bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Improved Interfaces in Multilayered Organic-Inorganic Hybrid Solar Cells with π-Conjugated Polymers-Antimony Sulfide-Strontium Titanate-Titanium Oxide
Authors: Yukawa Mayumi , Hayakawa Akinobu , Sagawa Takashi 
Published: February 2020

We have developed various organic-inorganic hybrid solar cells using Sb2S3-based composites with π-electronic molecules [1,2]. For examples, utilization of zinc phthalocyanine (ZnPC) for the hybrid solar cell composed of glass/indium-tin-oxide (ITO)/TiO2/Sb2S3/ZnPC/Au achieved long durability with keeping the relative power conversion efficiency (PCE) of 90% after the stability test under 1 sun at 63 °C at a relative humidity of 50% for 1,500 h [1]. Using La-decorated Sb2S3 for hybrid solar cell composed of glass/F-doped SnO2 (FTO)/TiO2/La-decorated Sb2S3/poly[(3-hexylthiophene)-2,5-diyl] (P3HT)/poly[3-(3-carboxypropyl)thiophene-2,5-diyl] (P3CT)/Au resulted in 33% improvement of PCE as compared to that of the non-decorated Sb2S3 because of lowering the resistance at the interface, which was confirmed by the impedance analyses [2]. While doping of Zn into Sb2S3 attained 57% enhancement of PCE. This result is ascribed to the effective lowering the bulk-resistance [2]. In this context, we newly inserted SrTiO3 layer between TiO2 and Sb2S3 interface and found the enhancement of the open circuit voltage (VOC
) from 0.61 V to 0.74 V. Temperature dependence of VOC
for SrTiO3-inserted device indicated the maximum voltage was 1.7 V, which had been estimated by extrapolation of the line to 0 K. For further improvement of the photovoltaic performance, we modified the thin-film making process for Sb2S3 layer from the previously reported procedures [1,2]. After the spin-coating of the precursor solution of SbCl3-thiourea complex in DMF onto the SrTiO3 layer, heat treatment at 220 °C under vacuum was newly performed. The thickness, surface roughness, and sea-island structure were optimized by their uv-vis measurement, AFM, TEM observations, and current density-voltage (J-V) characteristics in terms of transmittance, reflectivity, and short circuit current density (JSC
) by changing the spin-coating speed, duration of heating, and so on. Through the optimization, remarkable enhancement of JSC
from 10.7 mA cm-2 to 13.6 mA cm-2 and improvement of PCE from 4.7% to 6.1% were achieved.
[1] A. Hayakawa, M. Yukawa, and T. Sagawa, ECS J. Solid-State Technology, 6(4), Q35-Q38 (2017).
[2] M. Yukawa, A. Hayakawa, and T. Sagawa, ECS Trans., 77(11), 653-659 (2017).
(Invited) Carbon Nanotube and Porphyrins: Materials for Optics and Energy Applications
Authors: Hanana Manel , Delport Géraud , Le Gac Stéphane , Voisin Christophe , Jousselme Bruno , Boitrel Bernard , Lauret Jean-Sébastien , Campidelli Stephane 
Published: February 2020

The fabrication of functional hybrid materials that preserves and combines the properties of their building blocks is a central issue of nanosciences. Among the different classes of nanomaterials, carbon nanotubes are promising for electronics, opto-electronics, catalysis and composite applications. In this context the combination of nanotubes with porphyrins has been widely explored for catalytic1,2 or electron transfer purposes.3,4

