Chloroindium Phthalocyanine Research Articles

Nonlinear properties of chloroindium phthalocyanines with nanosecond pulses

In this work we presented the study on nonlinear dynamics of tetra-α-(2-ethylbutoxy) chloroindium phthalocyanine (α-InPcCl) and tetra-β-(2-ethylbutoxy) chloroindium phthalocyanine (β-InPcCl). We replaced the electronic structure of molecules with the five-level model, and solved two-dimensional paraxial field equation and rate equations by Crank-Nicholson numerical method. The main passageway of photon absorption for optical limiting is the sequential (singlet-singlet) × (triplet-triplet) two-photon absorption. Both phthalocyanines showed distinctive optical limiting behaviors with a 532 nm–7 ns nanosecond laser. α-InPcCl shows better optical limiting effect, and we took it as an example to studied the optical dynamics in detail.

Study of Structural, Optical and AC Electrical Properties of Chloroindium Phthalocyanine

The present study aimed to investigate the AC electrical properties of chloroindium phthalocyanine (ClInPc) in order to evaluate its conduction mechanism. For this purpose, sandwich devices of ClInPc with aluminum electrodes (Al/ClInPc/Al) were fabricated. The measurements indicated that the capacitance and loss factor increased by an increase in the temperature and decreased by an increase in the frequency. In addition, measurement results obtained are consistent with Goswami and Goswami’s model. AC conductivity is confirmed by the equation σ(ω) = AωS, which is commonly used for charge transport with hopping or tunneling mechanism. In this study, the conduction mechanism was studied with correlated barrier hopping at the frequency range of 100 Hz–1 kHz and overlapping large-polaron tunneling models at the frequency range of 1 kHz–100 kHz. Furthermore, the activation energies of the device were achieved as a function of frequency. The structure of the ClInPc thin film was determined by x-ray diffraction and scanning electron microscopy images. Additionally, by using the UV analysis of the ClInPc thin film, the optical band gap was obtained as 2.9 eV and the absorption bands Q and B were observed in the visible region.

High Photosensitized Singlet Oxygen Generating Zinc and Chloroindium Phthalocyanines Bearing (4‐isopropylbenzyl)oxy Groups as Potential Agents for Photophysicochemical Applications

AbstractIn this study, novel phthalonitrile derivatives (1 and 2) and their peripherally and non‐peripherally tetra (4‐isopropylbenzyl)oxy‐substituted zinc and chloroindium phthalocyanine complexes (3‐6) have been prepared for the first time. The synthesized phthalonitrile derivatives and phthalocyanine complexes were characterized spectroscopically. Not only the chloroindium phthalocyanines but also zinc phthalocyanines are essentially free from aggregation in THF at the studied micromolar concentration. The purpose is to compare the effects of two types of substitution on the phthalocyanines to be used as sensitizers in photodynamic therapy (PDT). Photophysical and photochemical properties of all phthalocyanines are investigated and the results showed that the peripheral phthalocyanines more effectively photooxidize DPBF through singlet oxygen. The photochemical results showed that both ZnPc (3 and 5) and InPc (4 and 6) can be used as sensitizers in PDT because of their very high singlet oxygen quantum yields (range from 0.80 to 0.97).

Nonlinear transmission properties of chloroindium phthalocyanines for picosecond pulse trains

We studied the optical dynamics and propagating properties of two chloroindium phthalocyanines with α- and β-alkoxyl substituents interacting with picosecond pulse trains. The pulse train contains 35 picosecond subpulses with 12 ns spacing, and the width of each subpulse is 100 ps. We applied a five-level model to simulate the interaction by solving two-dimensional paraxial field equation coupled with rate equations. Photophysical parameters of molecules are extracted from the experiment and we employed Crank–Nicholson numerical method to get accurate and credible results. The sequential (singlet-singlet) × (triplet-triplet) two-photon absorption is the vital optical limiting channel for long pulse trains. Our work indicates that chloroindium phthalocyanine with β-alkoxyl substituent shows better optical limiting behaviors for picosecond pulse trains, which is opposite with the result for one single nanosecond laser.

