bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geobacter Sulfurreducens Biofilm Growth Kinetics on High Surface Area, Flow-through Anodes Under Ion-Transport Limitations
Authors: Harrington Timothy David , Beyenal Haluk 
Published: February 2020

Anode-respiring bacteria like Geobacter sulfurreducens have been used to generate electrical current in many different bioelectrochemical systems, including microbial fuel cells and microbial electrolysis cells. Various cell designs have led to increases in the current densities of these systems when normalized to the projected surface area of the anodes by using 3D architecture and various convection mechanisms, with the result being an increase in current density by around five-fold. However, this increase does not nearly match the increase in available surface area. We hypothesized that the surface area is in excess in these systems, and that the current density is probably limited by ion-transport. To investigate this hypothesis, we designed a flow-through, 3D anode bioelectrochemical reactor to investigate the effect of the ion-transport limitation on the growth kinetics of G. sulfurreducens.
Using our three-electrode bioelectrochemical reactor system, we ran experiments to test how the current production, acetate utilization, hydrogen production, and biomass production were affected by changing Nernst-Planck variables, including ion transport and electrode spacing. In our system, we found that ion transport can become limiting after a 3D electrode is sufficiently colonized by Geobacter sulfurreducens, and that beyond this point the growth kinetics are no longer defined by the Nernst-Monod equation. Under these conditions, we found that the maximum current is controlled by mass transport of acetate when advection is absent, and by the mass transport of ions when advection is present. We also found that on a graphite felt electrode, in a system where ion transport is limiting (i.e., when addition of salt or convection increases the current), the acetate consumption and growth kinetics of Geobacter sulfurreducens are arithmetic, with the respective rates controllable using the variables in the Nernst-Planck equation. In this arithmetic growth regime, the acetate consumption rate, hydrogen productivity and the growth rate were decoupled from instantaneous biomass, and instead coupled solely to the steady-state current. Though arithmetic growth patterns in bacteria and algae have been described historically when the cells are under certain conditions, this the first time that an arithmetic growth regime of a microorganism has been demonstrated to be caused by ion transport in an electrochemical system, and should add to our understanding of the growth kinetics of anode-respiring biofilms. The presentation will discuss the implications of our results for future reactor designs.
Vertically Aligned Carbon Nanosheets As Immobilization Supports for Enzyme Bio-Electrocatalysis
Authors: Umasankar Yogeswaran , Brooks D. Bradford , Brown Billyde , Zhou Zhiguo , Ramasamy Ramaraja P 
Published: February 2020

High performance laccase-based biofuel cell cathode has been developed using carbon nanosheet (CNS) with buckypaper (BP) as the substrate electrode. Compared to multi-walled carbon nanotubes (MWNT) based electrode, CNS based electrode exhibited better electrochemical activity for oxygen reduction reaction (ORR) at biologically relevant conditions. The scanning electron microscopy and Raman spectroscopy studies show that CNS was coated on the nano-tubule bundles within the BP. The attenuated total resonance Fourier transform infrared spectroscopy results show that laccase was intimately attached on to the CNS-BP. Electrochemical characterization including cyclic voltammetry and Tafel region sweep were performed to derive the kinetic parameters of ORR at the laccase-CNS-BP cathode. The onset potential obtained from the cyclic voltammogram for laccase ORR at CNS-BP is 20 mV higher than the MWNT based electrodes. The laccase-CNS-BP also exhibited steep ORR cathodic wave in the voltammograms with a Tafel slope of 19 mV decade-1. Steady state cathode polarization curves also reveal that laccase-CNS-BP cathode yielded higher current density than MWNT electrodes.

Fig. 1: Schematic representation of four electron transfer ORR at laccase-CNS interface.

Acknowledgements:

This work was partially supported by the United States Army under Contract No W911NF-13-C-0014.

