bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polymer-Templated Carbon Hybridized Nanostructured Transition Metal Oxide As Advanced Lithium-Ion Anodes
Authors: Jiang Beibei , Li Bo , Lin Zhiqun 
Published: February 2020

An enormous spectrum of applications of lithium-ion batteries (LIBs), particularly in electric vehicles (EVs), hybrid EVs and electric grids, invokes essential requirements on their energy storage capabilities. However, the most common commercial graphite anode material still exhibits a relatively low theoretical specific capacity of 372 mAh g-1, which cannot meet the demand of the high-energy applications noted above. To date, a wide variety of anode materials with much higher capacities have been extensively investigated. In this regard, transition metal oxides (MxOy, where M is Fe, Co, Ni, Cu, Sn, Mn, etc.) clearly stand out as the promising alternatives to graphite owing to their attractive higher theoretical capacities (＞ 600 mAh g-1), low cost, environmental friendliness and wide availability containing earth-abundant elements. To further achieve high rate capability, hybrid nanomaterials with more conductive carbonaceous materials have been constructured. The ability to create a synergistic effect of nanostructure engineering and its hybridization with conductive carbonaceous material is highly desirable for attaining high-performance lithium ion batteries (LIBs). However, it remains challenging to achieve this synergy.
Here we propose a general method to create a synergistic effect of nanostructure engineering and its hybridization with conductive carbonaceous material. Star-like and bottlebrush-like poly (acrylic acid)-block-polystyrene (PAA-PS) diblock copolymer and polystyrene-block-poly(acrylic acid)-block-polystyrene (PS-PAA-PS) triblock copolymer with controlled dimensions will be synthesized through atom transfer rapid polymerization (ATRP). Through a strong coordination bonding between the metal moiety of inorganic precursors and the functional groups of PAA (-COOH), the inorganic precursors can be selectively incorporated into the space formed by the PAA block. As a result, nanostructured transition metal oxide solid nanocrystals and hollow nanocrystals can be synthesized guided by the PAA-PS and PS-PAA-PS templates, respectively. In addition, by changing the polymeric templates from star-like to bottlebrush-like structure, the transition metal oxide nanocrystals varied from isotropic (i.e. nanoparticles, hollow nanoparticles) to anisotropic (i.e. nanorods, nanotubes). The diameter of the transition metal oxide nanocrystals is determined by the dimension of the PAA part, and it could be easily changed by varying the molecular weight of PAA part in the polymeric templates. Morever, the polymeric template not only serves as an easy control over the size and shape of the inorganic nanocrystals, but also acts as carbon source when calcinated at high temperature at argon atmosphere. We demonstrated that the carbon-hybridized nanocrystals obtained by the polymer templating method would be superior anode materials for LIBs.
Hierarchically Nanostructured MoS2 Catalyst Synthesis for High Efficient Hygrogen Evolution Reaction Via Electrospinning
Authors: Lee Kyu Hwan , Choi Sung Mook , Hahm Myung Gwan , Cho Byungjin , Rheem Youngwoo , Myung Nosang Vincent 
Published: February 2020

Hydrogen is considered as an energy storage and carrier for future energy demand. The ideal resource of hydrogen is water, as it is abundant and contains no carbon. Sustainable hydrogen can be produced from water splitting using electricity from renewable energy sources. Water splitting requires the HER, which needs the catalytic activity. While platinum and other precious metals are the best catalyst for the HER, replacing rare and expensive catalysts with earth-abundant materials would represent a significant step toward making hydrogen as an alternative energy source and facilitate the transition to a hydrogen economy. Hence, new efficient materials for renewable hydrogen production are greatly needed.
In this presentation, we will present that cost-effective way to synthesize hierarchically nanostructured MoS2 nanofibers and demonstrate them ability to produce hydrogen by water splitting. We fabricated and optimized a perpendicularly grown nanosheets on nanofiber core with high exposure of catalytic active edge sites and good electrical contact with core nanofibers using electrospinning process, which can produce the nanomaterials on industrial scale.
(Invited) Supramolecular-Driven Formation of an Elusive Phthalocyanine-C60 Fullerene Bisadduct Triad
Authors: Torres Tomas , Bottari Giovanni , Trukhina Olga , Guldi Dirk M. , Kahnt Axel , Mateo Luis-Manuel , Lavarda Giulia 
Published: February 2020

