bluuebunny/crossref_metadata_2025_split huggingface dataset:
SEI Characterization Using Ferrocene/Ferrocenium As Redox Shuttle
Authors: Dinh Nguyen Minh-Thu , Delacourt Charles 
Published: February 2020

The characterisation of the solid electrolyte interphase (SEI) formed at the negative electrode in lithium-ion batteries is proposed by Tang et al. 1 Its principle is to introduce a redox shuttle in the electrolyte after the passive film (SEI) is formed at the electrode surface and to study how the electrochemistry of the shuttle is modified by the presence of the film. It is then possible to derive some film properties such those related to the transport of the redox molecule in the film and those related to the kinetics of the shuttle oxidation/reduction. So far, the majority of the work on shuttle experiments was done on a glassy carbon electrode using ferrocene/ferrocenium as redox shuttle.
In this communication, we will describe experiments dedicated to form SEIs at glassy carbon electrodes and provide details on shuttle characterization experiments. We will show that the electrochemistry of the ferrocene/ferrocenium couple is greatly dependent on the formation charge involved in the SEI formation step. The SEI both slows down the kinetics of ferrocenium reduction (low overpotential) and also has an effect on the value of the limiting current density (high overpotential). For thin SEIs, there is a marked influence of the current density with the electrode rotation rate. Koutecky-Levich analysis can be performed on these data in order to derive the so-called kinetic current density. For electrodes on which “thick” SEIs are grown, the current density for ferrocenium reduction is much smaller and much less sensitive to the electrode rotation rate, which indicates that there is little ferrocenium diffusion limitations in the electrolyte at this low current density value. Performing Koutecky Levich analysis on these data is not possible, but the current density value measured at the RDE somehow can be considered as a direct reading of the kinetic current density.
Acknowlegdment: This work was supported by the European Union’s 7th Framework programme for research, technological development and demonstration under the SIRBATT project, which has received agreement No. 608502.
References:

Tang, M.; Newman, J. J. Electrochem. Soc.
2011, 158(5), A530.
Unraveling the Chemical/Structural Degradation Mechanisms of Graphite/SEI in the Presence of Dissolved Manganese Ions in Lithium-Ion Batteries
Authors: Shin Hosop , Park Jonghyun , Lu Wei , Sastry Ann Marie 
Published: February 2020

Understanding the degradation mechanisms of a Li-ion battery is of considerable importance for achieving a longer battery lifetime. In a Li-ion battery, the degradation process involves several physical, mechanical, and chemical processes that are interdependent. The complexity of these degradation mechanisms makes it difficult to improve the performance degradation of the battery over time, especially at elevated temperatures. Among various other reasons, the dissolution of active materials at the cathode and the resultant presence of transition metal ions in the vicinity of the anode/SEI are two of the key phenomena responsible for the degradation. While the dissolution at the cathode is effectively suppressed by the surface coating and the doping of the active materials, the degradation that occurs at the anode/SEI still remains the main challenge for Li-ion batteries due to the presence of transition metal ions (especially manganese ions). Thus, it is essential to understand how dissolved manganese ions contribute to the degradation of the anode/SEI.
Although it is obvious that the deposition of dissolved manganese ions occurs on the anode side, the nature of the precise mechanism of the interaction between the dissolved manganese ions and the anode/SEI is still being debated. In addition, the effect of dissolved manganese ions on the structural degradation of graphitic anode has not yet been systematically investigated, even if recent studies have reported the presence of manganese compounds near the graphite surface and within the graphite due to cracks or defects.
In this work, we first show how the chemical degradation of the SEI is caused by deposited manganese compounds and where the manganese is significantly distributed at the graphite/SEI. We also demonstrate that the ion-exchange reaction mechanism between inorganic SEI species and manganese ions occurs and that the identified manganese compounds at the SEI are the result of the reaction. In addition, we reveal that the surface structural disordering of the graphitic anode can be caused by dissolved manganese ions that are diffused through cracks or defects in the graphite/SEI. Density function theory (DFT) calculations are used to explain the structural effect of co-intercalated manganese ions into the graphite anode. This work sheds further light on the mechanism of capacity fading as driven by deposited manganese compounds at the anode/SEI.
(Invited) Phosphorus Complexes of Corrole
Authors: Paolesse Roberto , Naitana Mario Luigi , Nardis Sara , Pomarico Giuseppe , Stefanelli Manuela , Mandoj Federica 
Published: February 2020

