Polymeric Phthalocyanine Research Articles

One-pot synthesis of copper phthalocyanine polymer: An efficient CO2 fixation catalyst

The chemical transformation of CO2 into high-value-added products is not only favourable to environmental preservation, but also promising for economy. Developing novel and practical catalysts play a critical role in facilitating conversion of CO2 and the synthesis of high value-added chemicals. Herein, we present the fabrication of biphenyl-typed copper phthalocyanine polymer (BPh-CuPc) from 4,4’-bis(3,4-dicyanophenoxy)biphenyl via a one-pot synthesis procedure, and application of it as a promising catalyst for CO2 conversion into cyclocarbonate. FTIR, XPS, UV–vis, TGA and SEM measurements confirm the successful fabrication of BPh-CuPc. Attributing to the existence of copper ions which can act as a Lewis acid to activate epoxide, and phthalocyanine rings that is positive for CO2 absorption, within the chemical framework of BPh-CuPc, it exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions when combined with tetrabutylammonium iodide (TBAI). As a result, a 98 % yield and 99 % selectivity are obtained for the BPh-CuPc/TBAI system in CO2/propylene oxide conversion under condition of 90 °C, 8 h and 2.0 MPa. The obtained high yield and selectivity, as well as remarkable stability and versatility, validate the promising application of BPh-CuPc as a CO2 conversion catalyst. SynopsisAttributing to the existence of copper ions and phthalocyanine rings within the chemical framework, BPh-CuPc exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions.

Fabrication of Phthalocyanine Polymers with Abundant Nitrogen Active Sites as the Cathode Materials for Aqueous Zinc-Organic Batteries

Fabrication of Phthalocyanine Polymers with Abundant Nitrogen Active Sites as the Cathode Materials for Aqueous Zinc-Organic Batteries

The Flower-Shaped Co (II) and Cu (II) Phthalocyanine Polymers as Highly Efficient and Stable Catalysts for Chemical Fixation of CO2 to Cyclic Carbonate

New flower-shaped metallophthalocyanine polymers (THB-4-M, M = Co, Cu) have been synthesized by using 1,3,5-Tri(4-hydroxyphenhyl) benzene (THB) as rigid and contorted units to control the morphology under the solvothermal method. The polymers were characterized using FT-IR, UV-vis, SEM, TGA, and XPS. These polymers were applied as heterogeneous catalysts for the chemical fixation of carbon dioxide (CO2) to cyclic carbonates without solvent. The influence of reaction parameters and different metal centers on the catalytic performance were studied in detail. Under optimal conditions, the catalysts showed high conversion (49.9–99.0%), selectivity (over 85%), and reusability at ambient conditions (at 1 bar CO2).

The effective polymeric macromolecule as peroxymonosulfate activator as an alternative to metal oxides in the treatment of organic dye pollutants

Catalyst efficiency is affected by inhomogeneous catalyst atom placement on the substrate, leading to nano-level aggregation and reduced performance. Research on single-atom catalysts aims to place them at the atomic level to maximize efficiency, but faces challenges and high costs. This study presents a cost-effective approach using polymeric phthalocyanine Co(II) complex (poly-CoPc) prepared by a simple method. Poly-CoPc shows superior catalytic activity by acting as a catalyst without requiring additional processing. Co(II) atoms in the polymer matrix are covalently coordinated into single atoms and inhibit nanoparticle growth. The poly-CoPc/PMS system outperforms Co3O4 and unsubstituted cobalt phthalocyanine, achieving 97.06% Rhodamine B degradation in 20 min. Furthermore, the poly-CoPc proves to be the most effective, with a degradation efficiency of 69.94% for tap water and 95.76% for seawater, producing predominantly 1O2. These results position poly-CoPc as a promising PMS activator for environmental treatment that surpasses metal oxide derivatives in terms of activity and properties.

