxy-precursor, crystals with increased width are obtained with increasing the initial concentration of the precursor.

Copper phthalocyanine (CuPc)-based thin film transistors were fabricated using CuPc films grown under different deposition pressure (Pdep) (ranging from 1.8 � 10 � 4 Pa to

Optical electric-field-induced second-harmonic generation measurement was employed for studying interfacial processes in copper phthalocyanine (CuPc)/C60 double-layer organic solar cells. Results suggested that interfacial charging process happened on the CuPc/C60 interface and the applied illumination can change the polarity of the accumulated charges on the double-layer interface while the direction of conduction current is the same. The Maxwell–Wagner model analysis revealed that the photo conductance change is responsible for these converse behaviors with and without illumination.

Dielectric anisotropy and electrical properties of the copper phthalocyanine (CuPc): 4–4′-n-heptylcyanobiphenyl (7CB) composite liquid crystals have been investigated. Liquid crystals exhibit dielectrically-controlled positive dielectric anisotropy (p-type Δ ɛ ) and the dielectric anisotropy changes from positive to negative dielectric anisotropy (n-type Δ ɛ ) behavior with frequency of applied electrical field. The critical frequency f c values for the 7CB and CuPc doped 7CB liquid crystals were found to be 602 kHz and 518 kHz, respectively. This indicates that CuPc doping causes a decrease in the critical frequency. The splay elastic coefficients of the 7CB and CuPc doped 7CB liquid crystals were determined and CuPc doping increases the splay elastic coefficient of 7CB liquid crystal. The 7CB liquid crystal exhibits a voltage-controlled differential negative resistance (VCNR) behavior and CuPc doping affects significantly VCNR behavior of 7CB.

In art analysis, copper phthalocyanine (CuPc) is often identified as an important pigment (PB15) in 20th century artworks. Raman spectroscopy is a very valuable technique for the detection of this pigment in paint systems. However, PB15 is used in different polymorphic forms and identification of the polymorph could retrieve information on the production process of the pigment at the moment. Raman spectroscopy, being a molecular spectroscopic method of analysis, is able to discriminate between polymorphs of crystals. However, in the case of PB15, spectral interpretation is not straightforward, and Raman data treatment requires some improvements concerning the PB15 polymorphic discrimination in paints. Here, Raman spectroscopy is combined with chemometrical analysis in order to develop a procedure allowing us to identify the PB15 crystalline structure in painted layers and in artworks. The results obtained by Linear Discriminant Analysis (LDA), using intensity ratios as variables, demonstrate the ability of this procedure to predict the crystalline structure of a PB15 pigment in unknown paint samples.

The nonlinear absorption (NLA) properties of copper phthalocyanine (CuPc) solution in acetone were investigated by the femtosecond open-aperture (OA) Z-scan technique. The reverse saturable absorption (RSA) phenomenon was observed. And the physical mechanism of RSA effect was revealed, which was originated from three-photon absorption. Moreover, the influences of concentration and excitation laser power on the NLA of CuPc solution were studied respectively. Results showed that the RSA effect increased with the increase of sample concentration and excitation laser power. It indicated that the CuPc could be a promising candidate for optical limiting material.

Para-sexiphenyl ( p -6P) ultrathin film was utilized as the modified layer to grow copper phthalocyanine (CuPc) thin film. The order of the CuPc thin-film morphology exhibits an obvious dependence on p -6P thickness. A conversion of p -6P growth mode from layer-by-layer to island growth was observed. The highest mobility of CuPc transistor based on p -6P modified layer has been obtained by 0.18 cm 2 /V s with the p -6P thickness of 2.4 molecule layer. Therefore, the thickness of modified layer plays a crucial role in thin film growth of organic semiconductor that results in a remarkable influence on the electric characteristics of devices.

Poly(arylene ether nitriles)/copper phthalocyanine (PEN/CuPc) functional nanohybrid films with high dielectric permittivity (140 at 100 Hz) were prepared by a solution-casting method. These films can be employed with giant dielectric permittivity copper tetra-amine phthalocyanines as a functional organic filler and acid-contained poly(arylene ether nitriles) as a polymer matrix. Dielectric properties of the PEN/CuPc showed that the nanohybrid films exhibited significant increase in dielectric permittivity by adding CuPc in polymer resin. Meanwhile, dielectric loss of the films was drastically decreased after heat treated at high temperature and the dielectric dispersion of the films became smaller. These results indicate that chemical interaction has an obvious effect on the dielectric property of the nanohybrid films.

