bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling of Proton Conductivity through Perfluorosulfonate Acid Electrolyte Membranes
Authors: Zhang Bo , Edwards Brian Joseph 
Published: February 2020

Proton conductivity (σ) through perfluorosulfonate acid (PFSA) polymer electrolyte membranes was modelled from the unsaturated hydraulic conductivity, which was described as a power-law function of water content; i.e.,λ
q
, where λ is the water content and the exponent q is a porosity factor. In this study, the membrane was modeled as a network of nanopores with the anionic groups (i.e., –SO3
–) assumed to be fixed along the pore wall according to an indeterminate distribution consistent with the material’s equivalent weight (EW) and dry membrane density. The transport of the hydronium ions inside the porous network was expressed using the extended Nernst-Einstein equation, which was modified using continuum percolation theory to reveal the relevant transport mechanisms at different water contents and temperatures. The power q in the modification was compatible with the critical path analysis simulation results; i.e., q=1.28±0.07 in two dimensions and q=1.86±0.19 in three dimensions, depending singularly on the dimensionality of the transport system. The average electrical conductivity of the membrane was deduced in terms of the following quantities: water content, equivalent weight, and the nature of the perfluorosulfonate acid polymer side chain. Theoretical predictions of this model were compared against experimental data of conductivity for four different membranes: DuPont’s Nafion 117 (EW = 1100), Membrane C (EW = 900) of Chlorine Engineers Corp., Japan, Dow Chemical’s XUS 13204.10 (EW = 800), and a 3M membrane developed by 3M Corp. (EW = 1000) for different water contents and temperatures. The theoretical predictions of the model matched the experimental data with reasonable quantitative accuracy in most cases.
Ring-Expanded Phthalocyanines Fused with Fluorene Skeleton for Light-Harvesting in the Near-IR Region
Authors: Yamamoto Satoshi , Kimura Mutsumi 
Published: February 2020

Organic photovoltaic devices (OPVs) based on thin films of organic semiconductors have been intensely investigated as a promising candidate for low-cost, lightweight, and scalable solar cells. While OPVs have achieved high conversion efficiencies, their organic semiconductors mainly absorb the light in visible range. To enhance their efficiency, the expansion of light-harvesting range is a key issue in this field.
Phthalocyanines (Pcs) and their metal complexes (MPcs), synthetic porphyrin analogues, have been widely investigated as near-IR absorbing dyes because of their intense Q band (600-700 nm), high molar extinction coefficients (e > 100000 M-1 cm-1), and excellent thermal, chemical, and photolytic stabilities. The electronic structure and properties of MPcs can be tailored by modifying the macrocyclic ligands and changing the central metals [1].
We present here designed and synthesized novel ring-expanded zinc phthalocyanine (ZnFc , Figure1), in which four fluorene rings were fused with porphyrazine ring. Fusing fluorene rings with the porphyrazine rings lead to red-shifting the Q band and tailoring of the HOMO and LUMO energy levels as well as an expansion of p-system. We demonstrated the expansion of the light-harvesting area in BHJ solar cells based on poly(3-hexylthiophen) (P3HT) and 1-(3-methoxycalbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) by co-sensitizing with ZnFc. When the ZnFc decorated with eight alkyl chains was added to P3HT/PCBM BHJ solar cells, the solar cells showed a higher device efficiency with 16 % enhancement of JSC
as compared with that of the reference P3HT/PCBM BHJ solar cells due to the expansion of light-harvesting range [2].
We also synthesized an asymmetrical fluorene-fused phthalocyanine (FcS1, Figure1), which containing three fused fluorene rings and one carboxylic acid. FcS1 indicated a potential for near-IR sensitizer in DSSCs. The absorption spectrum of FcS1 adsorbed onto a nano-crystalline TiO2 film suggested the formation of J-aggregation with tilted orientation of macrocyclic ligands. While the DSSC cells sensitized by FcS1 showed a modest efficiency of 3.2 % under simulated air mass 1.5 global sunlight, FcS1 could convert the red and near-IR light regions between 600 and 860 nm [3].

Reference

[1] J. Mack, N. Kobayashi, Chem. Rev.
2011, 111, 281-321.
[2] S. Yamamoto, M. Kimura, ACS Appl. Mater. Interfaces
2013, 5, 4367-4373.
[3] S. Yamamoto, T. Ikeuchi, S. Mori, M. Kimura, Asian J. Org. Chem.
2014, 10, 1083-1088.

