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Supramolecular assemblies of pyridyl porphyrin and diazadithia phthalocyanine
Journal of the Serbian Chemical Society , 1999,
Abstract: In this paper we report for the first time on a mixed complex between the cationic porphyrin 5, 10, 15, 20-tetra-N- -methyl-pyrydinium-p-il porphyrin (TMPyP) and a new metal phthalocyanine with four 16-membered diazadithia macrocycles (denoted here as Pc16), in order to obtain an active complex with an intense absorption on the lower energy side of the visible spectrum and with a higher sensitivity in photodynamic therapy of cancer. The dimerization constant for Pc16 and also the ratio between the oscillator strengths for monomeric and dimeric forms of this compound, were evaluated. The ratio between these oscillator strengths was 2.01 showing a certain dimerization process. The Job mathematical method allowed the establishment of the stoichiometry and the formation constants for the heteroaggregates between the porphyrin and the phthalocy- anine (a diad between one phthalocyanine molecule and one porphyrin molecule and a triad between two phthalocyanine molecules and only one porphyrin molecule). The coulombic attraction resulting from the p-p interaction of the two highly conjugated macrocycles and from the interaction between the substituents, favors a face-to-face geometry.
Piperidine-Substituted Perylene Sensitizer for Dye-Sensitized Solar Cells  [PDF]
Joe Otsuki,Yusho Takaguchi,Daichi Takahashi,Palanisamy Kalimuthu,Surya Prakash Singh,Ashraful Islam,Liyuan Han
Advances in OptoElectronics , 2011, DOI: 10.1155/2011/860486
Abstract: We have prepared a novel piperidine-donor-substituted perylene sensitizer, PK0002, and studied the photovoltaic performance in dye-sensitized solar cells (DSSCs). Physical properties and photovoltaic performance of this new perylene derivative PK0002 are reported and compared with those of unsubstituted perylene sensitizer, PK0003. PK0002, when anchored to nanocrystalline TiO2 films, achieves very efficient sensitization across the whole visible range extending up to 800?nm. The incident photon-to-current conversion efficiency (IPCE) spectrum was consistent with the absorption spectrum and resulted in a high short-circuit photocurrent density ( ) of 8.8?mA?cm?2. PK0002 showed higher IPCE values than PK0003 in the 520–800?nm region. Under standard AM 1.5 irradiation (100?mW?cm?2) and using an electrolyte consisting of 0.6?M dimethylpropyl-imidazolium iodide, 0.05?M?I2, 0.1?M?LiI, and 0.5?M tert-butylpyridine in acetonitrile, a solar cell containing sensitizer PK0002 yielded a short-circuit photocurrent density of 7.7?mA?cm?2, an open-circuit photovoltage of 0.57?V, and a fill factor of 0.70, corresponding to an overall conversion efficiency of 3.1%. 1. Introduction Dye-sensitized solar cells (DSSCs) have been widely investigated because of their simple structure and potential for low-cost production [1–3]. In this solar cell, a monolayer of dyes is attached to the surface of nanocrystalline TiO2 film to absorb solar light. The molecular design of dye-sensitizers that can absorb visible light of all colors for nanocrystalline oxide semiconductor solar cells is a challenging task as several requirements have to be fulfilled by the dye which are very difficult to be met simultaneously. Most of current research concerns development of panchromatic sensitizers based on organic dyes and transition metal complexes. Towards this goal, a number of transition metal complexes are used as effective sensitizers, due to their intense charge-transfer absorption over the whole visible range and highly efficient metal-to-ligand charge-transfer in a dye-sensitized solar cell device. DSSCs with dyes based on ruthenium complexes have achieved energy conversion efficiencies over 11% [4, 5]. In recent years, there has been much effort in replacing the ruthenium complexes with fully organic photosensitizers for environmental reasons, lower cost, and the possibility to obtain very high extinction coefficients, which could also allow application in thinner solar cells as demanded in, for example, solid-state DSSCs. Derivatives of perylene have been widely applied in various