Phthalocyanines (Pcs) are planar, two-dimensional aromatic macrocycles which possess outstanding electrical and optical properties that make them perfect building blocks for their incorporation into multifunctional materials. Similarly, the excellent electron-accepting property of C60 fullerene renders this carbon nanostructure an ideal molecular partner for photo- and electroactive molecular systems such as Pcs.
Although several reports have appeared on the preparation of Pc-based, mono-functionalized fullerenes, not many examples have been reported concerning the double functionalization of C60 fullerene by Pcs, which remains problematic due to the formation of a large number of regio- and/or stereoisomers.
Here, we report a novel example of controlled bisaddition over C60 fullerene in which the occurrence of π-π supramolecular interactions between structurally-rigid, Pcs addends in solution led to the formation of a Pc2-C60 bisadduct triad in a regio- and stereocontrolled fashion. In the Pc2-C60 triad, the two Pc units are interacting through intramolecular π-stacking interactions, as demonstrated by several techniques (i.e., DABCO titration experiments, ground- and excited state photophysical studies, HPLC analysis, electrochemical studies, etc.).
(Invited) The Regioselectivity of Bingel-Hirsch Cycloadditions on IPR Endohedral Metallofullerenes
Authors: Garcia-Borràs Marc , Osuna Sílvia , Luis Josep M , Echegoyen Luis , Solà Miquel 
Published: February 2020

Given the large number of possible non-equivalent bonds of Endohedral MetalloFullerenes (EMFs), the elucidation of the preferred addition sites for a target reaction is tremendously challenging.1 The development of a set of simple rules able to rationalize the preferred regioselectivities by solely inspecting the fullerene structure would be extremely appealing for the whole fullerene community. This communication describes a set of predictive criteria called Predictive Aromaticity Criteria (PAC), to a priori identify the most reactive bonds of a given EMF towards the Bingel-Hirsch (BH) cycloaddition based on a simple evaluation of the cage structure, and without need to perform any expensive theoretical calculation or experimental measure.2

We take as starting point the investigation of the BH addition of diethylbromomalonate on all non-equivalent bonds of Sc3N@D3h-C78 using density functional theory calculations. From the Sc3N@D3h-C78 analysis, a set of rules that we called Predictive Aromaticity Criteria (PAC) is derived, which are further applied to predict the most favorable BH adducts for the challenging case of Sc3N@D5h-C80. The predictions based on PAC are afterwards fully confirmed by both the computational and experimental results of the complete study of the regioselectivity of BH reaction to Sc3N@D5h-C80. These results provide conclusive evidence on the reliability of the PAC, indicating that these rules are general and applicable to any BH reaction on IPR EMFs. Moreover, this work provides clear evidence of the key role played by the local aromaticity of the cage in EMF functionalization.2-5

References:

[1] M. Garcia-Borràs, S. Osuna, M. Swart, J.M. Luis and M. Solà, Chem. Soc. Rev.,
2014, 43 (14), 5089
[2] M. Garcia-Borràs, M. R. Cerón, S. Osuna, M. Izquierdo, J.M. Luis, L. Echegoyen, M. Solà, submitted for publication, 2015.
[3] M. Garcia-Borràs, S. Osuna, M. Swart, J.M. Luis and M. Solà, Chem. Commun., 2013, 49 (12), 1220
[4] M. Garcia-Borràs, S. Osuna, M. Swart, J.M. Luis, L. Echegoyen, Miquel Solà, Chem. Commun.,
2013, 49 (78), 8767
[5] M. Garcia-Borràs, S. Osuna, M. Swart, J.M. Luis and M. Solà, Angew. Chem. Int. Ed., 2013, 52 (35), 9275

Figure 1
(Invited) Distorted Aromatics and Their Related 1D and 2D Materials
Authors: Mateo-Alonso Aurelio 
Published: February 2020

Polycyclic aromatic hydrocarbons (PAHs) are receiving a great deal of attention because of their increasingly better performance in organic electronic applications. Among these, PAHs containing N atoms (N-PAHs) are particularly interesting since their electronic structure, stability, solubility, and supramolecular organization can be modulated by varying the number and position of N atoms.
In general, PAHs are planar structures but they can adopt twisted conformations as the result of the steric strain induced by overcrowding or congestion in key positions of the aromatic core. twisted-PAHs have shown enhanced solubility and unique optoelectronic and chiroptical properties as an effect of their distorted molecular structure.
We have developed a general strategy that provides access to a new family of twisted-N-PAHs (0D) with different twist angles by introducing silyl groups with different size and rigidity, providing direct experimental correlation between twist size and properties. In addition, this methodology has been successfully implemented in the preparation of 1D and 2D materials. The most recent advances of these materials including synthetic routes, optoelectronic properties, self-organising properties, and potential applications will be discussed.