Here I present two results obtained recently on the nanotube/porphyrin composites, the first deals with the supramolecular organization in micelles of porphyrins around the nanotubes.5 In this work we were able to explain the Davidoff splitting observed on the absorption bands of the porphyrins by their organization around the nanotubes. The second deals with the synergic effect on catalytic activity of carbon nanotubes and strapped iron porphyrin hybrids for Oxygen Reduction Reaction (ORR).6 In particular, we demonstrated that the combination of both components - MWNTs and porphyrin - leads to a better catalytic activity than those of the nanotubes or the porphyrins taken separately. This study highlights the importance of the carbon support for the catalysis. The nanotubes ensure the availability of electrons to the porphyrin catalysts and allow the ORR to occur via the 4-electron pathway, avoiding the production of hydrogen peroxide.
Reference List:
(1) McGuire Jr, R.; Dogutan, D. K.; Teets, T. S.; Suntivich, J.; Shao-Horn, Y.; Nocera, D. G. Chem. Sci.
2010, 1, 411-414.
(2) Hijazi, I.; Bourgeteau, T.; Cornut, R.; Morozan, A.; Filoramo, A.; Leroy, J.; Derycke, V.; Jousselme, B.; Campidelli, S. J. Am. Chem. Soc.
2014, 136, 6348-6354.
(3) Umeyama, T.; Imahori, H. J. Phys. Chem. C
2013, 117, 3195-3209.
(4) Dirian, K.; Herranz, M. A.; Katsukis, G.; Malig, J.; Rodríguez-Pérez, L.; Romero-Nieto, C.; Strauss, V.; Martín, N.; Guldi, D. M. Chem. Sci.
2013, 4, 4335-4353.
(5) Delport, G.; Vialla, F.; Roquelet, C.; Campidelli, S.; Voisin, C.; Lauret, J.-S. Nano Lett.
2017, 17, 6778-6782.
(6) Hanana, M.; Arcostanzo, H.; Bouget, M.; Das, P. K.; Le Gac, S.; Cornut, R.; Jousselme, B.; Boitrel, B.; Campidelli, S. submitted.
(Invited) Assembling Different Functional Molecules into Multifunctional, Crystalline, Molecular Solids
Authors: Wöll Christof 
Published: February 2020

Metal-organic frameworks (MOFs) carry a huge potential with regard to assembling different types of function organic and metal-organic molecules into multifunctional,hybrid, molecular solids. The field is presently getting quite mature, as demonstrate by several applications exploiting the electrical, electronic and photophysical properties of this rich class of porous, crystalline materials [1]. Recent examples are MOF-based electrochemical [2,3], photo-electrochemical [4] and photovoltaic devices [5,6], as well as photon-upconversion [7]. We have developed a layer-by-layer method to produce well-defined, highly oriented and monolithic MOF thin films supported on different types of surfaces, also referred to as SURMOFs [1]. This procedure in particular allows the fabrication of hetero-multilayers. The fabrication of such well-defined model systems will be described, as well as the results of detailed, multi-technique investigations of electrical [8] and photophysical properties exhibited by empty and loaded MOFs, including cyclic voltammetry, atomic force microscopy, quartz crystal microbalance and UV-Vis spectroscopy. We will discuss the huge size of the chemical space spanned by MOFs can propose that by loading MOFs with nanoparticles or quantum dots the potential is further extended. SURMOFs offer particular advantages in this context, since the loading can be integrated in the layer-by-layer method, offering the potential to fabricate hetero-mulitlayers.
References:
[1] J. Liu, Ch. Wöll, Chem. Soc. Rev. 46, 5681 (2017)
[2] A. Dragässer, O. Shekhah, O. Zybaylo, C. Shen, M. Buck, Ch. Wöll, D. Schlettwein, Chem. Comm., 48, 663 (2012)
[3] J. Liu, M. Paradinas, L. Heinke, M. Buck, C. Ocal, V. Mugnaini, Ch. Wöll
Chem.Elektro.Chem., 3, 713 (2016)
[4] Lu Ye, J. Liu, Y. Gao, Ch. Gong, M. Addicoat, Th. Heine, Ch. Wöll, L. Sun, Mater. Chem. A, 4, 15320, (2016)
[5] J. Liu, W. Zhou, J. Liu, I. Howard, G. Kilibarda, S. Schlabach, D. Coupry, M. Addicoat, S. Yoneda, Y. Tsutsui, T. Sakurai, S. Seki, Zh. Wang, P. Lindemann, E. Redel, Th. Heine, Ch. Wöll, Angew. Chemie Intl. Ed., 54, 7441 (2015)
[6] J. Liu, W. Zhou, J. Liu, Y. Fujimori, T. Higashino, H. Imahori, X. Jiang, J. Zhao, T. Sakurai, Y. Hattori, W. Matsuda, Shu Seki, S. K. Garlapati, S. Dasgupta, E. Redel, L. Sun, Ch. Wöll, Journal of Mat. Chem. A, 4, 12739 (2016)
[7] M. Oldenburg, A. Turshatov, D. Busko, S. Wollgarten, M. Adams, N. Baroni, A. Welle, E. Redel, Ch. Wöll, B. S. Richards, I. A. Howard, Adv. Mater., 28, 8477 (2016)
[8] J. Liu, T. Wächter, A. Irmler, P.G. Weidler, H. Gliemann, F. Pauly, V. Mugnaini, M. Zharnikov, Ch. Wöll, ACS Applied Materials & Interfaces, 7, 9824, (2015)
Formation of Hydrogen-Bonded Supramolecular Hetero-Triads with a Diprotonated Porphyrin
Authors: Kojima Takahiko 
Published: February 2020