Metal complexes of corrole continue to attract the interest of different research groups, since the coordination chemistry of such a macrocycle presents peculiar and intriguing characteristics, such as for example its non-innocent character as a ligand.
The Periodic Table of Metallocorrolates has been widely expanded in recent years, including also main group elements. Among them, phosphorus complexes of corrole have been of particular interest, since these compounds can be easily prepared in good yields, are stable, and show unusual optical properties. For these reasons, phosphorus corroles represent a class of interesting compounds to be exploited in the field of material science or for biomedical investigations and the definition of synthetic pathways for their functionalization is an important step to optimize their properties for various applications.
We have recently developed different pathway for the selective introduction of different substituents in the peripheral positions of phosphorus triarylcorrole complexes. The characterization of such a complexes showed some peculiar properties, such as for example an unusual ruffled geometry of the corrole core, a conformation that has not been considered possible for such a macrocycle.
(Invited) Pyrrole-Based Ion-Pairing Supramolecular Assemblies
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 pyrrole-based π-systems, such as dipyrrolyldiketone boron complexes and related molecules, have been found to construct ion-pairing assembled structures as solution-state aggregates, crystals, supramolecular gels, and thermotropic liquid crystals by combination with cationic species. Derived from favorable overlap of charged π-planes, ion-pairing assemblies with the contribution of charge-segregated arrangements provided charge carrier mobilities, which are often larger than corresponding charge-by-charge-based assemblies, showing superior semi-conductive properties. Recent achievements in arylethynyl-substituted derivatives include the formation of a variety of highly ordered structures, such as totally charge-segregated assemblies, based on [2+1]-type interlocked and [1+1]-type planar anion complexes.[2]

1. A review: Maeda, H. Bull. Chem. Soc. Jpn.
2013, 86, 1359–1399.
2. Yamakado, R.; Sakurai, T.; Matsuda, W.; Seki, S.; Yasuda, N.; Akine, S.; Maeda, H. Chem. Eur. J. in press (DOI: 10.1002/chem.201503654).
(Invited) Photodynamic Inactivation of Natural Environmental Biofilm Forming Microorganisms on Surfaces
Authors: Roeder Beate , Preuß Annegret , Borhuetter Tobias 
Published: February 2020

Biofilms on outdoor walls cause aesthetic problems and economic damage. Therefore, facade paints often-containing biocides. However, commercial available biocides may have a series of adverse effects on living organisms as well as harmful environmental effects. Furthermore, biocides are increasingly designed to be more effective and are environmentally persistent. Thus, an eco-friendly and non-harmful to human health alternative to conventional biocides in wall color is strongly recommended.
This study was performed as a proof of concept for singlet oxygen generating facade paint as an alternative to conventional biocide containing facade paint for the prevention of biofilm growth on outdoor walls.
The well-known photosensitizer 5,10,15,20-tetrakis(N-methyl-4-pyridyl)-21H,23H-porphine (TMPyP) was used as an additive in a commercially available facade paint. The generation of singlet molecular oxygen was shown using time resolved 2D measurements of the singlet oxygen luminescence. Using phototoxicity tests, we demonstrated the photodynamic activity of the photosensitizer against defined mold fungi and a mixture of microorganisms harvested from native outdoor biofilms on surfaces.
It was proven in general that it is possible to inhibit the growth of biofilm forming microorganisms growing on solid wall paint surfaces by the cationic photosensitizer TMPyP added to the facade paint using daylight conditions for illumination in 12 hours light and dark cycles.

Figure: Singlet oxygen luminescence scan of microorganisms incubated with the PS with TMPyP. The intensity plot, which is overlayed with the picture of the sample, shows the amplitude of singlet oxygen luminescence

Figure 1
(Invited) Iron Porphyrin Alcoholate and Manganese Porphyrin Thiolate As Element-Substituted Analogs of Heme Thiolate Complex
Authors: Higuchi Tsunehiko 
Published: February 2020