References

[11] L. Jiang, A.C. Papageorgiou,* S. Cheol; Ö. Sağlam, J. Reichert,* D.A. Duncan, Y.-Q. Zhang, F. Klappenberger; S. More, R. Bhosale, A. Mateo-Alonso* and J.V. Barth ACS Nano
2016,DOI: 10.1021/acsnano.5b06340. [10] A. Mateo-Alonso Chem. Soc. Rev.
2014, 43, 6311-6324. [9] A.B. Marco, D. Cortizo-Lacalle, C. Gozalvez, M. Olano, A. Atxabal, X. Sun, M. Melle-Franco, L.E. Hueso, and A. Mateo-Alonso Chem. Comm.
2015, 51, 10754-10757. [8] R. Garcia, M. Melle-Franco and A. Mateo-Alonso Chem. Comm.
2015, 51, 8037-8040.[7] R. García, S. More, M. Melle-Franco, A. Mateo-Alonso Org. Lett.
2014, 16, 6096−6099. [6] G. Tregnago, C. Fléchon, S. Choudhary, C. Gozalvez, A. Mateo-Alonso, F. Cacialli App. Phys. Lett., 2014, 105, 143304. [5] S. More, R. Bhosale, A. Mateo-Alonso Chem. Eur. J., 2014, 20, 10626-10631. [4] S. More, S. Choudhary, A. Higelin, I. Krossing, M. Melle-Franco, A. Mateo-Alonso Chem. Comm., 2014, 50, 1976-1979. [3] S. Choudhary, C. Gozalvez, A. Higelin, I. Krossing, M. Melle-Franco, A. Mateo-Alonso Chem. Eur. J., 2014, 20, 1525-1528. [2] S. More, R. Bhosale, S. Choudhary, A. Mateo-Alonso Org. Lett.
2012, 14, 4170-4173. [1] N. Kulisic, S. More, and A. Mateo-Alonso Chem. Comm.
2011, 47, 514-516.
(Invited) Polypeptides/C60 Complexes and Their Applications
Authors: Solladie Nathalie 
Published: February 2020

One of our research field concerns porphyrin-functionalized α-polypeptides to control the spatial organization of the chromophores and enable exciton migration through the pool of porphyrins to mimic the light harvesting antennae of the photosynthetic system.1

In the photosynthetic system, the solar energy is collected by pigment molecules attached to the light harvesting complexes, in which the chlorophylls are held in a parallel orientation by fairly short a-helical polypeptides. When a photon hits one of the chlorophylls, the absorbed energy spreads extremely rapidly to the others until the reaction center is reached.1 Succeeding in organizing the porphyrins in a similar way as nature does should provide information about the relation existing between the orientation of the chlorophylls and the efficiency of nature in transferring an excited state over a very long distance and with minimal loss of energy.
The right-handed 310 helical conformation adopted by our poly-L-lysine functionalized with eight porphyrins induces an overlap of the chromophores (studies realized in collaboration with Prof. T. Keiderling, University of Chicago, US), which thus present sufficient electronic coupling to promote a good exciton migration within the molecular wire.
The properties of our peptides with pendant porphyrins were studied extensively in collaboration with with Professor S. Fukuzumi (Univeristy of Osaka, Japan) and applications were found as organic photovoltaic cells,2 multiple photosynthetic reaction centers3 and for the successful purification of Single-Walled Carbon Nanotubes.4

Acknowledgements

This work was supported by the CNRS and the French Ministry of Research.

References

W. Kühlbrandt, Nature
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T. Hasobe, K. Saito, P. V. Kamat, V. Troiani, H. Qiu, N. Solladié, K. S. Kim, J. K. Park, D. Kim, F. D'Souza, S. Fukuzumi, J. Mater.
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S. Fukuzumi, K. Saito, K. Ohkubo, V. Troiani, H. Qiu, S. Gadde, F. D’Souza and N. Solladié, Phys.
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Kenji Saito, Vincent Troiani, Hongjin Qiu, Nathalie Solladié, Takao Sakata, Hirotaro Mori, Mitsuo Ohama, Shunichi Fukuzumi, J. Phys. Chem. C 2007, 111, 1194-1199.