Synthesis of Novel Porphyrin and its Complexes Covalently Linked to Multi-Walled Carbon Nanotubes and Study of their Spectroscopy  [cached]
Jin Jun,Dong Zhengping,He Jianguo,Li Rong
Nanoscale Research Letters , 2009,
Abstract: Novel covalent porphyrin and its complexes (Co2+, Zn2+) functionalized multi-walled carbon nanotubes (MWNTs) have been successfully synthesized by the reaction of the carboxyl on the surface of MWNTs which was synthesized to use carbon radicals generated by the thermal decomposition of azodiisobutyronitrile (AIBN) with 5-p-hydroxyphenyl-10,15,20-triphenyl-porphyrin and its complexes (Co2+, Zn2+). Three resulting nanohybrids were characterized by spectroscopy (FT-IR, Raman, and UV-vis), TGA, and TEM. The quality of porphyrin attached to the MWNTs was determined from thermogravimeric analysis (TGA) of the MWNTs, which showed a weight loss of about 60%. The Raman and absorption spectroscopy data showed that the electronic properties of modified MWNTs were mostly retained, without damaging their one-dimensional electronic properties. From fluorescence measurements, it was observed that the porphyrin and its complexes (Co2+, Zn2+) were nearly quenched by MWNTs, indicating that this covalently modified mode facilitated the effective energy or electron transfer between the excited porphyrin moiety and the extended π-system of MWNTs.
Study of Explosion Characteristics of Emulsion Explosive Sensitized by New Sensitizer

CHENG Yang-fan,MA Hong-hao,SHEN Zhao-wu,

实验力学 , 2012,
Abstract: Through underwater explosion experiment and explosion cutting experiment, energy output characteristic of emulsion explosive sensitized by new sensitizer was studied. Results show that compared with emulsion explosive sensitized by glass microspheres, the emulsion explosive sensitized by CMLS has a great improvement on explosive power. Dynamic sensitizing technology was adopted in CMLS type emulsion explosive preparation, so during detonation process, CMLS is decomposed and produces gas due to pressure, then small bubbles are distributed uniformly in the emulsion matrix, at last the emulsion matrix is sensitized. New sensitizer ensures charge with a high initial density, and can avoid half explosion and misfire due to the damaged of sensitization bubbles. The materials produced by CMLS decomposition are energetic groups which participate in detonation reaction, so the total energy output increases over 30%. It is expected that this new emulsion explosive will be further developed and applied extensively in practice.
Solid-Contact Perchlorate Sensor with Nanomolar Detection Limit Based on Cobalt Phthalocyanine Ionophores Covalently Attached to Polyacrylamide  [PDF]
Mohammad Nooredeen Abbas, Abdel Lattief A. Radwan, Philippe Bühlmann, Mahmud A. Abd El Ghaffar
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.27094
Abstract: Novel solid-contact perchlorate sensors based on cobalt phthalocyanine-C-monocarboxylic acid (I), and cobalt phthalocyanine-C,C,C,C-tetracarboxylic acid (II) as free ionophores and covalently attached to polyacryla- mide (PAA)—ionophores III and IV, respectively were prepared. The all solid-state sensors were constructed by the application of a thin film of a polymer cocktail containing a phthalocyanine ionophore and cetyltrimethylammonium bromide (CTMAB) as a lipophilic cationic additive onto a gold electrode precoated with the conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 10.3% of ionophore (III) covalently attached to plasticizer-free poly (butyl methacrylate-co-do- decyl methacrylate) (PBDA) exhibited a good selectivity for perchlorate and discriminated many ions, in- cluding F–, Cl–, Br–, I–, SCN–, , S2– and . The covalent attachment of the ionophore to the polymer resulted in a near-Nernstian anionic slope of –62.3 mV/decade whereas a super-Nernstian slope of –79.9 mV/ decade was obtained for the free ionophore. The sensor covered a linear concentration range of 5 × 10–9 - 1 × 10–2 mol?L–1 with a lower detection limit (LDL) of 1 × 10–9 mol?L–1 and gave a stable response over a pH range of 4 - 10.5. The all-solid state sensors were utilized for the selective flow injection potentiometric determination of perchlorate in natural water and human urine samples in the nanomolar concentration range.