Zinc and chloroindium complexes of furan-2-ylmethoxy substituted phthalocyanines: Preparation and investigation of aggregation, singlet oxygen generation, antioxidant and antimicrobial properties

The synthesis, characterization, aggregation, photophysical, antioxidant and antimicrobial properties of furan-2-ylmethoxy substituted zinc (2) and chloroindium (3) phthalocyanine complexes are reported for the first time. The novel compounds have been characterized by using elemental analysis, UV–vis, FT-IR, 1H-NMR and MS spectroscopic data. In photophysical studies, the effect of the central metal ion on the UV–vis and photophysical properties of the metallophthalocyanines are reported. These results suggest that the metal in the core of the phthalocyanine plays essential role in the fluorescence quantum yields (ΦF) of the synthesized complexes. In addition, high quantum yields of singlet oxygen generation (ΦΔ ranging from 0.58 to 0.69 in THF) were obtained. Antioxidant activities of the complexes were determined by using three different methods. In all experiments performed, complex 3 showed better antioxidant activity than complex 2. Complex 3 showed 59.01 ± 1.23% inhibition of DPPH (1,1-diphenyl-2-picrylhydrazyl) free radicals and 84.16 ± 0.13% ferrous metal chelating activity both at 500 mg/L concentration and the highest reducing power activity were measured at 0.397 nm with 80 mg/L concentration. Inhibition zone of complex 3 was found as 11 mm for Escherichia coli, 7.5 mm for Bacillus subtilis, 13 mm for Bacillus cereus and 9 mm for Pseudomonas aeruginosa. Inhibition zone of complex 2 was found 8 mm for Staphylococcus aureus and Bacillus subtilis (ATCC 6051). In addition, MIC (Minimum Inhibitory Concentrations) values varied in the range of 2.0–64 μg/mL.

Zinc(II) and chloroindium(III) phthalocyanines bearing ethyl 7-oxy-6-chloro-4-methylcoumarin-3-propanoate groups: Synthesis, characterization and investigation of their photophysicochemical properties

In this study, ethyl 7-hydroxy-6-chloro-4-methylcoumarin-3-propanoate (1), ethyl 7-(2,3-dicyanophenoxy)-6-chloro-4-methylcoumarin-3-propanoate (2), ethyl 7-(3,4-dicyanophenoxy)-6-chloro-4-methylcoumarin-3-propanoate (3), ethyl 4-chloro-5-(7-oxy-6-chloro-4-methylcoumarin-3-propanoate)phthalonitrile (4) were synthesized. The phthalonitrile derivatives (2, 3 and 4) were converted to their peripheral tetra, non-peripheral tetra and peripheral chlorocta substituted zinc(II) and chloroindium phthalocyanine derivatives. All novel compounds were characterized by elemental analysis, FT-IR, [Formula: see text]H-NMR, MALDI-TOF mass spectrometry and UV-vis spectral data. Additionally, the spectral, photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation under light irradiation) properties of the resulting substituted phthalocyaninatozinc(II) and indium(III) chloride complexes (5–10) were investigated in DMF, and the obtained results were compared for determination of the effects of the substituents’ positions and the variety of the central metal atom on these properties. The fluorescence quenching behavior of these phthalocyanines (5–10) were also investigated using 1,4-benzoquinone as a quencher. The obtained ethyl 7-oxy-6-chloro-4-methylcoumarin-3-propanoate bearing phthalocyaninatozinc(II) (5, 7 and 9) and indium(III) chloride (6, 8 and 10) complexes showed excellent solubility in most organic solvents. They produced high singlet-oxygen and showed appropriate photodegradation which is very important for photodynamic therapy applications.

Indium(III) phthalocyanine eka-conjugated polymer as high-performance optical limiter upon nanosecond laser irradiation

A novel chloroindium(III) phthalocyanine network polymer (4) was prepared and characterized by energy dispersive X-ray spectrometry, proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermal gravimetric analysis (TGA) and absorption and emission spectroscopies. The non-linear optical (NLO) profile of the prepared phthalocyanine (Pc) network polymer, derived from a nanosecond open-aperture Z-scan technique at 532 nm, shows a clear reverse saturable absorption and a high non-linear absorption coefficient ( α2) of 9.7 × 10−7 cm W−1. Optical limiting investigations indicated that the prepared Pc network polymer has a relatively low limiting threshold of 900 mJ cm−2. According to these results, the prepared Pc polymer is a promising material for many NLO applications.