Computation of reverse neighbourhood degree-based topological indices for the transition metal phthalocyanine polymers (poly-TMPc)

In this article, we discuss the reverse neighbourhood degree-based topological indices for the transition metal phthalocyanine polymers (poly- TMPc). Degree-based topological indices have been extensively studied and linked to a variety of chemical properties. An even more recently established methodology for assessing chemical systems and geometries is the use of numerical descriptors based on the degree of definition defined by the reverse-degree concept technique. It highlights molecular characteristics as numerical descriptors based on the reverse-degree concept’s degree of definition and delivers numerical descriptors in algebraic form. On the other hand, due to their high catalytic activity, photostability, resistance to severe environments, and adaptable properties, transition metal phthalocyanines are a fascinating class of organic semiconductors. Furthermore, different types of reverse neighbourhood topological indices, such as the augmented Zagreb index, first and second Zagreb indexes, and Randi ć indexes, are defined and used to assess the complexity, stability, and other properties of poly-TMPc(m,n).

Organic hybrid of cobalt phthalocyanine embedded graphene as an efficient catalyst for oxygen reduction reaction

The widespread practical applications of the fuel cells are dependent on the rational development of state-of-the-art easily synthesizable or earth-abundant catalysts for oxygen reduction reaction (ORR). This work demonstrates the utilization of cobalt phthalocyanine polymer (pCoPc) encased graphene (Gr) layer with an extensive π-π interaction as a proficient and non-precious electrocatalyst for ORR. The synthesized material is characterized by UV–vis, IR, Mass, NMR, SEM, TEM and XPS techniques. The fabricated Gr-pCoPc catalyst exhibited significant enhancement in the ORR performance which is comparable to the benchmark Pt/C catalyst with a decent durability in alkaline media. More importantly, the ORR onset potential at Gr-pCoPc shifted towards the positive potential by 10 mV compared to the Pt/C catalyst. The enhancement observed in the ORR performance and stability of the Gr-pCoPc catalyst could be attributed to the combined impact created by the outstanding electronic and conductive attributes of graphene, along with the π-stacking interactions inherent in pCoPc. In comparison to prior catalysts in literature and Pt/C, Gr-pCoPc displayed a notably lower Tafel slope of 64 mV dec-1 and larger double layer capacitance, Cdl value of 9.5 mF cm−2. The RDE experiments indicated that the hybrid composite of Gr-pCoPc facilitated an effective 4-electron pathway during ORR. Gr-pCoPc catalyst is highly durable towards ORR and it retained > 92.5 % of its initial ORR activity even after 5000 repeated cycles.

Electronic structure, optical properties and high thermoelectric figure of merit in iron phthalocyanine polymer: FP-LAPW comparative studies

The comparative study of optoelectronic and thermoelectric properties of Iron phthalocyanine polymer, FePc, has been performed using the full-potential linearized augmented plane wave (FP-LAPW) method. The results show that the band gap of FePc is 2.039 eV with two deep trap bands. Optical spectra such as the real and imaginary parts of the dielectric function, reflectivity, electron energy loss spectroscopy, refractive index, extinction, and absorption coefficients are calculated and the main peaks are compared with the available experimental data. Calculated optical spectra are in good agreement with the experimental data of diethylamine and triethylamine polymers. The maximum values of 2190.2 μVK−1 and 1.02 are obtained for the Seebeck coefficient and the figure of merit ZT at 300 K for the chemical potentials near the Fermi level, respectively. The results show that FePc polymer is a good candidate for optoelectronic device applications.

Hybrid cobalt phthalocyanine polymer as a potential electrocatalyst for hydrogen evolution reaction

In this work, simple, novel, eco-friendly, low-cost and highly-active cobalt oxytyramine phthalocyanine polymer, poly[CoOTPc] is synthesized and characterized with various spectro-analytical techniques to demonstrate the successful construction of poly[CoOTPc]. In order to enhance the conductivity and electrocatalytic performance of poly[CoOTPc], an organic-hybrid composite with Ketjen-Black (KB) is prepared in different ratios and their activity was assessed towards hydrogen evolution reaction (HER). The linear sweep voltammogram of organic-hybrid composite (3.5:1.5 ratio of polymer to KB) exhibited least overpotential of −79 mV at −10 mA cm−2 current density towards HER in 0.5 M H2SO4 with a Tafel slope closer to the standard catalyst (Pt/C) both in lower and higher overpotentials. In addition, lower charge-transfer resistance is noticed at the hybrid catalyst and is comparable with the standard catalyst suggesting that the designed poly[CoOTPc]+KB organic-hybrid composite is one of the superior, low-cost electrocatalyst towards HER with excellent stability and efficiency for the large-scale integrated green energy systems.