Enhanced Nonlinear Absorption Performance of Reduced Graphene Oxide Nanohybrid Covalently Functionalized by Porphyrin via 1,3-Dipolar Cycloaddition  [PDF]
Nan Zhang, Xiaoqing Cong
Materials Sciences and Applications (MSA) , 2018, DOI: 10.4236/msa.2018.912070
Abstract: Porphyrin-functionalized reduced graphene oxide (RGO-TPP) was prepared by 1,3-dipolar cycloaddition reaction and characterized by Fourier transform infrared spectroscopy, Raman, ultraviolet/visible absorption, fluorescence, and transmission electron microscopy. At the same level of linear transmittance, RGO-TPP exhibited more enhanced optical nonlinearities than RGO and the pristineporphyrin, implying a remarkable accumulation effect as a result of the covalent link between RGO and porphyrin. The role of energy/electron transfer in the optical nonlinearities of RGO-TPP was investigated by fluorescence and Raman spectroscopy. All the results displayed that RGO can be covalently functionalized with porphyrins by the proposed approach.
Organic-Ruthenium(II) Polypyridyl Complex Based Sensitizer for Dye-Sensitized Solar Cell Applications  [PDF]
Lingamallu Giribabu,Varun Kumar Singh,Challuri Vijay Kumar,Yarasi Soujanya,Veerannagari Gopal Reddy,Paidi Yella Reddy
Advances in OptoElectronics , 2011, DOI: 10.1155/2011/294353
Abstract: A new high molar extinction coefficient organic-ruthenium(II) polypyridyl complex sensitizer (RD-Cou) that contains 2, ,6, -tetramethyl-9-thiophene-2-yl-2,3,5,6,6a,11c-hexahydro1H,4H-11oxa-3a-aza-benzoanthracene-10-one as extended -conjugation of ancillary bipyridine ligand, 4, -dicaboxy-2, , -bipyridine, and a thiocyanate ligand in its molecular structure has been synthesized and completely characterized by CHN, Mass, 1H-NMR, UV-Vis, and fluorescence spectroscopies as well as cyclic voltammetry. The new sensitizer was tested in dye-sensitized solar cells using a durable redox electrolyte and compared its performance to that of standard sensitizer Z-907. 1. Introduction The increasing demand for power supply as well as environmental concern for the consumption of fossil fuel have triggered a greater focus all over the world on renewable energy sources over the past decades [1]. In this context, solar energy appears to be very attractive alternate: covering 0.16% of the earth with 10% efficient solar conversion systems would provide power nearly twice the world’s consumption rate of fossil energy [2]. For this reason, dye-sensitized solar cells (DSSC) have emerged as one of the most promising candidates because of its cost-effective manufacturing, a respectable high efficiency and a remarkable stability under the prolonged thermal and light soaking dual stress among various photovoltaics [3–5]. A typical DSSC system consists of a nanocrystalline semiconductor that adsorbs a sensitizer on its surface, a Pt-counter electrode, and a redox mediator. The photosensitizer plays a crucial role in achieving higher photoconversion efficiency and has been actively studied globally. A wide variety of sensitizers have been studied for DSSC that includes various metal complexes, organic molecules, porphyrins, and phthalocyanines and so forth [6–9]. But only ruthenium-based sensitizers could have marked their way towards commercialization because of their high photoconversion efficiencies. The most successful ruthenium charge transfer sensitizers employed in such cells are bis(tetrabutylammonium)-cis-di(thiocyanato)-N,N′-bis(4-carboxylato-4′-carboxylic acid-2,2′-bipyridine)ruthenium(II) (the N719 dye) and trithiocyanato 4,4′4′′-tricaboxy-2,2′:6′,2′′-terpyridine ruthenium(II) (the black dye) produced solar-energy-to-electricity conversion efficiencies of >11% [10–13]. The high efficiency of these complexes are attributed to its suitable ground- and excited-state energy levels with respect to the nanocrystalline TiO2 conduction band energy and matching redox properties
Photophysical, Electrochemical and Photovoltaic Properties of Porphyrin-Based Dye Sensitized Solar Cell  [PDF]
William Ghann, Tulio Chavez-Gil, Carentxa I. Goede, Hyeonggon Kang, Shamsuddin Khan, Hany Sobhi, Fred Nesbitt, Jamal Uddin