Renewed interest in metal phthalocyanine donors for small molecule organic solar cells

Alternative metal phthalocyanine (m-Pc) donors employed in mixed layer organic solar cells (OSCs) are shown to have impressive photovoltaic parameters when compared to the traditional and well-studied copper phthalocyanine (CuPc) and zinc phthalocyanine (ZnPc) donors. In this work, we employ a mixed layer OSC with substantially different donor-to-acceptor mixing ratios to study a wide set of m-Pc donors. The different m-Pc donors are thus studied in consideration of their intrinsic physical properties, such as the valency of their central moiety and their molecular energy levels. The non-traditional m-Pc donors are better suited when employed in Schottky OSCs with high acceptor content, allowing for improvements to all major photovoltaic parameters. In contrast, traditional m-Pc donors suffer from unavoidable charge accumulation and recombination effects in the Schottky device architecture, and are instead optimized with the standard 1-to-1 donor-to-acceptor bulk heterojunction architecture. External quantum efficiency measurements show that optimization of short circuit current density requires balancing photocurrent contributions from the m-Pc absorption and the fullerene aggregate absorption, which is accomplished by control of the donor-to-acceptor mixing ratio. Chloroindium phthalocyanine (ClInPc):C60 OSCs are shown to be capable of near-IR absorption, promising power conversion efficiencies and open circuit voltages in excess of 1V.

Synthesis and photophysical properties of indium(III) phthalocyanine derivatives

Three chloroindium(III) phthalocyanine derivatives bearing four aromatic (naphthalene or pyrene) or aliphatic (hexylthio) groups were prepared from corresponding phthalonitrile compounds. The indium(III) phthalocyanine derivatives were characterized with elemental analyses, mass, proton nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FT-IR) and ultraviolet–visible spectroscopy (UV–vis) techniques. Quantum yields and the energy transfer from the substituents to phthalocyanine core were examined. No energy transfer was observed for 5. The energy transfer efficiency from pyrene units to indium phthalocyanine core was calculated as 0.27 for 6. Quantum yields of all samples were very small due to heavy atom effect of indium atom in the core. It was also observed that upon binding of pyrene and naphthalene units to indium phthalocyanine as substituents, the quantum yields of indium phthalocyanine parts of 5 and 6 decreased.

The effect of charge extraction layers on the photo-stability of vacuum-deposited versus solution-coated organic solar cells

Organic solar cells (OSCs) are studied for their photo-stability in inert atmosphere. Polymer solar cells with a bulk heterojunction (BHJ) of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) are contrasted with small molecule solar cells with a BHJ of chloroindium phthalocyanine (ClInPc) and C60-fullerene. A series of charge extraction layers at the hole and electron collecting contacts are examined for their role in OSC performance and stability. The inter-compatibilities of these extraction layers in vacuum-deposited small molecule OSCs (SM-OSCs) versus solution-coated polymer OSCs (P-OSCs) are explored. Through photo-stability studies, we show that interfacial extraction layers are necessary to avoid contact photo-degradation, which otherwise leads to strong reductions in OSC efficiencies. We also highlight certain extraction layer combinations that result in strong inter-electrode degradation, and we discuss incompatibilities in extraction layers among SM-OSCs versus P-OSCs. Our results suggest that the presence of excitons at the organic-electrode interface likely plays a critical role in contact photo-degradation. By minimizing contact photo-degradation, which dominates the majority of short-term OSC degradation, a new avenue for studying OSC stability behavior and opportunities to focus on other losses in OSCs become possible.

Optical characterization of electron beam evaporated chloroindium phthalocyanine thin films

In present study, the optical properties of chloroindium phthalocyanine (ClInPc) thin films prepared by electron beam evaporation have been investigated. The optical characteristics of the prepared thin films have been determined using spectrophotometric measurements of the absorbance, transmittance and reflectance at normal incidence in the spectral range 300–1,100 nm. Surface morphology of thin films is studied using field emission scanning electron microscopy. The absorption spectra recorded in UV-Visible region for the deposited films show two well defined intense absorption bands of phthalocyanine molecule; namely the Q-band and the Soret (B-band). The analysis of the spectral behavior of the absorption coefficient in the intrinsic absorption region have been performed to determine the optical band gap energy and type of the electronic transition, which reveals the probability of direct and indirect transitions. Moreover, by studying the absorption coefficient spectra just below the fundamental absorption edge, the width of band tails of localized states (Urbach energy), steepness parameter and width of the defect states have been evaluated. The obtained results of this novel grown ClInPc thin films support the desirable feature for the optoelectronic devices.

Low-LUMO 56π-electron fullerene acceptors bearing electron-withdrawing cyano groups for small-molecule organic solar cells

56π-Electron fullerene derivatives with electron-withdrawing cyano groups were synthesized by the reaction of 58π-electron fullerenes with NaCN, followed by in situ treatment with TsCN or MeOTf. The fullerene derivatives have low-lying LUMO levels, which are comparable with or lower than that of pristine C60. They were used as solution-processable electron acceptors in small-molecule organic solar cells that showed a maximum power conversion efficiency of 2.0% (JSC=7.05mA/cm2, VOC=0.62V and FF=0.45) using chloroindium phthalocyanine as an electron donor.