Figure 1
(Invited) Concave Host Molecules Containing Phosphorus Atoms for Fullerenes
Authors: Yamamura Masaki , Nabeshima Tatsuya 
Published: February 2020

The recognition of fullerenes (C60 and its higher analogues) is one of the most intensive research subjects in supramolecular and host-guest chemistry. Bowl-type p-conjugated molecules, for example, corannulene or sumanene, are promising host molecules because their concave surfaces closely resemble fullerene segments and can fit precisely to the convex surface of C60. In particular, these molecules are attractive because of their potential to function as chiral hosts based on “bowl-chirality”. However, racemization easily underwent in many of chiral bowl-type molecules. We envision a strategy for the design of a chiral concave molecule using a phosphorus-doping method, which can play a crucial role in construction of the concave structure. We now report the synthesis of the chiral concave molecule by extension of the p-surface ofphosphorus-containing concave molecule.
We synthesized the C
3-symmetric chiral concave mole-cule having a phosphorus atom at the center and resolved the enantiomers. The chiral concave structure was revealed by X-ray analysis. The concave molecule exhibited strong CD signals with a large anisotropy, the detail of which was confirmed by TD DFT calculation. In the co-crystal with C60, four molecules of enantiopure perfectly wrapped the surface of C60. MALDI-TOF mass and NMR spectra also supported the concave-convex interaction between the host molecule and C60. Furthermore, the observa-tion of the ICD signal of the guest fullerene indicates the transfer of the chiroptical properties of the host molecule to the guest. These results suggest that the chiral host is a component of a chiral self-assembled host for C60. The self-assembly of the concave molecules and the properties of the host-guest complex with fullerene will be presented.

Figure 1
(Invited) Physics of Electronic Transport in Low-Dimensionality Materials for Future FETs
Authors: Fischetti Massimo V 
Published: February 2020

The scaling of electronic devices has continued unabated for the past 5 decades, despite repeated predictions of the "end of scaling". The "more than Moore" slogan has been, and still is, viewed by industry as a need to explore realistic low-to-medium-risk avenues, some already in production -- such as strained Si/Ge or high-κ dielectrics, some yet to be translated to products in the near future or never -- such III-V semiconductors or tunnel-FETs. On the contrary, Academia has looked far ahead, even beyond carbon-based electronics (carbon nanotubes, graphene, nanoribbons). Now that the ULSI technology is looking at a feature size of 5 nm by 2026, even more “improbable” alternatives are considered, including transition metal dichalcogenides (TMDs), silicene/ane, germanene/ane (together with other *enes and *anes), topological insulators, Weyl semimetals, and other strongly correlated fermion systems.
Here I will first discuss the fact that, if we really wish to scale to 5 nm, simple electrostatic scaling laws demand that we take two-dimensional materials very seriously, despite their thermodynamic instability (Mermin-Wagner theorem) and the related technological difficulties. I will first consider how electronic transport in non mirror-symmetric 2D crystals (e.g., silicene, germanene, stanene, TMDs of the 1T/T’ crystal structure) may be severely affected by coupling of the electrons with the acoustic flexural modes (ZA-phonons). I will then consider whether graphene has any chance of replacing Si by looking at how the extremely promising electronic properties it exhibits in its ideal form become much less interesting when it becomes a component of some non-ideal structure (such when supported and gated and/or in nanoribbon form). Finally, I will discuss a couple of very interesting admittedly improbable but fun ideas: 1. The Bose-Einstein condensation in bilayer systems (motivating UT-Austin’s BiSFETs) as an example of how issues of practical implementation may regrettably transform an excellent idea into a pure academic exercise; and 2. Monolayer tin (“stannanane”) as a 2D topological insulator with potential applications in spintronics and low-power high-performance devices (… assuming we can make it, of course…). For the entire discussion I will keep density functional theory (DFT), empirical pseudopotentials, and transport equations in the background.
This work qas done in collaboration with Shela Aboud, Bo Fu, Jiseok Kim, Sudarshan Narayanan, Ana Suarez Negreira, Zhun-Yong Ong, Cathy Sachs, and William Vandenberghe.
Enzymatic Glucose Biofuel CELL Based on Graphene
Authors: Bagheri Samira 
Published: February 2020