Polymeric cobalt phthalocyanine on nickel foam as an efficient electrocatalyst for oxygen evolution reaction

Renewable energy is of prime importance for sustainable development. Hydrogen is considered as clean as well as an efficient energy source. In addition to H2 as fuel, polymer electrolyte membrane fuel cell requires oxygen as an oxidant. Electrocatalytic or photocatalytic water splitting processes yield H2 and O2. Compared to hydrogen evolution reaction (HER), the oxygen evolution reaction (OER) in water electrolysis is a very sluggish and slow process. Even precious and costly catalysts have demonstrated higher overpotential for OER. To overcome the issues related to overpotential as well as cost and durability, bio-inspired macrocycles and polymers based on phthalocyanine are being explored extensively because of their unique and versatile properties. In this effort, a novel cobalt phthalocyanine polymer (poly-CoTPzPyCPc) was synthesised and employed as a low-cost and efficient organic-based catalyst for OER. The characterized polymeric catalyst was coated on Ni foam and the fabricated electrodes were evaluated for OER in 0.1 M KOH. The electrodes Ni-foam, Ni/poly-CoTPzPyCPc, Ni/IrO2, and Ni/poly-CoTPzPyCPc + IrO2 exhibited an onset potential for OER at 1.57, 1.53, 1.47 and 1.43 V Vs. RHE, respectively. The Ni/poly-CoTPzPyCPc exhibited an overpotential of 365 mV (±2 mV) at a current density of 10 mA cm−2. Furthermore, the composite of poly-CoTPzPyCPc with IrO2, displayed surprisingly superior OER activity. The composite achieved a current density of 10 mA cm−2 at lower overpotential of 274 mV (±2 mV) than the polymeric phthalocyanine and benchmark IrO2 catalyst which showed an overpotential of 324 mV at the same current density. The Tafel slope value was found to be 89, 67, 34 and 31 mV/dec for pure Ni foam, Ni/poly-CoTPzPyCPc, Ni/IrO2 and Ni/poly-CoTPzPyCPc + IrO2, respectively. The stability studies performed on poly-CoTPzPyCPc + IrO2 composite catalyst revealed that the proposed catalyst is stable and can be successfully employed for OER in water electrolysis. The developed composite catalyst has a small amount loading of precious catalyst with simple organic based catalyst to achieve efficiency better than benchmark catalyst for OER.

Polymeric Phthalocyanine-Based Nanosensitizers for Enhanced Photodynamic and Sonodynamic Therapies.

Photodynamic therapy and sonodynamic therapy are two highly promising modalities for cancer treatment. The latter holds an additional advantage in deep-tumor therapy owing to the deep penetration of the ultrasonic radiation. The therapeutic efficacy depends highly on the photo/ultrasound-responsive properties of the sensitizers as well as their tumor-localization property and pharmacokinetics. A novel nanosensitizer system based on a polymeric phthalocyanine (pPC-TK) is reported herein in which the phthalocyanine units are connected with cleavable thioketal linkers. Such polymer could self-assemble in water forming nanoparticles with a hydrodynamic diameter of 48nm. The degradable and flexible thioketal linkers could effectively inhibit the π-π stacking of the phthalocyanine units, rendering the resulting nanoparticles an efficient generator of reactive oxygen species upon light or ultrasonic irradiation. The nanosensitizer could be internalized into cancer cells readily, inducing cell death by efficient photodynamic and sonodynamic effects. The potency is significantly higher than that of the monomeric phthalocyanine (PC-4COOH). The nanosensitizer could also effectively inhibit the growth of tumor in liver tumor-bearing mice by these two therapies without causing noticeable side effects. More importantly, it could also retard the growth of a deep-located orthotopic liver tumor in vivo by sonodynamic therapy.