Figure 1
Porphyrins As Excellent Sensitizers for Dye-Sensitized Solar Cells
Authors: Imahori Hiroshi 
Published: February 2020

Recently we have developed aromatic ring-fused, unsymmetrically pi-elongated porphyrins (i.e., naphthalene-fused and quinoxaline-fused porphyrins) that showed broadened, and red-shifted light absorption properties compared to the corresponding porphyrin references, resulting in the power conversion efficiencies of 4.1% and 6.3%, respectively. As demonstrated for other sensitizers in DSSCs, introduction of both electron-donating and electron-withdrawing substituents to a core of pi system would be appealing for the modulation of the light-harvesting properties of sensitizers. In this talk I will present our recent advance in porphyrin-sensitized solar cells.1-10 In particular, I will focus on novel push-pull porphyrins for porphyrin-sensitized solar cells.1-10 For instance, we synthesized for the first time a push-pull porphyrin dye bearing two diarylamino groups and two carboxyphenylethynyl groups as electron-donating and electron-withdrawing anchoring groups, respectively. The absorption spectrum displayed broad and red-shifted absorption, achieving panchromic light-harvesting in visible and NIR regions. Introduction of multiple push-pull groups into meso-positions is a promising strategy for the rational design of porphyrin sensitizers for light-harvesting applications. The preliminary photovoltaic performance is moderate (3.0%), but the extensive photocurrent generation matches with the excellent light-harvesting ability. Further modulation of the photovoltaic properties of porphyrin DSSCs will be possible by suitable selection of electron-donating and electron-withdrawing groups as well as introduction of the substituents into the porphyrin core.
[1] H. Imahori, T. Umeyama, and S. Ito, Acc. Chem. Res.
42, 1809 (2009).
[2] H. Imahori, S. Kang, H. Hayashi, M. Haruta, H. Kurata, S. Isoda, S. E. Canton, Y. Infahsaeng, A. Kathiravan, T. Pascher, P. Chabera, A. P. Yartsev, and V. Sundström, J. Phys. Chem. A, 115, 3679 (2011).
[3] H. Imahori, H. Iijima, H. Hayashi, Y. Toude, T. Umeyama, Y. Matano, and S. Ito, ChemSusChem, 4, 797 (2011).
[4] M. Simon, H. Iijima, Y. Toude, T. Umeyama, Y. Matano, S. Ito, N. V. Tkachenko, H. Lemmetyinen, and H. Imahori, J. Phys. Chem. C, 115, 14415 (2011).
[5] H. Imahori, T. Umeyama, K. Kurotobi, and Y. Takano, Chem. Commun. (Feature Article), 48, 4032 (2012).
[6] H. Hayashi, A. S. Touchy, Y. Kinjo, Y. Toude, K. Kurotobi, T. Umeyama, Y. Matano, and H. Imahori, ChemSusChem, 6, 508 (2013).
[7] S. Ye, A. Kathiravan, H. Hayashi, Y. Tong, Y. Infahsaeng, P. Chabera, T. Pascher, A. P. Yartsev, S. Isoda, H. Imahori, and V. Sundström, J. Phys. Chem. C, 117, 6066 (2013).
[8] K. Kurotobi, K. Kawamoto, Y. Toude, Y. Fujimori, Y. Kinjo, S. Ito, Y. Matano, and H. Imahori, Chem. Lett., 42, 725 (2013).
[9] K. Kurotobi, Y. Toude, K. Kawamoto, Y. Fujimori, S. Ito, P. Chabera, V. Sundström, and H. Imahori, Chem. Eur. J., 19, 17075 (2013).
[10] T. Higashino and H. Imahori, Dalton Trans. (Perspective), in press.
Chemistry of Novel Non-Aromatic, Meso-Alkylidenyl Carbaporphyrinoids
Authors: Lee Chang-Hee 
Published: February 2020