References:

1. Ramasamy, R. P.; Luckarift, H. R.; Ivnitski, D. M.; Atanassov, P. B.; Johnson, G. R. (2010) High electrocatalytic activity of tethered multicopper oxidase-carbon nanotube conjugates. Chemical Communications., 46, 6045-6047.
2. Parimi, N. S.; Umasankar, Y.; Atanassov, P.; Ramasamy, R. P. (2012) Kinetic and mechanistic parameters of laccase catalyzed direct electrochemical oxygen reduction reaction. ACS Catal., 2, 38-44.
3. Umasankar, Y.; Brooks, D. B.; Brown, B.; Zhou, Z.; Ramasamy, R. P. (2013) Three dimensional carbon nanosheets as novel catalyst support for enzymatic bioelectrodes. Advanced Energy Materials, (accepted paper).
Photo-Electrochemical Scanning Droplet Cell for Screening of Photocatalysts
Authors: Hassel Achim Walter 
Published: February 2020

Reasearch on photocatalysts is rapidly increasing. They will hopefully help us solving or at least reducing our energy problems. Heterogeneous and homogeneous catalysts are considered in various approaches. The preparation of modified or entirely new photoactive materials requires an effective screening of the material. This is performed using the photo-electrochemical scanning droplet cell PE-SDC that was introduced in its initial form some 10 years ago [1]. The basic idea is using a glass capillary with a tip diameter of e.g. 100 µm that is wetting a small part of a substrate. An in build reference electrode guarantees a full 3 electrode arrangement. In the set up presented here various light sources can be randomly used to illuminate the investigated small spot. The light sources are either diode lasers with fixed wavelength or a continuous emitter for which the wavelength of interest is chosen using a monochromator [2].
The performance of this system is demonstrated using traditional semi conductors such as n-Si, p-Si and III-IV semiconductors proving that:
photo potential (continuous or chopped)
photo current (continuous or chopped)
photo impedance (full spectra and/or fixed frequency bias scanning)
can be automatically performed.
Material libraries of transition metal oxides have been prepared by multi source co-deposition and have been screened using the PE-SDC. This class of materials produces promising candidates for water splitting photo electrodes. In the comparison of MeOx-WOx libraries in which the metal Me is a ferrous metal like Fe, Ni or Co differences in the mechanisms are explained. There are striking differences which results form the differences in the watersplitting capacity of compositions within these libraries. What they do have in common is that they all show successful applications of a combinatorial photo-electrochemical approach in which samples are prepared and investigated in the CALMAR.
Screening of homogeneous or immobilized catalysts is an alternative application. Complex bi-functional materials with an intramolecular donor acceptor pair are rather difficult to synthesize and therefore may exist only in several 10 mg amounts in the beginning. Here it is necessary to have an efficient method for fully characterizing such materials under these limited conditions [3]. Examples will be given to prove the effectiveness of PE-SDCs
[1] A. W. Hassel, M. Seo, Localised Photoelectrochemical Measuremnets with the Scanning Droplet Cell in Passivity and Localised Corrosion, Proc. Electrochem. Soc. (1999) 337
[2] J. P. Kollender, A. I. Mardare, A. W. Hassel, “Photoelectrochemical Scanning Droplet Cell Microscopy (PE-SDCM)”, ChemPhysChem 14 (2013) 560-567
[3] J. Gasiorowski, A. I. Mardare, N. S. Sariciftci, A. W. Hassel, “Electrochemical characterization of sub-micro-gram amounts of organic semiconductors using scanning droplet cell microscopy”, J. Electroanal. Chem. 691 (2013) 77-82
Coated Tubular Ion-Selective Electrode Units in Process Systems
Authors: VAN Staden Jacobus Frederick 
Published: February 2020

Dick (Richard) Buck made his mark in 1968 in the activity on ion-selective electrodes (ISEs) on the response of solid-state membrane electrodes under zero current conditions1 and in 1974 on concentration dependent selectivity coefficients for ion-selective electrodes2. I met Dick Buck in 1985 in the UK when I gave my first lecture on the new innovation on coated tubular ion selective electrodes in flow analysis. We became friends with our involvement in IUPAC in the late 1980’s and 1990’s with his involvement in the commission on electroanalytical chemistry and mine in the commission on general analytical chemistry3-5.
In this talk different scenarios regarding the innovation, development, design, behaviour, implementation and application of coated tubular ion-selective electrode units will be outlined. The hydrodynamic conditions in process systems and especially in the conduits of flow-through process systems required special probes to fulfill the needs of these systems. The coated tubular ion-selective electrode units were designed and successfully applied in various areas and the results and performance thereof will be discussed.
References
1. R. P. Buck, Anal. Chem, 40(1) 1968, 1432-1439.
2. R.P. Buck Anal Chim Acta, 73(2) 1974, 321-328.
3. R.P. Buck, V.V. Cosofret, Pure Appl Chem, 65(8) 1993, 1849-1858.
4. R.P. Buck, E. Lindner, Pure Appl Chem, 66(12) 1994, 2527-2536.
5. J.F. van Staden, Pure Appl Chem, 71(12) 1999, 2303-2308.
Acknowledgements
The present work was supported by the Romanian National Programme
PN II, Ideas, Contract Nr. 100/27.10.2011.
Carbon Nanostructures Used for Screening in Biomedicine
Authors: Stefan-van Staden Raluca Ioana 
Published: February 2020