Sodium‐Coordinated Polymeric Phthalocyanines as Stable High‐Capacity Organic Anodes for Sodium‐Ion Batteries

Sodium‐ion batteries (SIBs) have attracted considerable interest as an alternative to lithium‐ion batteries owing to their similar electrochemical performance and superior long‐term cycle stability. Organic materials are regarded as promising anode materials for constructing SIBs with high capacity and good retention. However, utilization of organic materials is rather limited by their low energy density and poor stability at high current densities. To overcome these limitations, we utilized a novel polymeric disodium phthalocyanines (pNaPc) as SIB anodes to provide stable coordination sites for Na ions as well as to enhance the stability at high current density. By varying the linker type during a one‐pot cyclization and polymerization process, two pNaPc anodes with O‐ (O‐pNaPc) and S‐linkers (S‐pNaPc) were prepared, and their structural and electrochemical properties were investigated. The O‐pNaPc binds Na ions with a lower binding energy compared with S‐pNaPc, which leads to more facile Na‐ion coordination/dissociation when engaged as SIB anode. The use of O‐pNaPc significantly improves the redox kinetics and cycle stability and allows the fabrication of a full cell against Na3V2(PO4)2F3/C cathode, which demonstrates its practical application with high energy density (288 Wh kg−1) and high power density (149 W kg−1).

Molecular Modulation of Sequestered Copper Sites for Efficient Electroreduction of Carbon Dioxide to Methane

AbstractThe sustainable production of methane (CH4) via the electrochemical conversion of carbon dioxide (CO2) is an appealing approach to simultaneously mitigating carbon emissions and achieving energy storage in chemical bonds. Copper (Cu) is a unique material to produce hydrocarbons and oxygenates. However, selective methane generation on Cu remains a great challenge due to the preferential *CO dimerization pathway toward multi‐carbon (C2+) products at neighboring catalytic sites. Herein, a conjugated copper phthalocyanine polymer (CuPPc) is designed by a facile solid‐state method for highly selective CO2‐to‐CH4 conversion. The spatially isolated CuN4 sites in CuPPc favor the *CO protonation to generate the key *CHO intermediate, thus significantly promoting the formation of CH4. As a result, the CuPPc catalyst exhibits a high CH4 Faradaic efficiency of 55% and a partial current density of 18 mA cm−2 at −1.25 V versus the reversible hydrogen electrode. It also stably operates for 12 h. This study may offer a new solution to regulating the chemical environment of the active sites for the development of highly efficient copper‐based catalysts for electrochemical CO2 reduction.

Simultaneous Detection of Dopamine and Paracetamol on Electroreduced Graphene Oxide–Cobalt Phthalocyanine Polymer Nanocomposite Electrode

Simultaneous Detection of Dopamine and Paracetamol on Electroreduced Graphene Oxide–Cobalt Phthalocyanine Polymer Nanocomposite Electrode

Thermal Properties and Flammability Characteristics of a Series of DGEBA-Based Thermosets Loaded with a Novel Bisphenol Containing DOPO and Phenylphosphonate Units.