Cytochrome P450 plays a central role in drug metabolism and steroid biosynthesis. Among heme enzymes, cytochrome P450 and NO synthase (NOS) have strong oxidizing ability and unusual structure, in that their heme iron has thiolate coordination. We previously succeeded in synthesizing the first synthetic heme thiolate (SR complex)1 which retains thiolate coordination during catalytic oxidation and found several remarkable axial ligand effects on catalytic oxidation. However, alcoholate and selenolate ligand, which are belonged to chalcogen group same as thiolate, have not ever been examined for researching such relative effect of axial ligand by us and other investigators. Manganese porphyrin coordinated by alkanethiolate also has not yet been reported as an isolated form.
Now we prepared the first isolable heme alcoholate 1, heme selenolate 2 and manganese heme thiolate 3 in order to investigate the effect of elemental substitution on SR complex on spectroscopic and catalytic properties. We have succeeded in the synthesis of the first heme-alcoholate complexes and the first manganese porphyrin coordinated by thiolate that can retain axial coordination during catalytic oxidizing reaction. We obtained UV-Vis spectra, FT-IR and EPR spectra of these complexes. The N-O stretching mode of complex 1-NO was 60 cm-1 higher than that of SR-NO and 38 cm-1 lower than that of an alcohol-ligated heme2. Complex 1 had 0.2 V higher E1/2 (Fe(II)/Fe(III)) than that of SR complex. These two results indicate that electron donative ability of alcoholate is much less than that of thiolate. Catalytic activity of 1 was much lower than that of SR on the oxidation of 2,4,6-tri-tert-butylphenol with perphenylacetic acid, whereas, catalytic activity of complex 3 was comparable to that of SR.
References
1. a) T. Higuchi, S. Uzu, M. Hirobe, J. Am. Chem. Soc.
1990, 112, 7051-53; b) T. Higuchi, K. Shimada, N. Maruyama, M. Hirobe, J. Am. Chem. Soc.
1993, 115, 7551-7552; c) Y. Urano, T. Higuchi, M. Hirobe, T. Nagano, J. Am. Chem. Soc.
1997, 119, 12008-12009; d) N. Suzuki, T. Higuchi, Y. Urano, K. Kikuchi, H. Uekusa, Y. Ohashi, T. Uchida, T. Kitagawa, T. Nagano, J. Am. Chem. Soc.
1999, 121, 11571-11572; e) T. Ohno, N. Suzuki, T. Dokoh, Y. Urano, K. Kikuchi, M. Hirobe, T. Higuchi, T. Nagano, J. Inorg. Biochem. 2000, 82, 123-125; f) N. Suzuki, T. Higuchi, T. Nagano, J. Am. Chem. Soc.
2002, 124, 9622-9628. g) T. Yamane, K. Makino, N. Umezawa, N. Kato, T. Higuchi Angew. Chem. Int. Ed.
2008, 47, 6438.
2. Yi, G.-B; Chen, L.; Khan, M. A.; Richter-Addo, G. B. Inorg. Chem. 1997, 36, 3876.

Figure 1
(Invited) Peripherally Fused Azabodipy Dimers: A New Class of Near-Infrared Fluorescence Probes
Authors: D'Souza Francis , Bandi Venugopal , Gobeze Haptom B. 
Published: February 2020

Photosensitizers with absorption and emission in the near-infrared (near-IR) spectral region are of great importance for diverse applications including artificial photosynthesis, high-contrast bioimaging, optical recording, near-IR laser filter, near-IR photography, photodynamic therapy and solar cells. For example, for solar cell application, sensitizers possessing light energy harvesting capability not only in the UV-visible region but also in the near-IR region where sunlight carries over 50% of its radiation are highly desired. Additionally, the near-IR sensitizers show marked advantages over traditionally used visible sensitizers including their ability of low light scattering and background interference, and deeper light penetration in tissues, making them the highly sought out probes in bioimaging. However, these near-IR probes often suffer from shorter excited state lifetimes and lower fluorescence quantum yields. Hence, there is a pressing need to develop near-IR probes exhibiting higher excited state lifetime and quantum yields, accompanied by better thermal and photostability.
In the present study, we have overcome this obstacle and report a multi-step syntheses of a series of peripherally fused azaBODIPY dimers revealing fluorescence in the near-IR region (see Scheme 1 for structures). Additionally, owing to the imposed structural rigidity (as a result of utilization of two of the peripheral aryl substituents to fuse the azaBODIPY macrocycles), the fluorescence lifetimes and quantum yields of the azaBODIPY dimers are found to be higher than their corresponding monomer analogs; thus, offering their potential utility in a range of photonic/biophotonic applications. Details of these findings are summarized below.