Bottom contact organic thin film transistors (OTFTs) using SiO2 dielectric layer deposited on silicon wafer were fabricated for the gas sensor application. Copper phthalocyanine (CuPc) was used as an active layer of OTFT device to test current–voltage characteristics and gas-sensing properties of the device. When the device was exposed to the atmosphere of hydrogen sulfide (H2S) at room temperature, the source–drain current changed within a few minutes at the appropriate gate voltage and drain voltage. The dependence of sensing properties on the thickness of the insulator layer was investigated. The results showed that the device with an insulator layer of 195 nm exhibited the optimum electronic and sensing properties comparing with other devices based on the insulator layer of 125 nm and 300 nm.

The copper phthalocyanine (CuPc thicknesses ∼80 nm, ∼100 nm and ∼200 nm) covered with ultra thin palladium layer (Pd thickness about 18 nm) has been studied in aspect of their application as bi-layer hydrogen gas-sensing nanostructures. The studies have been performed at low operating temperature range (30–38 °C). The investigated bi-layered structures were obtained by physical vapour deposition under vacuum conditions with application of LiNbO 3 (Y- cut Z-propagating) and glass substrates. Then, the samples were tested by means of the surface acoustic wave and resistance methods. In order to characterize the surface topography the Atomic Force Microscopy has been applied. The characteristic frequency shifts have been observed after exposition to hydrogen. The absolute response value has been found to be dependent on the CuPc film thickness, the interaction temperature, hydrogen gas concentration. Investigations showed also that the bi-layer nanostructure with a 200 nm of CuPc is the most sensitive one. However, at the investigated interaction temperature ∼38 °C, the sensor characteristics are closest to linear dependence for the nanostructure with the 100 nm of CuPc. The simultaneously performed monitoring of the resistance and frequency changes provided observation of the acoustoelectric effect for the investigated nanostructures. The best sensitivity has been observed for the bi-layer structure with 100 nm of CuPc, which is characterized by the acoustoelectric parameter closest to 1.

Organic semiconductor materials are becoming a promising subject of not only scientific interest but also potential applications in the field of new energy resources. In this study, the copper phthalocyanine (CuPc) films as an excellent organic semiconductor were self-assembly grown on indium tin oxide glass by electrodeposition, the structural and electronic properties were investigated using various techniques. The results demonstrated that ordered α-form crystalline CuPc films were obtained. The decrease of electron work function of CuPc films with the increase of film thickness was found, which was obviously dependent on the surface morphology. The understanding of these behaviors of CuPc films will be significant for designing related photoelectric devices.

Spin-coating films of tetra-(tert-butyl)-5,10,15,20-tetraazaporphyrin copper (CuTAP(t-Bu)4) and tetra-(tert-butyl) phthalocyanine copper (CuPc(t-Bu)4) was obtained and characterized by absorption spectra and atomic force microscopy. The gas sensing behaviors of the films were investigated with respect to NH3 and NO2 at room temperature. In addition, the interactions between complexes and gas analytes were also discussed. It was found that the devices exhibited better response and slow response–recovery times with increase of interactions between the complexes and analytes related with conjugated ability of complexes. This suggests that the response may imparted by use of strong interactions between the complexes and the analyte of interest at the expense of reversibility.

The evolutions of the electronic structure in Cs-doped copper-phthalocyanine (CuPc) on different metal substrates have been investigated with photoemission spectroscopy. As the Cs doping ratio increases, the Fermi level of the system starts to shift towards the lowest unoccupied molecular orbital (LUMO) of CuPc, and then becomes saturated, as it aligns with the LUMO. The shift of all the energy levels has a linear dependence on the logarithm of the Cs doping ratio, with a slope of about 0.13 eV. By comparing the results of the samples deposited on different metal substrates, we found out that this slope indicates the broadening of the LUMO induced by alkali metal doping and is independent of the workfunction of the metal substrate.

Organic heterojunction thin-film transistors are fabricated based on copper phthalocyanine (CuPc) and hexadecafluorophtholocyaninatocopper (F16CuPc) as double active layers, which exhibit typical ambipolar conduction. Several substrate temperatures are utilized to tune film morphology, which results in a remarkable change on the electric characteristics of organic transistors. The highest balanced mobility value of 2.91 × 10−2 cm2/V s for hole and 1.04 × 10−2 cm2/V s for electron are obtained by depositing F16CuPc at 150 °C and CuPc at 200 °C, respectively, which are comparable to those conventional single-layer devices. This result demonstrates that the growth conditions of organic heterojunctions play a crucial role in ambipolar devices.

