bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon-Rich Silicon Oxycarbide - a Promising Anode Material: Recent Findings Related to Microstructural, Electrochemical and Electroanalytical Characterization
Authors: Kaspar Jan , Graczyk-Zajac Magdalena , Riedel Ralf 
Published: February 2020

The electrochemical properties of silicon oxycarbide ceramics (SiOC), in view of application as anode material for Li-ion batteries, were first studied in the middle of the 1990’s by Dahn et al. [1,2]. Since that time SiOC compounds with various chemical compositions have been examined and stoichiometries with an exceptionally high content of free carbon were identified as perspective anode materials, with respect to gravimetric capacity, rate capability and cycling behavior [3-6].
Within this work, the comprehensive characterization of carbon-rich SiOC derived from commercially available polyorganosiloxane RD-684a (Starfire Systems Inc., USA) is presented. The overview includes the correlation of electrochemical properties with microstructural features in dependence of the ceramization temperature of the Si-based polymer [6]. The dependency of the Li-ion diffusion coefficient on the potential is determined by electroanalytical methods PITT, GITT and EIS and analyzed with respect to the microstructural features of the ceramic [7]. In addition, the benefits of chemical modification of the precursor with Sn(ac)2, in order to enhance the lithium storage properties of SiOC by in-situ precipitation of metallic Sn as additional electrochemically active phase, is highlighted [8]. Finally, our newest results from ex-situ and in-situ Raman-spectroscopy measurements are presented, which directly trace and verify the Li-ion uptake within the free carbon phase in the SiOC microstructure.

A.M. Wilson, J.N. Reimers, E.W. Fuller, J.R. Dahn, Solid State Ionics, 74 (1994) 249-254

W. Xing, A.M. Wilson, K. Eguchi, G. Zank, J.R. Dahn, J. Electrochem. Soc., 144 (1997) 2410-2416

H. Fukui, O. Hisashi, T. Hino, K. Kanamura, ACS Appl. Mater. Interf., 4 (2010) 998-1008

X. Liu, M.-C. Zheng, K. Xie, J. Liu, Electrochim. Acta, 59 (2012) 304-309

V.S. Pradeep, M. Graczyk-Zajac, M. Wilamowska, R. Riedel, G.D. Soraru, Solid State Ionics, (2013), in press

J. Kaspar, M. Graczyk-Zajac, R. Riedel, J. Power Sources, 244 (2013) 450-455

J. Kaspar, M. Graczyk-Zajac, R. Riedel, Electrochim. Acta, 115 (2014) 665-670

J. Kaspar, C. Terzioglu, E. Ionescu, M. Graczyk-Zajac, S. Hapis, H.J. Kleebe, R. Riedel, Adv. Funct. Mater., (2014), in press
Quantitative Modeling of Microbial Fuel Cells for Water Purification
Authors: Calabrese Barton Scott 
Published: February 2020

Although the 2015 Millennium Development Goal (MDG) for access to safe drinking water has largely been achieved, over 700 million people cannot access safe drinking water [1]. More importantly, the MDG for water sanitation is is far from achieved: 2.5 million people, primarily in sub-saharan Africa, lack access to water sanitization.
One solution for these populations is low-cost, mobile water purification based on microbial fuel cells (MFCs). MFCs are capable of producing energy from organic water contamination by oxidizing the contaminants, thereby producing electricity and reducing the chemical oxygen demand (COD) a key measure of water contamination, by more than 90% [2]. However, such a system would need to meet stringent cost and durability requirements; a self-powered purification system would require an approximately 10-fold increase in typical MFC power density and lifetime. Moreover, bench scale MFCs of 0.1 L size would would need to be scaled up to over 10 L for practical applications. These requirements can only be met by through careful engineering design and optimization.
Here we describe a numerical model of the the steady-state and transient operation of a microbial fuel cell for water purification. The model is based on laboratory-scale experiments conducted on MFCs using the Dissimilatory metal reducing bacteria Shewanella oneidensis MR-1 [3]. The model accounts for growth of bacterial biofilms, transport of reactants and products within the films, and related consumption of organic contaminants to electricity production.
Particular attention is paid to biofilm composition, and electron transport mechanisms with the biofilm, including electron transport via dissolved mediators, pili and nano filaments, and surface exchange. These considerations allow the the model to applied to a variety of metal-reducing species. After calibration with laboratory-scale MFC data, the model is used to predict performance of 10L-scale MFCs, including the relationship between decontamination rate, water flow rate, and power generation. Sensitivity studies may be directly compared with principal component analysis of experimental results, indicating the degree to which the model can be used for design and optimization of real-world devices.

