bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Electronic and Photophysical Properties of Surface-Anchored Metal-Organic Frameworks (SURMOFs)
Authors: Wöll Christof 
Published: February 2020

The huge versatility and unparalleled level of control in the design of metal-organic frameworks (MOFs) has recently been shown to also carry a huge potential for applications based on the electrical, electronic and photophysical properties of this rich class of materials. Recent examples are MOF-based electrochemical [1,2], photo-electrochemical [3] and photovoltaic devices [4,5], as well as photon-upconversion [6]. Since at present methods to provide reliable and reproducible contacts to MOF-materials are scarce, we have developed a method to produce well-defined, highly oriented and monolithic MOF thin films supported on different types of surfaces, also referred to as SURMOFs [7]. This procedure in particular allows the fabrication of hetero-multilayers (see Fig. 1). In this talk, we will describe the fabrication of such well-defined model systems 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. In this talk, we will demonstrate that the huge size of the chemical space spanned by MOFs can be further drastically increased by loading MOFs with nanoparticles or quantum dots. In this context, SURMOFs offer particular advantages since the loading can be carried out in a layer-by-layer fashion, offering the potential to fabricate hetero-mulitlayers.
References:
[1] A. Dragässer, O. Shekhah, O. Zybaylo, C. Shen, M. Buck, Ch. Wöll, D. Schlettwein, Chem. Comm., 48, 663 (2012)
[2] J. Liu, M. Paradinas, L. Heinke, M. Buck, C. Ocal, V. Mugnaini, Ch. Wöll, Chem.Elektro.Chem., 3, 713 (2016)
[3] Lu Ye, J. Liu, Y. Gao, Ch. Gong, M. Addicoat, Th. Heine, Ch. Wöll, L. Sun, J. Mater. Chem. A, 4, 15320, (2016)
[4] 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)
[5] 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)
[6] 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)
[7] Jin-L. Zhuang, A. Terfort, C. Wöll, Coordination Chemistry Reviews, 307, 391, (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)

Figure 1
(Invited) Synthesis of Ordered Semiconductor Nanostructures for Energy Conversion Using Anodic Porous Alumina
Authors: Masuda Hideki , Kondo Toshiaki , Yanagishita Takashi 
Published: February 2020

Efficient synthesis of the ordered nanostructures of semiconductors is important issue to be solved for the preparation of the photo-energy conversion systems with high efficiency [1]. For the effective preparation of the ordered nanostructures of semiconductors, the use of the naturally occurring ordered nanomaterials is promising for the synthesis due to its capability of the preparation of ordered nanostructures with high efficiency. Among them, anodic porous alumina, which is formed by anodization of Al in acidic electrolyte, is one of promising material due to ist precisely controllable geometrical nanostructures [2]. In the present report, the synthesis of the ordered nanostructures of semiconductors using anodic porous alumina templates will be described. The template synthesis using highly ordered anodic porous alumina allows the preparation of ordered nanostructures of the semiconductors. In addition, the application of the highly ordered anodic porous alumina with reduced hole intervals (~25 nm) and hole sizes (~10 nm) prepared under the low voltage anodization [3] generated the ordered structures of semiconductors with small dimensions. In the experiment, semiconductor (ZnO [4,5], CdS) nanorod arrays were prepared by electrochemical or hydrothermal synthesis of semiconductors using anodic porous alumina templates. The geometrical structure of the obtained nanorod arrays of semiconductors could be precisely controlled based on the ordered structures of anodic porous alumna. The synthesis of the nanorod arrays on the conducting substrates (ITO etc.) could provide the current collection electrodes with large surface area. The present process will be used for the preparation of nanostructures of semiconductors, which are required for the preparation of various kinds of photoenergy conversion systems with high efficiency, such as organic photovoltaic solar cells [6].
1. T. Shinagawa, S. Watase, M. Izaki, Cryst. Growth Des., 11, 5533 (2011).
2. H. Masuda and K. Fukuda, Science, 268, 1466 (1995).
3. H. Masuda, K. Takenaka, T. Ishii, K. Nishio, Jpn. J. Appl. Phys., 45, L1165 (2006).
4. M. Izaki, T. Omi, Appl. Phys. Lett., 98, 2439 (1996).
5. T. Özdal, R. Taktakoğlu, H. Özdamar, M. Esen, D. K. Takҫi, H. Kavak, Thin Solid Films, 592, 143 (2015).
6. B. Kippelen, J.-L. Brédas, Energy Environ. Sci., 2, 251 (2009).
(Invited) Organic-Inorganic Hybrid Solar Cells with Antimony Sulfide-Metal Composites
Authors: Yukawa Mayumi , Hayakawa Akinobu , Sagawa Takashi 
Published: February 2020