Bottom-contact (BC) copper phthalocyanine (CuPc) thin film transistor with UV/ozone treated Au as a source/drain electrode was fabricated and the contact resistance was estimated from the transmission line method (TLM). Comparing the properties of OTFT with untreated Au electrode, the performance of the BC CuPc-TFT with the UV/ozone treated Au electrodes was significantly improved: saturation mobility increased from 4.69 × 10−3 to 2.37 × 10−2 cm2/V s, threshold voltage reduced from −29.1 to −6.4 V, and threshold swing varied from 5.08 to 2.25 V/decade. The contact resistance of the device with UV/ozone treated Au electrodes was nearly 20 times smaller than that of the device with untreated Au electrodes at the gate voltage of −20 V. This result indicated that using the UV/ozone treated Au electrode is an effective method to reduce the contact resistance. The present BC configuration with UV/ozone treated Au electrodes could be a significant step towards the commercialization of OTFT technology.

WOS: 000280381600025, Copper phthalocyanine (CuPc) organic thin-film transistor (OTFT) was fabricated by thermal evaporation deposition on p-SiO2 dielectric layer. Organic thin-film transistors used in large display areas need the enhancement of transistor performances by increasing the I-on/I-off ratio and the mobility. The output and transfer characteristics of CuPc-OTFF having source/drain interdigitated-finger geometry were investigated. The mobility, I-on/I-off ratio and inverse sub-threshold slope for the CuPc-OTFT were found to be 5.32 x 10(-3) cm(2) V-1 s(-1), 1.94 x 10(4) and 2.5 V/decade, respectively. The interface state density of the transistor was found to be 3.73 x 10(11) eV(-1) cm(-2) using the conductance-frequency method. The CuPc film indicated a homogeneous surface having 3.878 nm small roughness values as observed by atomic force microscope (AFM) measurements. The obtained results indicate that we have improved a CuPc-OTFT transistor with high mobility without being of any substrate treatment, Feyzi AKKAYA Scientific Activates Supporting Fund (FABED); National Boron Research Institute (BOREN) [BOREN-2009.C0226]; Anadolu University Commission of Scientific Research [204, 061039], This work was supported by Feyzi AKKAYA Scientific Activates Supporting Fund (FABED). One of author wishes to thank FABED for young scientist grant. Also, this work was partially supported by the National Boron Research Institute (BOREN) (Project Number: BOREN-2009.C0226) and Anadolu University Commission of Scientific Research Projects 204 under grant no. 061039. Authors wish to thank BOREN and Anadolu 205 University.

Optimization of photo-Fenton degradation of copper phthalocyanine blue was achieved by response surface methodology (RSM) constructed with the aid of a sequential injection analysis (SIA) system coupled to a homemade photo-reactor. Highest degradation percentage was obtained at the following conditions [H 2 O 2 ]/[phthalocyanine] = 7, [H 2 O 2 ]/[FeSO 4 ] = 10, pH = 2.5, and stopped flow time in the photo reactor = 30 s. The SIA system was designed to prepare a monosegment containing the reagents and sample, to pump it toward the photo-reactor for the specified time and send the products to a flow-through spectrophotometer for monitoring the color reduction of the dye. Changes in parameters such as reagent molar ratios, residence time and pH were made by modifications in the software commanding the SI system, without the need for physical reconfiguration of reagents around the selection valve. The proposed procedure and system fed the statistical program with degradation data for fast construction of response surface plots. After optimization, 97% of the dye was degraded.

In organic thin film transistors (OTFTs), mobility generally exhibits field-effect dependence, and is strongly related to the disorder property of organic semiconductors used in OTFTs. Here, we compared three typical field-effect mobility models and used them to simulate the output characteristics of pentacene-based OTFTs. From the comparison of the theory and experiment, an analytic expression for the field-effect mobility to exactly describe the electrical characteristics of OTFTs was obtained. The better fit to the output characteristics of poly(9,9-dioctyl-fluorene-co-N-(4-butylphenyl)-diphenylamine) (TFB)-based OTFT and copper phthalocyanine (CuPc)-based OTFT by using the obtained analytic expression of the field-effect mobility further extended its applicability in OTFTs. This supplies a valuable manner to derive the field-effect mobility of carriers and understand the transport characteristics of carriers in OTFTs.