We developed new class of porphyrinoids and core-modified porphyrinoids that have not been well studied previously. So called, meso-alkylidenyl porphyrins and their congeners are rather recently developed porphyrinoid family that have shown several unique properties including tautomerization, unusual protonation selectivity and spectroscopic properties. We here report the chemistry of meso-diethyl malonylidene-(m-benzi)porphyrin and meso-diethyl malonylidene-(m-benzi)pentaphyrins such the reaction with in-situ generated azomethine ylides and redox reactions. This 1,3-dipolar cycloaddition reaction has well documented and become an important alternative to the synthesis of pi-extended porphyrin analogs. The versatility and synthetic utilities associated with these reactions is useful in the synthesis of pi-extended analogs of the meso-alkylidenyl porphyrinoids. Successive 1,3-dipolar cycloaddition reaction combined with oxidation could be good tool for the pi-extended porphyrin analogs bearing region-selectively fused pyrrole rings. The 1,3-dipolar cycloaddition of the corresponding Pd(II) complexes also resulted in bis-cyclized adducts which are resistant to DDQ oxidation. All adducts are liable to core N-methylation. The adducts exhibit large bathochromic shift of absorption.
References 1. E.-K. Sim, S.-D. Jeong, D.-W. Yoon, S.-J. Hong, Y. Kang and C.-H. Lee, Org. Lett., 2006, 8, 3355–3358. 2. S.-D. Jeong, S.-J. Hong, K.-J. Park, S. Ham, J. L. Sessler, V. M. Lynch and C.-H. Lee, J. Org. Chem. 2007, 72, 6232–6240. 3. S.-D. Jeong, K.-J. Park, H.-J. Kim and C.-H. Lee, Chem. Commun. 2009, 5877–5879. 4. S.-D Jeong; A. Nowak-Kro; Y. Kim; S.-J. Kim; D. T. Gryko; C.-H. Lee, Chem. Commun. 2010, 46, 8737–8739. 5. J. Yoo; H.-J. Kim; H.-J. Kim; C.-H. Lee, J. Porphyrins Phthalocyanines, 2011, 15, 676–677. 6. D. Park, S.-D. Jeong, M. Ishida and C.-H. Lee, Chem. Commun. 2014, 50, 9277-9281. 7. D. Park, N.-Y. Choi, S.-J. Hong and Chang-Hee Lee, Chem. Commun., 2014, 50, 3689-3691.

Figure 1
Functionalization of the Corrole Ring: A Neverending Game
Authors: Paolesse Roberto , Nardis Sara , Monti Donato , Mandoj Federica , Pomarico Giuseppe , Naitana Mario Luigi , Di Natale Corrado , Stefanelli Manuela 
Published: February 2020

Corrole has been one of the first porphyrinoids reported in the literature, but only in the last few years it has been observed an impressive boost in corrole researches, because it has shown some peculiar properties, different from those of the corresponding porphyrins, which are promising for practical applications.
From this point of view, it has been important to study the possible synthetic modifications of the corrole framework, with the aim to tune the properties of the resulting macrocycle to the corresponding application.
Although the impressive progress of the corrole preprative chemistry, the functionalization of this macrocycle is still a challenging research area.
We have contributed to this area by studying the definition of synthetic protocols for the insertion of different substituents, both into the meso and b-positions of the macrocycle, with the aim of building more complex structures.
In these reaction, corrole has demonstrated a peculiar regioselectivity, with the substituents introduced in the directly linked pyrroles A and D. However we have recently observed that the substitution pattern can be modulated by the different substituents introduced in the peripheral positions.
In the present work we summarise our recent achievements in the functionalization of the corrole ring.
Ion-Pairing Assemblies Comprising Pyrrole-Based π-Electronic Systems
Authors: Maeda Hiromitsu 
Published: February 2020

π-Electronic systems responsive to metal ions and anions are very fascinating because they can form a variety of ion complexes as building subunits, providing supramolecular assemblies that exhibit attractive electronic and electrooptical properties.1 In fact, anion complexes of the anion-responsive π-systems have been found to construct ion-pair-based assembled structures as crystals, supramolecular gels, and thermotropic liquid crystals by combination with cationic species. Derived from favorable overlap of charged π-planes, ion-pair-based materials with the contribution of charge-segregated arrangements provided charge carrier mobilities, which are often larger than corresponding charge-by-charge-based materials, showing superior semi-conductive properties. Highly ordered arrangement of charged species, not only the ion complexes but also charged π-systems, has been found to be a key factor to exhibit the enhanced performance as fascinating electronic materials.
1. A recent review: Maeda, H. Bull. Chem. Soc. Jpn.
2013, 86, 1359–1399.
Synthesis of Phthalocyanines Using Triorganoindium Reagents
Authors: Fernández-Lázaro Fernando , Font-Sanchis Enrique , Molina Desiré , Sastre-Santos Angela 
Published: February 2020

Phthalocyanines (Pcs) have attracted much attention due to their singular electronic properties, exceptional chemical and photochemical stabilities, and strong absorption of visible light [1]. Although there is a great variety of methods for the preparation of substituted phthalocyanines, introducing the substituents either on the phthalonitrile precursor or on the already formed phthalocyanine core, we have decided to explore the palladium-catalysed coupling reaction between haloaromatics and triorganoindium reagents [2]. The latter benefits from high reactivity, efficiency, versatility and chemoselectivity, together with the low toxicity associated with indium derivatives. We have indeed already experimented with this process, first exploring some basics about the scope [3] and new procedures for the synthesis of the triorganoindium reagents [4], and later using it in the preparation of hole transporting materials [5]. In this occasion we will discuss our more recent results in the preparation of substituted phthalocyanines using triorganoindium reagents.
Taking advantage of the previously commented properties of Pcs, the synthesized compounds are excellent candidates for the preparation of photovoltaic devices, either Dye-Sensitized Solar Cells (DSSCs) or Bulk Heterojunction (BHJs) [6,7].