Supramolecular assemblies based on intermolecular hydrogen bonding (H bonding) have been intensively investigated to develop functional materials. Along this line, we have developed supramolecular assemblies using protonated and saddle-distorted porphyrins as H-bonding electron acceptors to gain unique photofunctionality of the assemblies.1 In order to expand the possibility of structures and components of the assemblies, it is required to develop a strategy to construct H-bonded supramolecular assemblies involving different components. Herein, we present selective formation of unusual H-bonded hetero-triads.
We examined formation of hydrogen-bonded supramolecular assemblies using dodecaphenylporphyrin (H­2DPP) with various acids including carboxylic acids, sulfonic acids, and carboxylic acids with positively charged moieties. It was revealed that the stability of homo-assembly (H4DPPX2; X = conjugate base of an acid) can be controlled by the strength of the H bonding depending on the acidity of an acid used to protonate H2DPP and the electrostatic repulsion between the H4DPP2+ cation and the positively charged moiety of an acid used.2 By employing a carboxylic acid with a pyridinium moiety, the PF6
- salt of N-benzyl-4-carboxyphenylpyridinium (BnPy+-COOH•PF6
-) to react with H4DPPCl2 in chloroform, we succeeded in the formation and crystal structure determination of a supramolecular hetero-triad, [H4DPP2+(Cl–)(BnPy+-PhCOO–)](PF6
–).

S. Fukuzumi, T. Honda, T. Kojima, Coord. Chem. Rev.
2012, 256, 2488-2502.

W. Suzuki, H. Kotani, T. Ishizuka, Y. Shiota, K. Yoshizawa, T. Kojima, Chem. Commun.
2017, 53, 6359.
Supramolecular Chemistry of Cobalt-Corrins
Authors: Kräutler Bernhard 
Published: February 2020

Cobalt corrins are chiral relatives of the cobalt porphyrins, in which the ligand is much less unsaturated and is also ‘contracted’ by one carbon. This type of ligand strongly affects the redox and coordination chemistry of the bound cobalt center. Some lipophilic artificial cobalt corrins have been prepared in tremendous synthetic efforts in the Eschenmoser labs. The natural analogues offer an apparently more straight forward chemical entry to cobalt corrins. However, the natural cobalt corrins are all hydrophilic and highly substituted at their periphery, and they are distantly related to heme and chlorophyll. Although these cobalt corrins are very soluble in water, their natural roles are intimately connected with their essential and rich organometallic chemistry, which is all cobalt-centered.[1]