Advances in Materials Physics and Chemistry (AMPC) , 2017, DOI: 10.4236/ampc.2017.75013
Abstract: Porphyrins occur in a number of important biomolecules and are also synthetically made for use as probe component of chemical and biological sensors. The performance of dye sensitized solar cells with two different porphyrin dyes was investigated in this work. The two porphyrin complexes comprised of a metal-free 5, 10, 15, 20-meso-tetrakis-(9H-2-fluorene-yl) porphyrin (H2TFP) and its Zinc complex (ZnTFP). UV-Vis, Fluorescence, and Fourier transformed infrared measurements of the two dyes were carried out to evaluate their absorption, emission and binding characteristics. Both dyes absorbed light in the UV-visible region all the way to the near-infrared. The surface morphology and elemental analysis of the porphyrin dye sensitized photoanodes were determined using Field Emission Scanning Electron Microscopy Imaging and Transmission Electron Microscopy Imaging. Cyclic voltammetry studies, current-voltage characteristics and the electrochemical impedance spectroscopic studies were also carried out. Solar-to-electric energy efficiency of H2TFP dye sensitized solar cell was higher (0.11%) than that of the zinc complex (0.08%). Thus the metal free porphyrin generated more power than the zinc complex under similar conditions. The impedance measurement also displayed less overall resistance for the free porphyrin (50 Ω) compared with the zinc complex (130 Ω). The LUMO levels of H2TFP and ZnTFP sensitizers were -0.87 eV and -0.77 eV respectively. Both of these LUMO values are higher than the lower bound level of the conduction band of TiO2 (-4.0 eV), ensuring the efficient injection of an electron from the excited porphyrin dye to the conduction band of the titanium dioxide.
Electrochemical determination of oncocalyxone A using an iron-phthalocyanine/iron-porphyrin modified glassy carbon electrode
Costa, Cicero de O.;Souza, Antonio A. de;Luz, Rita de Cássia S.;Lemos, Telma L. G.;Pessoa, Otília D. L.;Kubota, Lauro T.;Goulart, Marília O. F.;
Journal of the Brazilian Chemical Society , 2008, DOI: 10.1590/S0103-50532008000400013
Abstract: the development of a highly sensitive voltammetric sensor for oncocalyxone a using a glassy carbon electrode modified with a bilayer iron(ii) tetrasulfonated phthalocyanine (fetspc) and iron(iii) tetra-(n-methyl-4-pyridyl)-porphyrin (fet4mpyp) is described. the modified electrode showed high catalytic activity and stability for the oncocalyxone a reduction, provoking the anodic shift of the reduction peak potentials of ca. 30 mv and presenting much higher peak currents than those obtained on the bare gc electrode. a wide linear response range between 0.005-1.2 μmol l-1, with a sensitivity of 8.11 μa l μmol-1 and limits of detection (lod) and quantification (loq) of 1.5 and 5 nmol l-1 were obtained with this sensor.
A comparison of iron phthalocyanine and cobalt porphyrin on the electrochemical catalysis in Ni-MH battery
Fang Wang,Feng Wu,Shi Chen,XinPing Qiu,LiQuan Chen
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-2217-2
Abstract: The effects of iron phthalocyanine (FePc) and cobalt porphyrin (CoPp) on inner pressure and cycle behavior of sealed Ni-MH batteries were investigated in this study. The morphology of battery electrode was observed by SEM. The electrochemical impedance spectroscopy of floating-charge/discharge battery was also measured. Experimental results show that the addition of FePc or CoPp to the alloy electrode is an effective approach to decrease the internal pressure of battery during the process of charge and overcharge. In contrast to CoPp, the battery with FePc exhibits a slower capacity decay and a smaller overpotential at the same charge-discharge rate. As an electrocatalyst, FePc may more effectively speed up the reduction of oxygen, and decrease its reduction potential. As a result, the charge process is accelerated, the gas evolution is reduced and the pulverization of electrode materials is slowed down.
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