Nowadays, by increasing the amount of implantable devices with high variety of applications, supplying their required energy to sense, monitor, vibrate, pump and report the collected data, has concerned the scientists and engineers around the world. This power source should be environmentally friendly with long life time and even implantable as well as capable of producing energy from the living organisms’ fluids. These required properties, light up the idea of using enzymatic biofuel cells (EBFCs) to generate the power. Unfortunately, EBFCs are limited by their short life time and poor electron transfer from the enzyme active site to the electrode surface. Recent studies have indicated that 3D graphene is a relatively novel material with unique properties that could make it useful in enzymatic biofuel cells. The graphene offers high electrical conductivity and high porous structure. According to recent studies carbon nanostructures can be used widely to immobilize the enzymes and transfer the electron from enzyme active site to the electrode surface as well. In this proposed research project, graphene oxide will be synthesised via the simplified Hummers method and then reduced into three dimensional graphene. However, the high efficiency of 3D graphene-enzyme biocomposite in a biofuel cell requires a suitable porous architecture that maximizes the enzyme immobilization at nanostructure and increase the electron transfer. In order to further increase the efficiency of biofuel cell, considerable effort has to be exerted to improve the enzyme lifetime and the amount of transferred electron. It has been well-established that immobilizing the redox enzyme using the carbon nanostructures hold a number of advantages such as increasing the lifetime of enzyme, decreasing the enzyme leaking as well as enhanced electrical charge transfer properties. In this contribution, graphene hydrogel has been synthesized and used to immobilize the enzyme on the surface of the electrode for enhancement of the EBFCs generated power.
Electronic Properties of Various B-Doped Diamond(111)// Dye Molecule Interfaces
Authors: Larsson Karin Margit Eleonora 
Published: February 2020

Diamond is a widely known material for its many excellent properties (e.g., high thermal conductivity, high break down voltage, transparency, chemical intertness and bio-compatability). A B-doped diamond is an excellent p-type material for solar cell usage. Due to some specific properties (e.g., large chemical inertness, very high carrier mobility for both electron and holes, and high transparency), it is considered as one of the strongest candidates for photovoltic electric generation. However, in order to implement the usage of diamond in solar energy applications, properties like the i) electrochemical window, ii) possibility for interfacial charge transfer, and iii) stability of functionalized surface, have to be further studied and optimized.
In the present investigation, the adsorption of different dye molecules onto H-terminated diamond (111) surfaces, have been theoretically studied using Density Functional Theory (DFT) calculations under periodic boundary conditions. The diamond surfaces were B-doped in order to make them p-type semi-conducting. The choice of dyes was based on the match between the electronic structures of these H-terminated B-doped diamond surfaces, and the respective dye molecules. The dye molecules in the present study included C20H13NO3S4 (A), C35H37NO2S3 (B), C34H38OS2(C), C32H36OS2(D), and C31H35S3Br(E). These dyes differ in the various functional groups, which have the role as electron acceptors. The main goal with the present study was thereby to investigate and compare the photovoltaic efficiency of the various dyes when attached to B-doped and H-terminated diamond (111) surfaces. Of a special interest was to study the i) absorption spectra of the dye, ii) degree of electron transfer over the diamond//dye interface, iii) electron transfer rate, iv) electron-hole recombination, and v) diamond//dye bond strength.
The calculated absortion spectra for in principle all of the different dyes were shown to be located in the most intense part of the sunlight spectrum. For the E dye, the spectrum were more positioned towards the UV light range. The usage of a combination of these different dyes would, hence, be an optimal choice in order to improve the light harvesting in a photovoltaic process.
Furthermore, the calculations identified the LUMO´s for the B, C, and D dyes to be positioned on the upper end of the molecules, which also will be the position of the electron acceptor when being excited by light. For the dyes A and E, there were though certain extentions of the LUMOs to the lower end of the molecules (i.e., towards the diamond surface), which will also increase the electron-hole recombination rates.
Calculation of electron transfer was to ensure that the HOMO of these dyes were positioned at a lower energy compared to the upper edge of the valence band of the B-doped diamond surface. Moreover, all dyes were found to bind with strong C-C covalent bonds to the diamond (111) surface.