Since antimony sulfide (Sb2S3) has much attraction for photovoltaics in terms of appropriate bandgap, high absorption coefficient, low toxicity, and abundance, it has been recently applied for organic-inorganic hybrid solar cells, which has been attained the power conversion efficiency (PCE) of 7.5%.[1] We also have prepared Sb2S3-based solar cells with TiO2 or ZnO nanoparticles for electron transporting layer in addition to poly(3-hexylthiophene)-2,5-diyl (P3HT)/ (3, 4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS), zinc phthalocyanine (ZnPc), or MoO3 for hole transporting layer and compared their photovoltaic performance. Among these hybrid solar cells, it was found that the combination with ZnPc and TiO2 has the highest durability with keeping the relative PCE of 90% after the stability test under 1 sun at 63 °C at a relative humidity of 50% for 1,500 h.[2] For further improvement of the photovoltaic performance, we newly added La or Zn into　the precursor of Sb2S3 to prepare Sb2S3–metal composites and applied them for organic-inorganic hybrid solar cells.
Remarkable enhancement of the open-circuit voltage for glass-FTO/TiO2/Sb2S3 + La/P3HT/poly[(3-carboxybutyl)thiophene-2,5-diyl] (P3CT)/Au was observed after the addition of La to Sb2S3 and 33% improvement of PCE was attained. Impedance analyses of the hybrid solar cells with or without La revealed that the resistance at the interface was effectively lowered through the addition of La though the bulk-resistance had not been changed. It was found that the added La was phase-separated and accumulated between the layers of TiO2 and SbS3 through the TEM-EDX observations of the cross-sectional views of the La-added device. In this context, La was not doped into Sb2S3 but inserted into the interface of TiO2 and SbS3.
On the contrary, addition of Zn into the Sb2S3 precursor resulted in the enlargement of the crystalline size of the Sb2S3 from 14 nm to 25 nm, which was estimated from XRD peaks. No phase-separation was confirmed by TEM observations of the cross-sectional views. Therefore, it was concluded that the Zn was doped into Sb2S3. By using the Zn-doped Sb2S3, remarkable increment of the current density was observed in addition to relatively high fill factor and 57% improvement of PCE. These results are ascribed to the effective lowering the bulk-resistance, which was confirmed by the impedance analyses.
[1] J. A. Chang, J. H. Rhee, S. H. Im, Y. H. Lee, H. J. Kim, S. I. Seok, M. K. Nazeeruddin, and M. Graetzel, Nano Lett., 2010, 10, 2609–2612.
[2] A. Hayakawa, M. Yukawa, and T. Sagawa, ECS Trans., ahead of print.
(Invited) Photoinduced Charge Transfer Reactions in Chiral, Semiconducting Polymer-Wrapped Single-Walled Carbon Nanotube Superstructures
Authors: Bai Yusong , Bullard George , Olivier Jean-Hubert , Park Jaehong , Glesner Mary G. , Therien Michael J. 
Published: February 2020

Highly charged, chiral anionic semiconducting polymers helically wrap single-walled carbon nanontubes (SWNTs) at periodic and constant morphology. These polymers can be used as tools to modulate SWNT electronic properties, provide expansive solubility, or engineer electron acceptor units at rigorously defined intervals along the nanotube backbone. We detail (SWNT)-based nanohybrid compositions based on (6,5) chirality-enriched SWNTs ([(6,5) SWNTs]) and chiral n-type polymers such as (S-PBN(b)-Ph4PDI), that feature a perylenediimide (PDI)-containing repeat unit; S-PBN(b)-Ph4PDI-[(6,5) SWNT] superstructures, for example, feature a PDI electron acceptor unit positioned at 3 nm intervals along the nanotube surface, thus controlling rigorously SWNT–electron acceptor stoichiometry and organization. Potentiometric studies determine driving forces for photoinduced charge separation (CS) and thermal charge recombination (CR) reactions, as well as spectroscopic signatures of SWNT hole polaron and PDI radical anion states. Femtosecond pump-probe transient absorption spectroscopic experiments show that excitation into the SWNT E11 transition of a S-PBN(b)-Ph4PDI-[(6,5) SWNT] superstructure generates SWNT hole polaron [(6,5) SWNT(•+)n] and PDI radical anion (PDI−•) states. Here we describe related compositions that detail reaction driving force- and solvent-dependent photoinduced CS and thermal CR reactions, and provide insights into the factors that govern photoinduced charge transfer reactions at soft matter-hard matter interfaces defined by polymers and SWNTs.