Figure 1
Synthesis and Characterization of A2B2 Tetrabenzoporphyrins
Authors: Kumar Siddhartha , Wang Hong 
Published: February 2020

Benzoporphyrins have been investigated for use in a variety of applications such as dye-sensitized solar cells, photodynamic therapy and organic electronic materials1. A2B2 type porphyrins are known to exhibit non-linear optical properties2. However, there are no reports in literature of tetrabenzofused A2B2 porphyrin systems.
In this work we have synthesized novel A2B2 tetrabenzoporphyrins with electron donors on one axis and electron acceptors on the other axis. We also synthesized the corresponding A2 dibenzoporphyrins for comparison of the optical and electronic properties with the A2B2 tetrabenzoporphyrins.
(1) Myśliwiec, D.; Donnio, B.; Chmielewski, P. J.; Heinrich, B.; Stępień, M. Journal of the American Chemical Society
2012, 134, 4822.
(2) Nowak-Król, A.; Wilson, C. J.; Drobizhev, M.; Kondratuk, D. V.; Rebane, A.; Anderson, H. L.; Gryko, D. T. ChemPhysChem
2012, 13, 3966.
(3) (2) Senge, M. O.; Fazekas, M.; Pintea, M.; Zawadzka, M.; Blau, W. J. European Journal of Organic Chemistry 2011, 2011, 5797.

Figure 1
(Invited) Low Frequency Modes of Porphyrin Systems
Authors: Schünemann Volker 
Published: February 2020

Nuclear resonance scattering is an ideal tool to study electronic and dynamic properties of iron centers in chemical and biological systems. During the last years Nuclear Resonance Vibrational Spectroscopy (NRVS) also called Nuclear Inelastic Scattering (NIS) has been used to detect iron based vibrational modes heme proteins and model complexes. We have investigated the vibrational modes of the heme model complex [TPPFeIII(NH2Pz)2]Cl [1], both experimentally via NRVS and theoretically by density functional theory (DFT) calculations in the region from ~5 to ~800 cm-1. DFT calculations coupled with molecular mechanics allow to investigate solvent effects. First preliminary calculations show, that the vibrational modes of [TPPFeIII(NH2Pz)2]Cl are not significantly influenced by the solvent. In addition the effect of solvent on the low frequency modes of the NO transporter protein nitrophorin [2,3] will be presented.
This work has been supported by the research initiative NANOKAT and by the German Federal Ministry of Education and Research.
[1] V. Schünemann, A.M. Raitsimring, R. Benda, A.X. Trautwein, T.K. Shokireva, F.A. Walker, JBIC 4 (1999) 708-716.
[2] B. Moeser, A. Janoschka, J.A. Wolny, H. Paulsen, I. Fillipov, R.E. Berry, H. Zhang, A.I. Chumakov, F.A. Walker, V. Schünemann, J. Am. Chem. Soc. 134(9) (2012) 4216-4228.
[3] H. Auerbach, I. Faus, S. Rackwitz, J.A. Wolny, F.A. Walker, A.I. Chumakov, H. Ogata, M. Knipp, V. Schünemann, Hyperfine Interact. 226 (2014) 439-443.
(Invited) Structure and Function of Heme Acquisition System in Corynebacterium Glutamicum
Authors: Aono Shigetoshi 
Published: February 2020

Most commensal or pathogenic bacteria have heme acquisition systems for utilizing host heme as an iron source. The heme acquisition systems consist of cell surface localized heme binding proteins and heme transport proteins. In several Gram-positive bacteria such as Staphylococcus aureus and Bacillus anthracis, the iron regulated surface determinant (Isd) proteins capture and transfer heme to ABC transporter-type heme transport proteins. Though a similar ABC-type heme transporter consisting of HmuT, HmuU, and HmuV proteins is used by Corynebacteria glutamicum and Corynebacterium diphtheriae, they adopt different heme binding proteins, HtaA and HtaB, instead of Isd proteins. The ABC-type heme transporter system is widely used for heme acquisition, which consists of an ATP-binding protein, heme permease, and heme-binding protein (substrate-binding protein). In this work, we have studied the structural and functional relationships of two heme-binding proteins, HtaA and HmuT in Corynebacterium glutamicum. HtaA and HmuT act as a heme-binding protein in the heme acquisition system of HtaAB-HmuTUV for Corynebacterium glutamicum. Heme captured in HtaA is transferred into cytoplasm by the ABC-type HmuUV heme transporter, but the detailed molecular mechanisms of heme transport in these systems remain to be elucidated. In this work, the molecular mechanisms of heme acquisition in Corynebacterium glutamicum were elucidated based on the structural analyses of HtaA and HmuT.
We determined the crystal structures of an N-terminal domain of HtaA (HtaA-N) and HmuT (CgHmuT) from C. glutamicum. Although the amino acid sequence of HtaA-N is not similar to those of Isd proteins, HtaA-N has a similar β-sandwich structure to the NEAT-domains of Isd proteins. In HtaA-N, a single heme molecule is bound in a hydrophobic pocket with Tyr58 as the axial ligand.
CgHmuT consists of structurally similar two domains located in the N-terminal and C-terminal regions. A single heme molecule is bound in the cleft between these domains. Heme iron is ligated by His141 and Tyr240. The details of heme environmental structure of heme-bound HmuT revealed by resonance Raman spectroscopy will be discussed.
Development of Pyrolyzed Nanoporous Carbon Electrodes with Sponge-like Networks of Mesopores for Use as Supercapacitors
Authors: Lim Yeongjin , Joo Sang Hoon , Shin Heungjoo 
Published: February 2020