In this lecture, means for specific supramolecular assemblies based on modified natural cobalt corrins are delineated, as well as consequences of the supramolecular restructuring on the organometallic and redox-chemistry. So far, in the excursions to be reported, the cobalt corrin core is not altered and its redox and spectral properties are largely conserved.
A unique basis for specific supramolecular assemblies is then provided by the (organometallic) ligand itself, either, when attached to and bridging more than one metal center, or, when providing a structuring interface itself, for the build-up of supra-molecules. In a second general type of supramolecular assemblies the functional groups attached at the peripheral substituents of the natural corrinoids are used in a uniform way. By this means, the direct environment of the cobalt corrin moiety may be affected and structured in a global fashion, generating, e.g., a type of molecular micelles. A third type of supramolecular assembly makes selective use of single sites of the complex, but largely conserved sphere of the peripheral substituents, in order to generate specifically structured cobalt-corrins and their dimers. These latter ones may feature binuclear (organometallic) coordination chemistry, which would allow for synchronized redox processes in a highly structured, ‘second’ sphere around the metal centers.
I thank the Austrian Science Foundation (FWF, project P-28892 and earlier projects) for generous financial support.
References
[1] B. Kräutler, B. Puffer, in Handbook of Porphyrin Science, Vol. 25 (Ed.: K. M. Kadish, Smith, K. M., Guilard, R.), World Scientific, 2012, pp. 133-265.
Porphyrin-Hexabenzocoronene Systems
Authors: Jux Norbert , Lungerich Dominik , Hölzel Helen , Ruppel Michael , Martin Max 
Published: February 2020

We will present new architectures based on porphyrins and hexaarylbenzenes/hexabenzocoronenes. Special emphasis lies on crystal packing phenomena.
We report on the synthesis, characterization, and properties of some of these novel systems.[1-3]

References

[1] J. M. Englert, J. Malig, V. A. Zamolo, A. Hirsch, N. Jux, Chem. Commun. 2013, 49, 4827 – 4829.
[2] D. Lungerich, J. F. Hitzenberger, M. Marcia, F. Hampel, T. Drewello, N. Jux, Angew. Chem. Int. Ed..
2014,
53, 12231-12235.
[3] D. Lungerich, J. F. Hitzenberger, W. Donaubauer, T. Drewello, N. Jux, Chem. Eur. J.
2016, 22, 16755-16759.

Figure 1
Environmentally Friendly Coatings for Improved Stainless Steel Corrosion Resistance from Biorefinery Side Streams
Authors: Dastpak Arman , Yliniemi Kirsi , Monteiro Mariana , Höhn Sarah , Lundström Mari , Virtanen Sannakaisa , Wilson Benjamin Paul 
Published: February 2020

Although metals are routinely used in medical implant applications, corrosion of these inserted materials is an issue that can potentially have significant health impacts. For example, Stainless steel (SS) 316L - one of the most commonly used implant substrates - undergoes corrosion under physiological conditions. Such material degradation leads to the release of various potentially carcinogenic ions (e.g. Fe, Cr, Ni1,2) and over 90% of SS 316L implant failures are estimated to as a result of corrosion2. Fortunately, many of these difficulties can be mitigated through the use of biocompatible coatings on implant surfaces.
In this research, the effect of a lignin-based coating on SS 316L corrosion resistance was investigated. Two distinct types of lignin (from Soft and Hardwood) were dissolved in solvent and spin-coated on SS 316L. Subsequent surface characteristics were analysed by different techniques (AFM, FTIR) and the corrosion resistance of the obtained surfaces were studied by electrochemical methods. Results show that the presence of a lignin coating leads to an increase in surface wettability, whilst decreasing the measured corrosion current density of the metal by 2-3 orders of magnitude.
Overall, this research clearly highlights the potential of lignin from Biorefinery side streams as a sustainable and environmentally friendly coating for corrosion protection.

Keywords: Lignin, organic coatings, spin coating, SS316L corrosion
The authors acknowledge the Technology Industries of Finland Centennial/Jane and Aatos Erkko Foundations “Future Makers: Biorefinery Side Stream Materials for Advanced Biopolymer Materials (BioPolyMet)” project for funding this research. In addition, this work made use of facilities provided by the RawMatTERS Finland Infrastructure (RAMI) at Aalto University, which is supported by Academy of Finland.