Figure 1
(Invited) De-Coupled Electron and Heat Transfer: A Possible Nature’s Strategy for Maximizing Electrocatalysis for CO2 Fixation
Authors: Nakamura Ryuhei 
Published: February 2020

How has nature handled electron flow for carbon fixation? We know the mechanism of carbon fixation taking place inside chloroplast. At least, we know the framework of its action and function. Parallelly important, yet relatively unknown processes are carbon fixation taking place in deep-sea hydrothermal environments, which contain low levels or no solar radiation. In such environments, nature has to develop the systems to harvest geochemical and geothermal energy to generate high-energy electrons needed for carbon fixation. Yet, how nature utilizes temperature and chemical gradient fostered by geological settings remains largely unknown. In this talk, based on our findings of electrical current generation across a black smoker hydrothermal vent,[1,2] together with thermoelectrical conversion by deep-sea minerals,[3] I provide the new energetic underpinning of carbon fixation: de-coupled electron and heat transfer at deep-sea hydrothermal vents [4,5]. As catalysis at the deep-sea vent may tightly link with the origin and evolution of life, I provide the perspective to predict the first engine that drives the life emergence and fosters life complexity.
(1) R. Nakamura, et al. Angew. Chem. Int. Ed., 49, 7692 (2010). (2) M. Yamamoto, et al. Angew. Chem. Int. Ed., 52, 10758 (2013). (3) R. Ang, et al. Angew. Chem. Int. Ed., 54, 12909 (2015). (4) A. Yamaguchi, et al. Electrochim. Acta, 141, 311 (2014). (5) A. Yamaguchi, et al. Springer, Chapter 4.3.2. (2016).
(Invited) Formation of One-Dimensional Au-Directed Organometallic Nanostructures with Large Acene Precursor Molecules
Authors: Hayashi Hironobu , Urgel José Ignacio , Deniz Okan , Giovannantonio Marco Di , Dienel Thomas , Ruffieux Pascal , Fasel Roman , Yamada Hiroko 
Published: February 2020

Large aromatic molecules such as large acenes and polycyclic aromatic hydrocarbons are regarded as promising materials for organic electronic devices. However, it is normally difficult to synthesize such large aromatic molecules because of the low solubility and stability. On the other hands, we have developed thermal and photochemical precursor methods to overcome these problems. Bicyclo[2.2.2]octadiene(BCOD)-fused acenes can be converted to the corresponding acenes by the thermally induced retro-Diels-Alder reaction, while α-diketone-type precursors can be converted simply by photoirradiation. Specifically, irradiation of a-diketone-type precursors at the n-π* absorption leads to the release of two molecules of CO, and the corresponding acenes can be prepared quantitatively in solutions or in films. Importantly, these precursor molecules are often more soluble and stable than the corresponding one.
Here we report the synthesis of thermally convertible pentacene and photochemically convertible heptacene precursor molecules. Namely, BCOD moieties were introduced in a pentacene aromatic core as thermally removable leaving groups, while α-diketone moieties were introduced in a heptacene aromatic core as photochemically removable leaving groups. In addition, we also report a combined scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM) study to observe the conversion of precursor molecules into the corresponding acenes on a pristine Au(111) substrate under ultrahigh vacuum (UHV) conditions. For example, the STM and nc-AFM images clearly displays that the annealing of pentacene precursor molecule deposited Au(111) substrates at 390 K result in the one-dimensional (1D) Au-directed organometallic nanostructures. Further annealing at 475 K produced the 1D pentacene organometallic nanostructures.
Our result indicates that the precursor method and on-surface synthesis would be a good combination for making novel structure.
Synthesis of Bent and Distorted Expanded Porphyrins
Authors: Kuzuhara Daiki , Xue Songlin , Furukawa Wataru , Aratani Naoki , Yoshimoto Noriyuki , Yamada Hiroko 
Published: February 2020

Expanded porphyrins have been widely studied in their specific characteristics of NIR absorption and emission, non-linear optics, versatile electronic states, and multinuclear metal complexes. Generally, porphyrin and related compounds consist of one meso-carbon between pyrrole units, which usually provide the planar and rigid structures. On the other hand, an increase of the numbers of meso-carbons and pyrroles forms flexible frameworks in the formation of bent and distorted structures. Recently, we succeeded to synthesize aromatic rings–fused porphyrin(2.1.2.1) from dipyrrolylbenzene (DPB) [1] and a series of porphyrin(2.1.2.1), hexaphyrin(2.1.2.1.2.1) and octaphyrin(2.1.2.1.2.1) from diphenyldipyrrolylethene (DPDPYE). These porphyrins have unique bent and distorted structures, which are revealed by X-ray crystallography. Porphyrin(2.1.2.1) and hexaphyrin(2.1.2.1.2.1) work as nuclear ligands, which are able to be converted to various metal complexes. The electronic, optical and electrochemical properties and single crystal structures of these expanded porphyrins will be discussed.
Reference
[1] Kuzuhara, D.; Furukawa, W.; Kitashiro, A.; Aratani, N.; Yamada, H. Chem. Eur. J.
2016, 22, 10671.
Facile Synthesis of Cofacial Porphyrin Oligomers Via the Catalyst-Free Aromatic Nucleophilic Substitution Reactions
Authors: Yamashita Ken-ichi 
Published: February 2020