Carbon nanotubes, carbon onions, and C60 fullerenes were used as matrices for stochastic microsensors design. Maltodextrins, cyclodextrins and porphyrins were immobilized in the matrices to improve the stochastic behavior of the microsensors.
The “signatures” of HER-1, NSE, leptin, PAI-1 and hormones were recorded using this microsensors in stochastic mode. The “signatures” were used to identify these analytes on the diagrams obtained when whole blood was screened. Quantitative analysis was also performed using these microsensors. The results obtained using the proposed microsensors were correlating very well with those obtained using the standard methods used in clinical analysis.
Acknowledgements This work was supported by UEFISCDI PNII Program Ideas 2011-2014, Contract nr. 123/05.10.2011 and by ERC-like-3/07.2012 program.
Three-Dimensional Mesoscale Modeling of Anisotropic Mechanical Deformation in Lithium-Ion Electrodes
Authors: Roberts Scott A. , Long Kevin N. , Brunini Victor E. , Grillet Anne M. 
Published: February 2020

Capacity fade in Lithium-ion batteries is dependent on a number of processes, one of which may be physical deterioration of the electron transport network formed by the solid particles which make up the electrodes. One cause of progressive capacity deterioration is the evolution of inter-particle stresses caused by cyclic swelling processes from intercalation and phase transformations. Intercalation reactions as lithium insert into the crystal lattice lead to anisotropic deformation and complex mechanical behaviors on the mesoscale.
In this presentation, we demonstrate our recent efforts in performing three-dimensional simulations of Lithium-Ion electrode materials at the mesoscale, with hundreds of particles included. Our focus will be on anisotropic mechanical deformation, with additional physics (such as thermal and species transport) included to appropriately drive the mechanical deformation. The simulations will include anisotropy within individual particles and demonstrate stochastic initiation of lithiation. This simulation approach will be deployed on multiple configurations, including spherical particles packs generated from measured particle size distributions and reconstructed geometries from FIB-SEM cuts of actual electrode materials.

* Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.
Simulation of Macro Scale Mechanical Behavior of Pouch Cell Lithium-Ion Batteries
Authors: Smith Kandler , Maute Kurt , Behrou Reza , Santhanagopalan Shriram 
Published: February 2020

Electrochemical energy storage devices suffer from capacity fade due to mechanical, thermal and electrochemical interaction. This study focuses on mechanical phenomena in lithium ion pouch cell batteries. A finite element model is developed to predict swelling/shrinking in cathode/anodes due to thermal expansion and lithium intercalation, as well as in-plane and out-of-plane deformation. Transport of lithium, transport of heat and generation of heat are obtained through measurement or numerical simulations.
Pouch cell batteries are composed of a large number of individual thin layers which are stacked together. To correctly capture the plate-like behavior of individual layers while limiting the in-plane discretization, a computational mesh with large aspect ratio elements is needed. As such elements may suffer from spurious stiffening effects a high performance finite element formulation is developed. This small-strain, solid-shell finite element formulation accurately captures both the in-plane and out-of-plane behavior of individual layers.
Figure 1 below shows a cross section of the pouch cell mesh resolving indivdual layers and folder separator construction.
Synthesis of the Materials Used in All-Solid-State Lithium Secondary Batteries
Authors: Matsumoto Takuto 
Published: February 2020

Conventional electrolytes in Li-ion batteries based on organic solvents or polymers with a dissolved Li-salt pose serious limitations such as flammability, difficulty of miniaturization, and serious impact to the environment if poorly disposed of or recycled.
As a replacement, stable inorganic solid electrolyteswith high Li conductivity and suppressed electronic conductivity has become increasingly appealing, with several advantages including nontoxicity, ease of preparation, and low cost.
So far, Li ion conductors with garnet-type structure are considered as promising electrolytes because of their high conductivity and excellent stability.
Li7La3Zr2O12 (LLZO) has recently become of high interest as a result of its potential as a solid state Li-ion conductor, because it has good ionic conductivity (>10−4 S/cm) and is stable against lithium. However, for the case of LLZO two phases exist; cubic and tetragonal.
The cubic phase is preferred, because reports estimate a theoretical lattice conductivity of ~5×10-4 S/cm compared to ~1.6×10−6 S/cm, for the tetragonal phase.
Thus, it is important to understand how to prepare the cubic phase.
In general, calcination temperatures in excess of 1180 °C are required to obtain cubic LLZO.
In this study, we aim to synthesis of cubic LLZO using a hydrothermal synthesis method.
Mechanical-Electrochemical Coupling in Materials for Solid Oxide Fuel Cells: Insights from Computer Simulations
Authors: Marrocchelli Dario , Bishop Sean R. , Tuller Harry L. , Yildiz Bilge , Watson Graeme 
Published: February 2020