References

Shih C, et al. Growth inhibition of cultured smooth muscle cells by corrosion products of 316L stainless steel wire. J Biomed Mater Res. 2001;57(2):200-207

Douglas CH. Metal corrosion in human body: The ultimate bio-corrosion scenario. The Electrochemical Society INTERFACE. Summer 2008;17(2):31
Enhanced Corrosion Mitigation of TiO2 coated Stainless Steels Under UV Illumination
Authors: Sathasivam Kamalasekaran , Yeh Tsung-Kuang , Wang Mei-Ya 
Published: February 2020

Austenitic stainless steels are commonly used as the structural material for dry-storage canisters in nuclear power plants because of their excellent corrosion resistance and mechanical properties. Dry-storage canisters are often exposed to chloride containing atmosphere near seashores, which could induce localised stress corrosion cracking in these stainless steels near the welded regions. TiO2 coatings applied on stainless steel substrates (i.e. Type 304 stainless steels) along with ultraviolet (UV) irradiation have been proposed as a mitigation measures against the corrosion in canister materials.
In this study, TiO2 coatings were applied on stainless steel samples using a sol-gel dip-coating method. The corrosion characteristics of the coated samples were studied under the conditions of different coating treatments, annealing temperatures, annealing atmospheres and UV illumination durations. The corrosion mitigation performance of the coated samples with and without UV illumination was evaluated by electrochemical polarization analyses and open-circuit potential measurements. The surface morphologies of the samples were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and laser Raman spectroscopy. In addition, the photocatalytic responses of these coatings exposed to various acidic and alkaline aqueous solutions under aerated and deaerated conditions were also studied. The results indicated that the TiO2 coating not only could lead to low electrochemical potentials of the stainless steel samples during UV illumination, but could also maintain the low electrochemical potentials even after the cut off of UV illumination. Results from Electrochemical polarization analyses further support the superior corrosion resistance under UV-illumination conditions.
Keywords: Stainless steel, TiO2 coating, ultraviolet illumination.
Microstructural and Electrochemical Characterization of Friction Stir Welded Aluminum Alloys
Authors: Magnani Marina , Gonçalves Haroldo Marques , Benedetti Assis Vicente , Fugivara Cecilio Sadao 
Published: February 2020

Aluminum alloys of 2000 and 7000 series containing cooper and zinc, respectively, as the main alloying element are extensively used in aircraft structures. However, these classes of aluminum alloys are difficult to join by conventional fusion welding techniques because the dendritic structure formed in the fusion zone can seriously compromise the mechanical and corrosion resistance properties of the joint. Friction Stir Welding (FSW) is attractive for joining high strength aluminum alloys since there is far lower heat input during the process compared with conventional welding methods. FSW is produced by rotating and plunging a specially-designed cylindrical, shouldered tool with a small diameter pin into the joint line between two butted plates. Frictional heat causes the metal to soften and allows the tool to traverse along the joint line [1]. The FSW process generates three distinct microstructural zones: the nugget, the thermomechanically affected zone (TMAZ) and the heat-affected zone (HAZ). These microstructural modifications generally interfere in the performance of the corrosion resistance of welded alloys. In the present study, FSW was used to join two dissimilar aluminum alloys, AA2024-T3 (Al-Cu-Mg) and AA7475-T651 (Al-Cu-Mg-Zn) and the effect of this process on the corrosion resistance of the welded joints and on the microstructure of the alloys was evaluated. Microstructural characterization was carried out by optical microscopy, scanning electron microscopy and atomic force microscopy. The weld zone regions showed significant microstructural changes. Electrochemical impedance spectroscopy (EIS) and Electrochemical noise measurements (ENM) were used to evaluate the corrosion resistance of the different zones of the weld in NaCl solution. Local electrochemical measurements using an electrochemical microcell were carried out across the transverse cross section of the welds. The cell containing the solution, counter and reference electrodes is attached to the carousel of an optical microscope. The electrochemical results showed that the corrosion behavior of the AA2024-T3 / AA7475-T651 alloy is dominated by the electrochemical activity within the intermetallics (IMs). The weld zone regions containing copper IMs have a more noble character than the regions containing Zn and Mg IMs. Therefore, the results showed an increased susceptibility of welded joints to these forms of corrosion in comparison to the unaffected base metal by a more severe attack related to AA7475-T651 alloy.
Reference
[1] M. Jariyaboon et al. Corrosion Science 49 (2007) 877–909.
[2] J.-Q. Su et al. Acta Materialia 51 (2003) 713–729
Acknowledgement: Fapesp 2013/132356
Thermal Oxidation-Induced Self-Healing on Yttrium Silicate Composites Dispersed with Silicon Carbides
Authors: Nanko Makoto , Dinh Vu Huy 
Published: February 2020