The high temperature limit of hole mobility (μ∞) in N,N′-diphenyl-N,N′-bis(1-naphthyl)(1,1′-biphenyl)-4,4′diamine (NPB) has been studied by time-of-flight technique. The effect of dopants on μ∞ was also investigated. It was found that the μ∞ is independent of the nature of dopants. The common μ∞ can be applied to estimate the full temperature dependence of zero-field mobility (μ0), if μ0 at one temperature is known. We demonstrate this concept by predicting the room temperature μ0 of NPB-doped with copper phthalocyanine (CuPc). The mobility prediction of CuPc-doped-NPB was then verified by the classic work of Hoesterey and Letson [D.C. Hoesterey, G.M. Letson, J. Phys. Chem. Solids 24 (1963) 1609].

Copper phthalocyanine (CuPc) thin films have been deposited by glow discharge-induced sublimation (GDS). This physical technique allows to produce very high porosity films, whose response to gases is much more intense than evaporated films. It has been found that both electrical and optical properties of these films change upon gas exposure due to the gas/film interaction. Electrical response of the films has been tested by exposing the samples to NO x -containing atmospheres and by measuring the slope of the electrical surface current versus gas concentration. This way NO 2 and NO concentrations down to 0.1 ppm and 10 ppm have been measured, respectively, with response times shorter than 2 min. Optical responses have been tested by measuring the change of light reflectance at a fixed wavelength upon exposure to ethanol-containing atmospheres down to concentrations of few thousands of ppm. Response times of less than 10 s have been obtained.

We investigate the spectrum of copper phthalocyanine (CuPc) both experimentally and theoretically, which is a potential laser protective organic absorbing dye. The observed visible absorption maximum is located at 658 nm, which corresponds to a 1u →e g electronic transition. We then theoretically investigate the electronic spectrum of CuPc. By setting OWF π–π (π–π overlap weighting factor, one of the adjustable parameters in the ZINDO/S method) at 0.522, the visible absorption maximum of CuPc is precisely calculated using the ZINDO/S method. The result shows that the calculated visible absorption maximum is well consistent with the experimental value. Finally, we discuss the validity and applicability of Yuan's calculation formula [J. Phys. Chem. A 109 (2005) 2582], and investigate the new relationship between OWF π–π and molecular structural parameters for the other metal phthlocyanine series.

Low temperature scanning tunneling microscopy (LT-STM) and scanning tunneling spectroscopy (STS) have been used to investigate adsorbed copper phthalocyanine (C32H16N8Cu) molecules on an ordered ultrathin Al2O3 film on the Ni3Al(111) surface as a function of coverage and annealing temperature. For sub-monolayer coverage and a deposition temperature of 140 K two different planar molecular adsorption configurations rotated by 30° with respect to each other were observed with submolecular resolution in the STM images. The template effect of the underlying oxide film on the CuPc orientation, however, is only weak and negligible at higher coverages. For θ CuPc ≈ 1 ML, before completion of the first layer, the growth of a second layer was already observed. The measured spacing of 3.5 Å between first and second layer corresponds to the distance between the layers in the greek small letter alpha-modification of crystalline CuPc. The molecules deposited at 140 K are thermally stable upon prolonged annealing to temperatures up to 250 K. By the use of STS the lowest unoccupied molecular orbital (LUMO) of the adsorbed copper phthalocyanine molecules has been identified at an energy of 1.2 eV above EF. The lateral distribution of the electronic states of the CuPc has been analyzed and mapped by STS.

The electronic structure modifications of copper phthalocyanine (CuPc) induced by interactions with Na are investigated with X-ray and ultraviolet photoemission spectroscopy (XPS and UPS). The initial Na doping induces energy level shift, which has a linear dependence in the semi-log plot. For high doping ratios, the shifts of the energy levels diverge from each other. A detailed analysis of the core levels indicates that the doped Na ions tend to interact first with the Pc orbital around the N atoms. However, as the doping ratio increases, strong chemical reactions take place, involving transitions from Cu II to Cu I .

Infrared absorption spectra of copper phthalocyanine in KBr pellet and pyridine solution in 400-1625 and 2900-3200 cm(-1)regions are reported. In the IR spectra of solid sample, presence of weak bands, which are forbidden according to the selection rules of D4h point group, is explained on the basis of distortion in the copper phthalocyanine molecule caused by the crystal packing effects. Observation of a new band at 1511 cm(-1) and change in intensity of some other bands in pyridine are interpreted on the basis of coordination of the solvent molecule with the central copper ion.

A novel, solvothermal method for directly growing crystals of the β-form of copper phthalocyanine that involved using quinoline as solvent and cooling the reaction mixture to room temperature is proposed. Needle-like, single crystals of CuPc up to 10 mm in length were prepared using 1,3-diiminoisoindoline and Cu(AcO)2·2H2O in the quinoline solvent. The influence of the temperatures, growth time and solvent volumes on crystal yield were determined.