Cofacial porphyrin dimers have attracted a considerable attention due to their potential as artificial reaction centers in the photosystem, bimetallic catalysts and function as host molecule. However, their syntheses have required troublesome multi-step reactions. Recently, we have reported a facile and efficient synthetic method for meso-heteroatom-substituted porphyrins from the corresponding meso-bromoporphyrins via the catalyst-free aromatic nucleophilic substitution (SNAr) reactions.1,2,3 In this work, we applied this efficient method to the synthesis of cofacial porphyrin dimers bridged by the dihydroxyarene derivatives. Reaction of resorcinol with an excess of meso-bromoporphyrin in the presence of base afforded the acyclic dimers 1 in good yield. The steric hindrance between porphyrin and substituents on resorcinol determined their formations. For example, 4,6-diethylresorcinol gave cofacial conformation whereas 2-methylresorcinol gave open conformation. Reaction of resorcinol or 2,7-dihydroxynaththalene with meso-dibromoporphyrin afforded cyclic porphyrin dimers 2 and 3 with rigid cofacial conformation in good yield. We will also report the synthesis, structural characterization, and physical properties of the obtained dimer and their metal complexes.

References

(1) K. Yamashita, K. Kataoka, M. S. Asano, K. Sugiura, Org. Lett.
2012, 14, 190–193.
(2) K. Yamashita, S. Sakamoto, A. Suzuki, K. Sugiura, Chem. Asian J.
2016, 11, 1004–1007.
(3) K. Yamashita, K. Kataoka, S. Takeuchi, M. S. Asano, K. Sugiura, J. Org. Chem.
2016, 81, 11176–11184.

Figure 1
Redox Properties of Transition-Metal/Organic Chromophore Arrays: Interplay Between Metal- and Chromophore-Centered Electron-Transfer Processes
Authors: Nemykin Victor V. , Zatsikha Yuriy V. , Kovtun Yuriy P. , Ziegler Christopher J. 
Published: February 2020

A large number of ferrocene-containing BODIPYs, azaBODIPYs, and BOPHYs along with several examples of non-innocent transition-metal aza-dipyrromethenes have been prepared and characterized by UV-Vis-NIR, NMR, HRMS, and X-ray crystallography. The redox properties of all target compounds were investigated by electrochemical and spectroelectrochemical methods. The experimental electronic, spectroscopic, and geometric parameters of the organometallic BODIPYs, azaBODIPYs, and BOPHYs as well as transition-metal aza-dipyrromethenes were correlated with DFT and TDDFT calculations.
Electrochemistry of Porphyrazines with Exocyclic Pended Pyridyl and N-Methylpyridyl Rings
Authors: Kadish Karl M , Cong Lei , Sciscione Fabiola , Viola Elisa , Donzello Maria Pia , Ercolani Claudio 
Published: February 2020

Two new series of porphyrazines with exocyclic pended 2-pyridyl and 2-N-methylpyridyl rings were investigated as to their electrochemical properties. The structures of the investigated compounds are shown in Chart 1a and represented in one case as [Py8PzM], where M = 2H, MgII(H2O), CoII, CuII or ZnII and in the other as [(2-Mepy)8PzM]8+, where M = MgII(H2O) or ZnII. The redox behavior of these new compounds is then compared to that of earlier synthesized porphyrazines with p-extended systems which are represented as [Py8PyzPzM] (Chart 1b), and [Py8QxPzM] where Qx = quinoxaline. Each porphyrazine undergoes multiple one-electron reductions in DMSO, benzonitrile, pyridine or CH2Cl2 while the two octacationic porphyrazines, [(2-Mepy)8PzM]8+, also exhibit 2 or 3 one electron reductions in water containing 0.1 M NaOAc or 0.1 M KCl as supporting electrolyte. The potentials for each redox reaction were measured by cyclic voltammetry and thin-layer UV-visible spectroelectrochemistry was used to characterize some of the redox reactions. Special emphasis was placed on the cobalt(II) derivative [Py8PzCoII]+, which is oxdized in a single step to give [Py8PzCoIII] or reduced in up to five one-electron transfer steps, with the exact potentials and site of electron transfer depending upon the solvent. Pyridine was shown to strongly coordinate to the metal center of [Py8PzCoII] and [Py8PzCoIII] and binding constants were calculated using standard equations. Finally, comparisons are made between redox behavior of the three types of compounds in Chart 1, [Py8QxPzM] and the well-characterized phthalocyanines, [PcM], having the same central metal ions.