Despite a recent sustained preoccupation for developing biobased epoxies with enhanced applicability, such products have not been widely accepted for industry because of their inferior characteristics compared to classic petroleum-based epoxy thermosets. Therefore, significant effort is being made to improve the flame retardance of the most commonly used epoxies, such as diglycidyl ether-based bisphenol A (DGEBA), bisphenol F (DGEBF), novalac epoxy, and others, while continuously avoiding the use of hazardous halogen-containing flame retardants. Herein, a phosphorus-containing bisphenol, bis(4-(((4-hydroxyphenyl)amino)(6-oxido-6H-dibenzo[c,e][1,2]oxaphosphinin-6-yl)methyl)phenyl) phenylphosphonate (BPH), was synthesized by reacting bis(4-formylphenyl)phenylphosphonate with 4-hydroxybenzaldehyde followed by the addition of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) to the resulting azomethine groups. Environmentally friendly epoxy-based polymer thermosets were prepared by using epoxy resin as polymer matrix and a mixture of BPH and 4,4'-diaminodiphenylsulfone (DDS) as hardeners. A hyperbranched phthalocyanine polymer (HPc) and BaTiO3 nanoparticles were incorporated into epoxy resin to improve the characteristics of the final products. The structure and morphology of epoxy thermosets were evaluated by infrared spectroscopy and scanning electron microscopy (SEM), while the flammability characteristics were evaluated by microscale combustion calorimetry. Thermal properties were determined by thermogravimetric analysis and differential scanning calorimetry. The surface morphology of the char residues obtained by pyrolysis was studied by SEM analysis.

Boosting Electrocatalytic CO 2 Reduction with Conjugated Bimetallic Co/Zn Polyphthalocyanine Frameworks

Boosting Electrocatalytic CO ₂ Reduction with Conjugated Bimetallic Co/Zn Polyphthalocyanine Frameworks

Synthesis and Sensor Properties of Silicon Phthalocyanine Axially Substituted with Bis-(Prop-2-Ynyloxy) Groups and Polymeric Phthalocyanines Bearing PEG Substituent by “Click” Chemistry

Synthesis and characterization of new axially substituted phthalocyanine complexes were done. Bis - (prop-2-ynyloxy) phthalocyaninato silicon (IV) compound was obtained from the reaction of 2-propin-1-ol with SiPcCl2. Polymeric phthalocyanine containing axially substituted PEG was obtained from the reaction of bis - (prop-2-ynyloxy) phthalocyaninato silicon (IV) compound and polyethylene glycol azido. The structure of the compounds was justified by FT-IR, 1H NMR, 13C NMR, UV–Vis, and mass spectra. The photophysical and photochemical properties of the phthalocyanine compound axially substituted with bis-(prop-2-ynyloxy) was investigated. Properties of the compounds were examined in terms of fluorescence quantum efficiency and singlet oxygen generating capacity, and the potential photosensitizer capacity of the compound was determined. In addition, polyethylene glycol group was added to the phthalocyanine compound by click reaction. The polymer product was obtained in blue color. Phthalocyanine(Pc) containing PEG polymeric units is soluble in dimethyl sulfoxide (DMSO). Absorption measurements of the compound at different concentrations were made. Both polyethylene glycol (PEG) and phthalocyanine compounds can be used in the manufacture of medical supplies due to their non-toxicity. UV–visible study of Bis-(prop-2-ynyloxy) phthalocyaninato silicon (IV) compound revealed its high selectivity for Fe3+ ion recognition.

Tetraphenolphthalein Cobalt(II) Phthalocyanine Polymer Modified with Multiwalled Carbon Nanotubes as an Efficient Catalyst for the Oxygen Reduction Reaction.

Oxygen reduction reaction (ORR) is the main reaction at the cathode of a fuel cell that utilizes Pt/C as the benchmark catalyst. Due to sluggish activity, high cost, rare abundance, and durability issues, Pt/C must be replaced by nonprecious, stable, and easily synthesizable materials. This work involves the synthesis of novel, simple, low-cost, and environmentally friendly phenolphthalein-bearing cobalt(II) phthalocyanine polymer, poly(CoIITPpPc) dyad, as an efficient catalyst for ORR. The results of analytical characterizations reveal the formation of the poly(CoIITPpPc) polymer in the pure state. To further enhance the catalytic response of poly(CoIITPpPc), a hybrid composite is prepared using poly(CoIITPpPc) and multiwalled carbon nanotubes (MWCNTs) that increase the surface area and conductivity. The poly(CoIITPpPc) and hybrid composite are separately deposited on the electrode surfaces. The electron microscopy images confirm the uniform distribution of the poly(CoIITPpPc) molecules on the electrode surface and MWCNTs. The poly(CoIITPpPc) and hybrid composite electrodes are evaluated for ORR, and the hybrid composite exhibits better onset potential at 0.803 V versus reversible hydrogen reference electrode for ORR according to linear sweep voltammograms (LSVs). The obtained data are superior compared to those of other carbon-based redox-active materials reported previously and nearer to those of the benchmark catalyst (Pt/C). The rotating disc electrode measurement of the hybrid composite electrode confirms the total number of electrons involved in ORR to be four. Furthermore, the hybrid composite electrode exhibits an excellent stability for 100 LSV scans. The synergistic effect of poly(CoIITPpPc) and MWCNTs leads to the surprisingly high ORR activity due to the improved surface area, conductivity, and interfacial confined surface.