Acknowledgements. This work has been supported by the Spanish Ministerio de Economía y Competitividad, Generalitat Valenciana and the European FEDER funds (grants CTQ 2010-20349, CTQ2011-26455, CTQ2013-47922-R, PROMETEO 2012/010 and ISIC/2012/008).
References

Phthalocyanines: Properties and Applications, Leznoff, C. C.; Lever, A, B. P. Eds.; VCH Publishers, Weinheim, 1990-1996, Vols. 1-4.

Pérez, I.; Pérez-Sestelo, J.; Sarandeses, L. A. Org. Lett.
1999, 1, 1267-1269.

Font-Sanchis, E.; Céspedes-Guirao, F. J.; Sastre-Santos, A.; Fernández-Lázaro, F. J. Org. Chem.
2007, 72, 3589-3591.

Font-Sanchis, E.; Sastre-Santos, A.; Fernández-Lázaro, F. Dalton Trans.
2009, 2470-2473.

Lana-Villareal, T.; Font-Sanchis, E.; Sastre-Santos, A.; Fernández-Lázaro, F.; Gómez, R. ChemPhysChem
2011, 12, 1155-1164.

Martín-Gomis, L.; Fernández-Lázaro, F.; Sastre-Santos, A. J. Mater. Chem. A
2014, 2, 15672-15682.

Molina, D.; Guerrero, A.; García-Belmonte, G.; Fernández-Lázaro, F.; Sastre-Santos, A. Eur.
J. Org. Chem.
2014, 4585-4591.

Figure 1
Bioinspired CO2 Reduction with Iron Porphyrin Catalysts in High Efficiency
Authors: Naruta Yoshinori 
Published: February 2020

Conversion of CO2 to useful carbon resources as well as water splitting is the important ways to store renewable energy as chemical energy. Both reactions are typical multi-electron ones, thus, they tend to require large overpotentials (or activation energies) unless one uses proper catalysts. Particulary, CO2 reduction potentially gives several reduced products, CO, HCO2H, (CO2H)2, CH3OH, etc. CO2 reduction also competes proton reduction. Thus, the product selectivity is another important factor on its reaction. Following issues are keys on the development of CO2 reduction catalysts: (1) low overpotential, (2) high turnover frequency, (3) robustness, (4) product selectivity, (5) easy separation of product(s), and (6) use of base metal (complexes) on the elemental strategy aspect. Carbon monoxide dehydrogenase (CODH), an enzyme in bacteria, catalyzes the mutual conversions between CO2 and CO. The active site of the enzyme is consisted of Ni-Fe cluster and this enzyme realizes selective CO2 reduction to CO at very low overpotential (η < 100 mV). We develop new catalysts to fulfill the above criteria referring the enzyme structure. We developed iron porphyrin dimers as bio-inspired catalysts, which realized electrochemical CO2 reduction at the lowest overpotentials and high TOF in high selectivity and robustness by choosing suitable functional groups. In a homogeneous solution, continuous electrocatalytic reduction of CO2 for 12 h gave a good Faradaic efficiency as well as a good product selectivity by keeping a constant current through the electrolysis and any decrease of the catalyst activity is not observed. We will discuss the importance of the dinuclear center in the CO2 reduction.
Solid-State Electrochemistry of Organic Macrocycles and Mofs; Application to Organic Electronics and Energy Storage
Authors: Awaga Kunio 
Published: February 2020