Chart 1. Structures for (a) newly investigated porphyrazines and (b) related porphyrazines with p-extended structures.(In the figure : 1) change formula: [(2-Mepy)8PzM]8+ instead of [(CH3-Py)8PzM] ; 2) change the order of metal centers and put the oxidation state: M = 2H, MgII(H2O), CoII, CuII, ZnII instead of M = Mg(H2O), Cu, Zn, 2H, Co ; 3) put M = MgII(H2O), ZnII instead of M = Mg(H2O), Zn)

Figure 1
Electrochemistry and Protonation of Open-Chain Pentapyrroles and Sapphyrins with Highly Electron-Withdrawing Meso-Substituents
Authors: Shan Wenqian , Naitana Mario L. , Desbois Nicolas , Blondeau-Patissier Virginie , Quesneau Valentin , Gros Claude , Huang Wenhao , Ou Zhongping , Kadish Karl M. 
Published: February 2020

A series of open-chain pentapyrroles and sapphyrins with highly electron-withdrawing meso-tetraaryl groups were synthesized and characterized as to their electrochemistry and protonation reactions in nonaqueous media. The chemical conversion of pentapyrroles to sapphyrins upon oxidation in acid media is known but it was not known if sapphyrins could be electrosynthesized from pentapyrroles under the appropriate solution conditions. This was investigated in the present study which compares the redox behavior and acid-base properties of pentapyrroles to that of sapphyrins having the same meso-substituents. The investigated compounds were each characterized by UV−vis and 1H NMR spectroscopy, mass spectrometry and electrochemistry, in addition to spectroelectrochemistry. Structures of the investigated compounds are shown in Chart 1 and are represented as (Ar)4PpyH3 and (Ar)4SapH3.
Cyclic voltammetry was used to measure redox potentials and spectroelectrochemistry was used to monitor the products of each redox reaction. The protonation processes were monitored by UV-vis absorption spectroscopy as protons were added to the investigated compounds in the form of trifluoroacetic acid (TFA). Equilibrium constants were calculated using both the Hill equation and the Mole Ratio method. The electrochemical data, the protonation constants and previous reported mechanisms for reduction and oxidation of pentapyrroles and sapphyrins with other meso-tetraaryl groups were then analyzed as a function of the solvent properties and para-substituents on the four phenyl rings of compounds in the two series.

Figure 1
Synthesis of Oligomeric Benzoporphyrins Via Imidation
Authors: Hu Yi , Jinadasa R. G. Waruna , Wang Hong 
Published: February 2020

In recent years, it is known that the porphyrin electronic system is susceptible to conjugative perturbation at the periphery. [1] So, the electronic and optical properties of porphyrin can be rationally tuned. Because of this, a variety of conjugated porphyrin arrays have been constructed over the last two decades. It is one strategy to link electron donors and electron acceptors together using π-conjugated molecular spacers to investigate photoinduced electron transfer processes on a molecular level. [2] The electronic properties of these molecules make them potentially useful in molecular photonics, optoelectronics, nanoscale application and in solar energy conversion. [1]

In this work, we report the synthesis and electronic properties of conjugated porphyrin dimer and monomers. All the porphyrins were synthesized using bromination, palladium catalyzed domino heck reaction followed by electrocyclization/dehydration strategy [3]and then imidation with coupling reagents.
Reference
[1] S. V. Kirner, D. Arteaga, C. Henkel, J. T. Margraf, N. Alegret, K. Ohkubo, B. Insuasty, A. Ortiz, N. Martı´n, L. Echegoyen, S. Fukuzumi, T. Clark and D. M. Guldi, Chem. Sci.,

2015, 6, 5994–6007
[2] S. Fukuzumi, K. Ohkubo and T. Suenobu, Acc. Chem. Res., 2014, 47, 1455.
[3] Jinadasa, R. G. W.; Fang, Y.; Kumar, S.; Osinski, A. J.; Jiang, X.; Ziegler, C. J.; Kadish, K. M.; Wang, H. J. Org. Chem., 2015, 80 (24), 12076–12087

Figure 1