We developed patternable nanoporous carbon microstructures fabricated using simple O2 plasma etching and carbon-MEMS for the application of supercapacitors. Carbon-MEMS is a versatile microfabrication technology enabling batch fabrication of micro-/nano-sized carbon structure of complex architecture at a wafer level using conventional UV-lithography and pyrolysis processes. By incorporating a simple O2 plasma etching process prior to the pyrolysis process, sponge-like networks of mesopores and nanoporous surface are formed on the top surface of pre-patterned SU-8 negative photoresist structures due to self-masking effect. These O2-plasma-treated photoresist structures are converted into nanoporous glassy carbon electrodes (average pore size = 0.56 – 0.71 nm) with sponge-like networks of mesopores via pyrolysis without using any complex nanofabrication process. As a result, the surface area and electrochemical capacitance of the nanoporous carbon surface are increased up to ~ 795 (surface area = ~ 994 m2∙g-1) and ~ 29.6 times (24.1 mF∙cm-2 at 5 mV/s) respectively compared to a bare carbon surface. In addition, arrays of 3D nanoporous carbon micro-structures such as cylinders can be simply integrated on the planar carbon electrode surface by adding a photoresist patterning process enabling further capacitance improvement up to 41.9 times. The pore size and surface morphology of the nanoporous carbon are controllable depending on O2 plasma etching time.
The Impact of Stress-Strain States on Hydrogen Flux in Martensitic Steels
Authors: Guedes Daniella , Cohendoz Stephane , Oudriss Abdelali , Bouhattate Jamaa , Thebault Florian , Creus Juan , Feaugas Xavier 
Published: February 2020

The role of stress-strain states in hydrogen distribution, concentration and mobility on martensitic steel is outlined by performing tensile tests until fracture on flat, smooth, tensile specimens under simultaneous electrochemical permeation test. A specific device was designed in order to combined mechanical and electrochemical permeation (EP) experiments. Hydrogen charging was performed in sulfuric acid solution and the hydrogen detection was performed in NaOH solution.
It is demonstrated that hydrogen state can be influenced by elastic distortion at different microstructural scales related to mechanical defects (vacancies, dislocations), metallurgical components (grain boundaries, precipitates), internal and applied constraints. In additional, the mobile dislocations increase the hydrogen flux in relation with a drag process and the storage dislocations decrease the hydrogen flux in accordance with a trapping mechanism.
Effects of Hydrogen on the Surface Films Formed on Iron in Pure Water at Various Temperatures
Authors: Ejaz Ahsan , Xiao Qian , Chen Junjie , Han Guangdong , Lu Zhanpeng 
Published: February 2020

The effects of hydrogen on the types, morphologies and electrochemical properties of the surface films formed on iron in aerated pure water at 25, 40, 50 and 70 oC were investigated by by using optical microscopy, X-ray diffraction measurements, Raman spectroscopy, electrochemical impedance spectroscopy (EIS) and Mott-Schottky (M-S) plots. Increasing temperature from 25 oC to 70 oC significantly accelerated the corrosion of non-charged iron. Figure 1 shows that yellow rust formed on the non-charged iron after immersion 21h at 40 oC, while the surface of hydrogen-charged iron after immersion in the same condition was gray. Figure 2 shows that the film formed on the non-charged iron after immersion 21h at 70 oC was dark, while the surface of hydrogen-charged iron after immersion in the same condition was covered with loosely distributed yellow rust particles. Raman spectra showed the different compositions of formed films on non-charged and hydrogen-charged iron specimens, as shown in Fig. 3. Normally the high valence iron oxides were formed on non-charged iron while relative low valence iron oxides were formed on the hydrogen-charged iron, with exceptions. The stability and semiconductor properties of the surface films formed on non-charged and hydrogen-charged specimens were characterized by EIS and M-S plot measurements in boric acid-borate buffere solutions, showing significant effect of hydrogen.

Figure 1