Solid-state electrochemistry is a powerful tool to control the electronic properties of organic materials through charge/carrier injections. In contrast to the numerous studies on organic polymers, its application to small molecules has been limited, because most of them become soluble into solvents after redox reactions. In this perspective, the organic macrocycles and MOFs are promising materials due to their structural robustness. We will discuss the following three topics
1. Electric-double-layer field-effect transistors of organic macrocycles. Electric-double-layers (EDLs), formed at solid-electrolyte interfaces, induce extremely large electric fields. This results in a high charge carrier accumulation in the solid, much more effectively than solid dielectric materials. We investigated the EDL thin-film transisotrs of porphyrazines and octathio[8]circulene (sulflower) with gate dielectrics of ionic liquids, which have attracted much attention due to their wide electrochemical windows, low vapor pressures, etc. We revealed the factors, controlling the mobility and threshold voltage in these types of FETs.
2. Electrochemical doping to nano-porous single crystals of Li-phthalocyanine (LiPc). The crystal structure of a neutral π radical, LiPc in the x from, consists of 1D stacking chains of LiPc and nano-channels parallel to them. We found that the LiPc crystals were electrochemically oxidized in an acetonitrile solution of tetrabutyl ammonium chloride (TBA·Cl), exhibiting a crystal-to-crystal transformation to LiPc·Cl
x
(0<x<0.5). The crystal structures of the LiPc·Cl
x
series were successfully solved and refined by the X-ray single-crystal analysis, and the obtained structures clearly indicated the presence of the Cl−ions in the 1D channels and a systematic structural change in the π stacking chain of LiPc.
3. Synthesis and solid-state electrochemistry of a redox-active MOF, Cu(2,7-AQDC), toward high-capacity lithium battery. We synthesized a microporous redox-active MOF, Cu(2,7-AQDC) (2,7-H2AQDC=2,7-anthraquinonedicarboxylic acid), and utilized it as a cathode active material in lithium batteries. With a voltage window of 4.0-1.7 V, both metal clusters and anthraquinone groups in the ligands were found to exhibit reversible redox activity. By controlling the voltage window of operation, extremely high recyclability of batteries was achieved.
Copper Nanoparticles Effect on the Corrosion Behavior of Different Types of Nickel-Based Super Alloys
Authors: Abdullah Aboubakr Moustafa , Mohamed Adel M. A. , Sliem Mostafa H 
Published: February 2020

Nickel-based alloys are usually used for a wide range of applications like petrochemical processing, oil and gas extraction, marine engineering and high temperature applications in power generation industry e.g., heat exchangers or turbine blades due to their excellent corrosion resistance and good mechanical properties. Nickel-based alloys are designed to resist high loading and severe corrosive environments during operations.
The aim of this study is to investigate the effect of depositing copper nanoparticles of different sizes on top of the surface of different nickel-based alloys (e.g.alloys 825, 625 and 276) on their corrosion behavior in different electrolytes of different pH values and chloride and sulfide ions concentrations. The study included, electrochemical and non-electrochemical characterization techniques. Also, the surfaces of the corroded alloys were checked using optical and scanning electron microscopy, energy dispersive x-ray and atomic force microscopy.
Inhibition Effect of Some Benzotriazole Derivatives on Carbon Steel in 1M H2so4 Medium
Authors: Branzoi Florina , Pacuretu Catalina , Branzoi Roxana 
Published: February 2020

The inhibition effect of some benzotriazole derivatives (1-hydroxybenzotriazole, 5-chlorobenzotriazole and 3-amino-5-mercapto-1,2,4-triazole) on the corrosion of two carbon steels (OL 37 and OLC 45) in 1M H2SO4 was studied potentiostatic and potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and metallurgical microscopy techniques.
The inhibition activity analysis of these organic inhibitors was made by assuming that the mechanism of inhibition by organic molecules is chemisorptions and that the energetic of the corrosion process per se is unaffected by the addition of substituents on the parent compound. We presume that, these organic inhibitors inhibit corrosion of carbon steel by a protective mechanism, forming insoluble iron complexes and repairing the porous oxide layers. The addition of the organic inhibitors led in all the cases to inhibition of the corrosion process. Polarization curves indicate that they are mixed type of inhibitors. The inhibition efficiency was high in all the studied cases. The corrosion parameters obtained from polarization curves and from EIS spectra are in good concordance and point out the inhibitory action of derivatives benzotriazole. The adsorptions of the organic compounds on the carbon steels surface obeyed Langmuir’s isotherm. The thermodynamic parameters of adsorption enthalpy (ΔH0), adsorption free energy (ΔG0) and adsorption entropy (ΔS0) were calculated. Further characterization using Fourier transform infrared spectroscopy (FT-IR) demonstrates the adsorption of organic inhibitors and the formation of corrosion products on the carbon steels surface. The inhibition process was attributed to the formation of the adsorbed film on the metal surface that protects the metal against corrosive agents. The EIS measurements have confirmed this protection and pointed out the formation of adsorption layers on the electrode surface.