Photoelectrochemical sensor based on zinc phthalocyanine semiconducting polymer dots for ultrasensitive detection of dopamine

Developing materials with excellent photoelectric activity is critical to improving the sensitivity of photoelectrochemical (PEC) sensors. Herein, we reported a convenience method to synthesize phthalocyanine polymer dots (Pdots), which dope zinc phthalocyanine (ZnPc) into a conjugated polymer poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo{2,1,3}thiadia-zol-4,8-diyl)] (P8BT). The synthesized materials were characterized by energy dispersive spectrometry (EDS), electrochemical impedance spectroscopy (EIS), fluorescence (FL) spectroscopy, transmission electron microscopy (TEM), ultraviolet-visible diffuse reflectance spectroscopy (UV–vis DRS), and dynamic light scattering (DLS). Then, ZnPc-P8BT-Pdots were modified on an indium tin oxide (ITO) electrode by repeated immersion to develop an ultrasensitive PEC sensor for dopamine (DA) detection. Semiconducting polymers in ZnPc-doped forms exhibit a typical photocurrent reduction in comparison with the original polymers. As the photocurrent was weakened, energy was transferred from the conjugated polymers to ZnPc. The photocurrent intensity of ZnPc-P8BT-Pdots/ITO increases as the concentration of DA increases under blue light irradiation. Under the best experimental conditions, the PEC sensor realized the detection of DA (2.5 nM-125 μM) with a limit of detection (LOD) of 1.69 nM (S/N = 3). Moreover, the ZnPc-P8BT-Pdots/ITO sensor for the detection of DA exhibited superior PEC performance, high sensitivity, rapid response, and favorable stability. This study indicated that ZnPc-P8BT-Pdots possess the promising potential to construct PEC sensors for pharmaceutical analysis.

Precise construction of lithiophilic sites by diyne-linked phthalocyanine polymer for suppressing metallic lithium dendrite.

Uncontrolled growth of lithium dendrite is the key challenge that impedes the practical application of Li anodes in high-energy-density Li-metal batteries. Precisely constructing lithiophilic active sites on the anode surface is expected to be an effective strategy for promoting the anode interfacial properties and alleviating the dendrite growth of lithium. Herein, a diyne-linked phthalocyanine polymer (PcEP) with precise lithiophilic active sites is designed and constructed in a bottom-up manner in situ on the surface of the copper foil via the coupling reaction of tetraethynylphthalocyanine. The lithiophilic electron-rich pyrrolic nitrogen and aza nitrogen in the Pc structure, and the sp-hybridized carbon in the diyne linkage (-CC-CC-) in PcEP can conduct the homogeneous nucleation and deposition processes of lithium, and thus suppress the dendrite growth. This dendrite-free metallic lithium anode exhibits reduced overpotential, high coulombic efficiency (98.6%), and prolonged lifespan (200% longer than that of a Cu anode). These impressive achievements demonstrate that the advanced phthalocyanine polymer might be a promising material for addressing the critical interfacial issues related to the next-generation high-energy-density Li-metal-based storage devices.

Phthalocyanine polymer grafted graphene oxide matrix as high-performance anode material for lithium-ion batteries

GO-CONH-NiPc is synthesized by grafting CONH-NiPc onto a GO matrix, which displays a larger specific surface area, exposes more active sites and accelerates the migration rate of Li+. As a result, better electrochemical behaviors are observed.