The coupling between the electrical, chemical and mechanical properties of materials, usually referred to as Electro-Chemo-Mechanics [1], has very important implications for energy related materials and devices. Indeed, this coupling can be beneficial, e.g. the ion conductivity enhancement observed in ceria and zirconia when these materials are strained [2], or detrimental, e.g. the lattice parameter expansion observed in ceria upon reduction [3]. For this reason a better understanding of this coupling is necessary in order to tailor the properties of these materials.
Atomistic computer simulations represent a powerful tool to study the mechanical-electrochemical coupling, as they can provide information that is complementary to experiments. In this presentation, I will review some recent computational work in this field. First I will talk about chemical expansion in ceria, an example of chemo-mechanical coupling. I will show how, by combining Density Functional Theory and Molecular Dynamics Calculations with experimental data, we concluded that chemical expansion is caused by two competing processes, the formation of a vacancy (leading to a lattice contraction) and the cation radius change (leading to a lattice expansion). This information was then condensed in a simple analytical model, which was then used to predict materials compositions that minimize chemical expansion. Then I will present two more examples from my work: the first one on the study of co-doping strategies in ceria as a means to enhance its ionic conductivity (electro-chemical coupling) and the second one on the effects of dislocations in SrTiO3 on the defect chemistry and mobility of this material (electro-chemo-mechanical) coupling.
References
[1] Tuller and Bishop, Annu. Rev. Mater. Res.
41 369 (2011)
[2] Kushima and Yildiz, J. Mat. Chem. 20 4809 (2011)
[3] Marrocchelli et al. Adv. Fun. Mat.
22 1958 (2012)
Invited Presentation: Chemical Strain Kinetics in Epitaxial Thin Films Measured By Time-Resolved X-Ray Diffraction
Authors: Santiso Jose , Moreno Roberto , Zapata James , Roqueta Jaume , Garcia Pablo 
Published: February 2020

The study of the chemical strain kinetics induced by oxygen surface exchange in transition metal oxides is of increasing relevance for understanding the fundamental mechanisms for oxygen reduction and evolution reactions (ORR/OER) of oxide catalysts as well as for novel cathode materials for intermediate-temperature solid oxide fuel cell (SOFC) technology.
In most transition metal oxide materials the variation in the oxygen stoichiometry produced by oxygen exchange with the atmosphere is often accompanied by subtle cell volume changes, the so-called chemical strain. Generally, the incorporation of charged defects (oxygen vacancies or interstitials) is expected to cause a cell expansion from the equilibrium intrinsic cell because of variations in the radii of the transition metal ions as well as Coulomb repulsion between those defects. Any slight variation in the oxygen content would proportionally result in a measurable volume increase. The ability to dynamically follow the cell volume variations allows establishing a direct correlation with oxidation/reduction kinetics.
In this talk we will describe recent development of a new methodology to analyze chemical strain kinetics in epitaxial thin films after redox cycling by using X-ray diffraction time-resolved measurements in conventional lab diffractometer [1], as depicted in Fig 1(a). With this technique we have been able to measure average cell parameter changes as small as 0.1 ppm in a time scale of a few seconds in a wide variety of SOFC cathode materials like La2NiO4+δ, Ba0.5Sr0.5Co0.8Fe0.3O3-δ, La0.8Sr0.2CoO3-δ, and GdBaCo2O5+δ, as well as in epitaxial bilayers. Some of the results of the oxidation kinetics for the different cathode materials are depicted in the Arrhenius plot in Figure 1(b).
We will analyze the suitability of those materials for their application as cathode materials in intermediate-temperature SOFC. We will also describe the usefulness of this methodology as complementary to other well-established techniques such as Electric Conductivity Relaxation (ECR) and 18O Isotopic Exchange Depth Profiling (IEDP) experiments.
[1] R. Moreno, P. García, J. Zapata, J. Roqueta, J. Chaigneau and J. Santiso, Chem. Mater. 25 (2013) 3640-3647
Specific DNA Sequences for the Purification of Single-Wall Carbon Nanotube Species in Polymer Aqueous Two-Phase Systems
Authors: Ao Geyou , Zheng Ming 
Published: February 2020