Influence of Electrode Surface Composition and Energetics on Small-Molecule Organic Solar Cell Performance: Polar versus Nonpolar Donors on Indium Tin Oxide Contacts

We present a systematic study of the band-edge energy offsets and shifts in local vacuum levels for indium tin oxide (ITO)/donor heterojunctions, using vacuum-deposited chloroindium phthalocyanine (ClInPc), titanyl phthalocyanine (TiOPc), pentacene (PEN), and copper phthalocyanine (CuPc) donor layers. We include a comparison of the performance of ITO/donor/C60 planar heterojunction (PHJ) organic solar cells (OPVs) as a function of activation and modification of the ITO contact. UV photoemission spectroscopy (UPS) was used to characterize the interfacial region between these donors and ITO to infer the ordering of these first deposited 1–2 monolayers as a function of ITO activation and modification. For the polar donors ClInPc and TiOPc, deposited on air plasma (AP) treated, high work function ITO (φeff ≈ 5.1–5.2 eV), shifts in local vacuum level observed during deposition of the first two monolayers of donor molecules suggest that the halo–metal or oxo–metal bond points (on average) toward the oxide surfa...

Doping Effect on Chloroindium Phthalocyanine (ClInPc)/C60 Solar Cells

ABSTRACTFor inorganic semiconductor solar cells, controlled doping is important because it can cause Fermi level shift of the inorganic semiconductor and achieve ohmic contact at the metal-semiconductor interface. In this paper we show that doping can also be used to shift Fermi level in organic semiconductors and cause changes in solar cell performance. We have made chloroindium phthalocyanine (ClInPc)/C60 heterojunction solar cells, where tetrafluoro-teracyano-quinodimethane (F4-TCNQ) is used to dope ClInPc layer. Ultraviolet photoemission spectroscopy (UPS) is used to investigate the ITO/ClInPc interfaces. The result shows that doping causes a Fermi level shift at the ITO/ClInPc interface as it does for inorganic semiconductors. As the doping increases, dark saturation current J0 of the solar cell increases, while open-circuit voltage Voc, short-circuit current Jsc and fill factor decreases. As a result, the efficiency of the solar cell decreases as doping increases. More UPS studies on ClInPc (doped with F4TCNQ)/C60 junction are needed to correlate the energy band diagram of the whole solar cell structure with the J-V characteristics.

Heteromorphic chloroindium phthalocyanine films for improved photovoltaic performance

A new structure incorporating multiple phases of chloroindium phthalocyanine (ClInPc) is fabricated and tested in photovoltaic devices. This so-called heteromorphic structure includes as-deposited and THF vapor treated ClInPc films to improve absorption and photovoltaic (PV) performance in devices. Absorption of the polymorphic phases of ClInPc are complementary and lead to improved current generation. Short circuit current is improved by over 70% using the heteromorphic structure, while power conversion efficiency (PCE) improves by more than 40% versus solely as-deposited devices. Advantages of the heteromorphic structure include broader spectral response, improved interfacial contact area and an intermediary open circuit voltage ( V oc).

Planar and textured heterojunction organic photovoltaics based on chloroindium phthalocyanine (ClInPc) versus titanyl phthalocyanine (TiOPc) donor layers