SiC/SiC composites are expected as new generation of gas turbine materials. However, SiC is remarkably oxidized in the combustion gas atmosphere due to existence of water vapor to lead to evaporation of SiO2 scale. In order to protect SiC/SiC composites from water vapor in the combustion gas, environmental barrier coatings (EBCs) system was proposed. Protective coating from water vapor in the EBCs system consists of oxide materials such as mullite, LaBaSiO2, Y2SiO5/Y2Si2O7, and Yb2SiO5/Yb2Si2O7. However, EBCs system loses productiveness for water vapor when EBCs were cracked penetrating into the substrate SiC/SiC composites.
Nowadays, many self-healing ceramics have been developed such as SiC/Al2O3, SiC/mullite and Ni/Al2O3. In these ceramics, non-oxide dispersoids are oxidized on the crack surface to fill the crack with the oxidation product. In any cases, the oxidation product is formed to fill the crack via diffusion of cations through the matrix oxide.
In this report, self-healing EBCs system is proposed with Y2SiO5 and Y2Si2O7 composites dispersed with SiC particles. Self-healing effectiveness of the composites was evaluated with crack-disappearance by high-temperature oxidation in air. In order to fit the CTE of EBCs system to that of SiC/SiC composites, mixture of Y2SiO5 and Y2Si2O7 was used. SiC/(Y2SiO5+Y2Si2O7) composite is also investigated on its self-healing effectiveness on the surface cracks.
Y2SiO5 and Y2Si2O7 were prepared by reaction of powder mixture of Y2O3 and SiO2 at 1400°C in air. Powder mixture of yttrium silicates with 5 vol% of SiC powder was consolidated by using the pulsed electric current sintering at 1500°C for 5 min under 70 MPa in vacuum. In the mixture matrix composites, mixture of 30 vol% Y2SiO5 and 70 vol% Y2Si2O7 was prepared. Surface cracks (200 mm in surface length) was introduced into polished surface of the composite samples with the Vickers indentation. Figure 1 shows the surface cracks of (a) SiC/Y2SiO5, (b) SiC/Y2Si2O7 and (c) SiC/(Y2SiO5+Y2Si2O7). Thermal oxidation experiments were conducted in air at temperature of 1300°C for 1 and 6 h. Crack-disappearance after thermal oxidation was evaluated by crack length before/after thermal oxidation.
Figure 2 shows surface appearance of (a) SiC/Y2SiO5 and (b) SiC/Y2Si2O7 for 1 h. Surface cracks are filled by the oxidation product Surface cracks was completely disappeared by thermal oxidation for both of SiC/Y2SiO5 and SiC/Y2Si2O7 at 1300°C for 1 h. Figure 3 shows surface appearance of SiC/(Y2SiO5+Y2Si2O7) at 1300°C for 1 h. Surface cracks of SiC/(Y2SiO5+Y2Si2O7) was completely disappeared. Self-healing effectiveness of SiC/(Y2SiO5+Y2Si2O7) is similar with the monolithic matrix composites.
The authors wish to express their gratitude to the Japan Science and Technology Agency for supporting partially this study through the Advanced Low Carbon Technology Research and Development Program.

Figure 1