A systematic purification of single-chirality species of single-wall carbon nanotubes (SWCNT) from their synthetic mixture provides foundation for many fundamental studies and technological applications of SWCNT. Previous study demonstrated a robust separation of SWCNT dispersed in bile salt surfactants according to their diameter and metallicity in a polymer aqueous two-phase (ATP) system. In this work, specific DNA sequences were utilized as an effective approach for recognition of specific SWCNT chirality and their subsequent purification using the ATP separation method. We show that many single chirality SWCNTs in a synthetic mixture can be obtained in very high purity.
The combination of DNA sequence recognition of specific SWCNT structure and the rapid and tunable ATP separation method open a new route for sorting nanotube into each and every single-chirality species. In addition, the feasibility of volume scale-up in ATP separation allows sufficient materials to be obtained for fundamental studies and application development. Further exploration of DNA recognition sequences in ATP separation method and new polymer ATP systems will be the main focus of our future studies in carbon nanotube sorting.
Novel Terbium-Based Endohedral Clusterfullerenes: Synthesis, Isolation and Characterization
Authors: Yang Shangfeng 
Published: February 2020

Fupin Liu1, Tao Wei1, Song Wang1, Jian Guan1, Xing Lu2, and Shangfeng Yang1*

1 Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Materials for Energy Conversion & Department of Materials Science and Engineering, University of Science and Technology of China (USTC), Hefei 230026, China

Email: sfyang@ustc.edu.cn

2 State Key Laboratory of Materials Processing and Die & Mould Technology, College of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China

Clusterfullerenes as a special branch of endohedral fullerenes are characteristic in the encapsulation of an unstable metal cluster by a robust fullerene cage.[1,2] We present here several novel Tb-based endohedral clusterfullerenes isolated successfully recently. Tb2C84 was isolated by multistep HPLC. According to the UV-vis-NIR spectroscopic characterization and comparison with the reported analogous M2C84 (M = Sc, Y) metallofullerenes, the molecular structure of Tb2C84 is proposed to be Tb2C2@Cs
(6)-C82 featuring a metal carbide clusterfullerene (CCF) structure, which is unambiguously confirmed by X-ray crystallographic study. A detailed analysis of the crystal structure of a cocrystal of Tb2C2@Cs
(6)-C82·NiII(OEP)·2C6H6 (NiII(OEP) = nickel (II) octaethylporphyrin) reveals that a bent Tb2C2 carbide cluster is encaged rigidly inside a Cs
(6)-C82 cage.[3] More recently we also successfully isolated the first Tb-based monometallic cyanide clusterfullerene (CYCF), TbCN@C82. The UV-vis-NIR spectrum and cyclic voltammetry of TbCN@C82 show high resemblance to those of the recently reported analogous CYCF YCN@Cs
(6)-C82,[4] suggesting that TbCN@C82 has the same monometallic cyanide clusterfullerene structure and Cs
(6)-C82 isomeric cage, and the electronic property of monometallic cyanide clusterfullerene MCN@C82is insensitive on the encapsulated metal.
REFERENCES

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a) A. A. Popov, S. F. Yang, L. Dunsch, Chem. Rev.
2013, 113, 5989-6113; d) S. F. Yang, C. R. Wang (eds), “Endohedral Fullerenes: From Fundamentals to Applications”, World Scientific Publishing Co., Singapore, 2013 (ISBN: 978-9814489836); c) S. F. Yang, Curr. Org. Chem.
2012, 16, 1079-1094; d) A. Rodriguez-Fortea, A. L. Balch, J. M. Poblet, Chem. Soc. Rev.
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F. P. Liu, T. Wei, S. Wang, J. Guan, X. Lu, S. F. Yang, Fullerenes, Nanotubes and Carbon Nanostructures
2013, 21, in press (DOI: 10.1080/1536383X.2013.801839).

S. F. Yang, C. B. Chen, F. P. Liu, Y. P. Xie, F. Y. Li, M. Z. Jiao, M. Suzuki, T. Wei, S. Wang, Z. F. Chen, X. Lu, T. Akasaka, Sci. Rep.
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