Planar and textured heterojunction solar cells (OPVs) are reported for vacuum deposited chloroindium phthalocyanine (ClInPc)/C 60 heterojunctions, and their response compared to previously explored OPVs based on titanyl phthalocyanine (TiOPc)/C 60 heterojunctions. As for TiOPc/C 60 OPVs, the photoelectrical activity of ClInPc/C 60 OPVs extends well into the near infrared, with good activity out to ca. 900 nm. As-deposited ClInPc films (Phase I) produce open-circuit photopotentials, V OC as high as ca. 0.8 V (Phase I form of ClInPc), ca. 0.15 V larger than previously observed for Phase I TiOPc/C 60 OPVs. The offsets in frontier orbital energies ( E HOMO Pc – E LUMO C 60 ) revealed by UV-photoemission studies (UPS) are slightly smaller for ClInPc/C 60 versus TiOPc/C 60 heterojunctions, and the interface dipole contribution (shift in local vacuum level) to these offsets is in the opposite direction for ClInPc/C 60 versus TiOPc/C 60 heterojunctions, or missing altogether, suggesting differences in molecular interaction at the Pc/C 60 interface. Higher V OC values are correlated with lower reverse saturation currents, J o , for ClInPc/C 60, versus other Pc or pentacene/C 60 heterojunctions, suggesting weak intermolecular interactions at the ClInPc/C 60 interface and large barriers to dark charge injection. Solvent annealing of the ClInPc films enhances the near-IR response, and textures the Pc film, enhancing the Pc/C 60 interfacial contact area and the short-circuit photocurrent, J SC . J SC under AM 1.5 illumination conditions was estimated by integration of the incident photon current efficiency (IPCE) response, to compare relative power conversion efficiencies for the two different device types. The estimated efficiency of Phase I ClInPc/C 60 OPVs is ca. 2.6%. The estimated AM 1.5 efficiency of ClInPc/C 60 OPVs with solvent annealed Pc layers is estimated to be ca. 3.3%, arising from the extensive texturing achieved of the Pc layer, which nearly doubles J SC for the Phase II versus Phase I Pc films.

Electrical parameters and gas sensing behaviour of ClInPc thin film devices

The electrical characteristics of thermally evaporated Chloroindium phthalocyanine thin films (ClInPc) are studied. A number of parameters are evaluated on the basis of the theory of space-charge-limited conduction. ClInPc thin films are extremely stable, in terms of both resistance to chemical attack and thermally, no hysteretic was observed after temperature cycling between room temperature and 500 K. DC current-voltage and current-temperature characteristics were obtained for ClInPc in vacuum and on exposure to dry air (20% O 2 ) in both the dark and under illumination with visible light. The conductivity data were analysed in the framework of band theory to elucidate information about the activation energy E ac , forbidden band gap (E c -E v ), domain or acceptor energy levels (E e , E h ). In the present work we also examine the response of ClInPc to O 2 and NO 2 at different temperatures.

Synthesis and 0.88 μm near-infrared electroluminescence properties of a soluble chloroindium phthalocyanine

A chloroindium phthalocyanine bearing phenoxyl substituents was synthesized and characterized by MS, 1H NMR and elemental analysis, which were consistent with the proposed structure; UV–vis absorption and photoluminescence (PL) spectra were also investigated. Near-infrared (NIR) organic light-emitting devices (OLEDs) were fabricated employing tris-(8-hydroxyquinoline) aluminum (Alq 3) and poly(vinylcarbazole) (PVK) which had been doped with chloroindium phthalocyanine. Room-temperature electroluminescence (EL) was observed near 0.88 μm due to transitions from the first excited singlet state to the ground state (S 1–S 0). As phthalocyanine possesses excellent solubility in common organic solvents, the light-emitting layer can be prepared by spin coating to simplify the fabrication process and so lower the manufacturing costs. The emission processes of this chloroindium phthalocyanine in the doped devices are discussed.

Optical‐Limiting and Photophysical Properties of Two Soluble Chloroindium Phthalocyanines with α‐ and β‐Alkoxyl Substituents

Two soluble heavy-metal phthalocyanine derivatives, namely, tetra-alpha-(2-ethylbutoxy) chloroindium phthalocyanine (alpha-InPcCl) and tetra-beta-(2-ethylbutoxy) chloroindium phthalocyanine (beta-InPcCl), were synthesized. Their optical-limiting properties in THF solution were investigated with a 532 nm nanosecond laser. The differences in the optical-limiting properties are attributed to their different photophysical properties. alpha-InPcCl is superior to beta-InPcCl as optical-limiting material, alpha substitution could be a useful factor to be considered in designing optical limiting materials based on metal phthalocyanines.

Preparation and characterization of chloroindium phthalocyanine nanoparticles from complexation-mediated solubilization

Chloroindium phthalocyanine (InClPc) nanoparticles embedded in poly(N-vinylcarbazole) (PVK) are obtained by the method of complexation-mediated solubilization, where InClPc is dissolved in high concentration in the aprotic organic solvent containing Lewis acid for the formation of electron donor-acceptor complexes. The fabricated InClPc nanoparticles are characterized by means of UV/VIS absorption, X-ray diffraction pattern, and TEM. The results show that the InClPc nanoparticles are spherical with a size of 25–50 nm. The broader diffraction peaks and the blue-shifted absorption for InClPc nanoparticles are observed. The photoconductivity of the InClPc nanoparticles in a single layered photoreceptor is investigated as well.