"Millennium Development Goal drinking water target met”, http://www.who.int/mediacentre/news/releases/2012/drinking_water_20120306/en/

M. M. Ghangrekar and V. B. Shinde, Bioresour. Technol., 98, 2879 (2007). doi:10.1016/j.biortech.2006.09.050

E. Baranitharan, M. R. Khan, D. M. R. Prasad and J. Bin Salihon, Water, Air, Soil Pollut., 224, 1533 (2013). doi:10.1007/s11270-013-1533-1

S. Babanova, O. Bretschger, J. Roy, A. Cheung, K. Artyushkova and P. Atanassov, Phys. Chem. Chem. Phys., 16, 8956 (2014). doi:10.1039/c4cp00566j
Application Driven Fundamental Research on Microbial Electrochemical Technologies: From Components to System
Authors: Schroder Uwe , Harnisch Falk 
Published: February 2020

Microbial electrochemistry is the study and application of interactions between microbial cells and electron conductors (electrodes). For a long time this field of bioelectrochemistry has been the interest of only fundamental researchers. This has significantly changed during the last decade, in which microbial electrochemistry gained increasing interest from applied researchers and engineers. Among other types of potential application, these researchers developed microbial fuel cells (MFCs), microbial electrolysis cells (MECs) and microbial desalination cells (MDCs) – electrochemical systems that utilize the organic load in wastewater to produce electric power, to produce chemical compounds or to desalinate salt water, respectively. However, the great majority of research on full systems is still being performed at laboratory scale (less than 1 L reactor volume) and technical or even pilot scale studies are rare. Rationally the majority of current studies do not focus on the system scale, but on the advancement of components, e.g. electrodes and membranes, and the investigation of fundamental processes of these components, e.g. interactions in microbiomes formed at electrodes, aiming at their subsequent engineering. However, system scale studies have clearly revealed a substantially higher degree of complexity and thus achievements on the component scale often cannot be simply transferred.
Therefore, we advocate that the most important issue is wisely merging fundamental research at the component scale with full system development. In this presentation we will illustrate on selected, recent examples the rationale of our appeal, spanning from very fundamental aspects like the development of high-performance electrode materials via the removal of micropollutants from wastewater at laboratory scale to a recent technical scale demonstrator and its performance in cleaning municipal wastewater and nitrogen recovery.
Engineering of Microbial Fuel Cells: The Things We Need to Know to Move Forward
Authors: Babanova Sofia , Bretschger Orianna , Artyushkova Kateryna , Atanassov Plamen 
Published: February 2020

Microbial fuel cells (MFCs) provide a unique opportunity to combine the advantages of two worlds, wastewater purification and electricity production, that can be successfully explored for the development of self-sustainable portable wastewater plants. Unfortunately the level of development of this technology is just heading into the list of the practical devices. A significant part of the efforts in this area has been associated with fundamental understanding of the operational laws behind MFCs. Now, when the pile of knowledge regarding biofilm formation, electrode respiration by bacteria, biological interfacial reactions, etc. reached significant level, the next step in the scale-up process should involve material and design optimization. By looking back at what has been developed so far using innovative statistical interpretation of data, a numerous conclusions regarding bacteria features, metabolic pathways, electrode characteristics and MFC design can be withdrawn. Based on these conclusions, and mainly based on the observed correlation between parameters, a model describing MFC operation was created. This model included sub-modules describing the bacterial community, bacteria-electrode interactions, material properties as well as MFC overall design parameters[
1
].
The major factors influencing MFCs was recognized through Principal component analysis and their ascendency over MFC operational characteristics was statistically evaluated. The outputs of this analysis were further used as inputs for the development of a mathematical model, combining those factors. Path analysis was the main analytical tool for the model establishment. The model was first developed for pure culture of Shewanella oneidensis and expanded to include mixed communities naturally occurring in wastewater, which makes this study unique.
Successful engineering of MFCs, or other bioenergy systems, requires understanding of the underlying physical and biological processes, materials and abiotic structures, and the technical limits of their implementation in practical devices. This presentation will chart our strategies in bioenergy device design at all these four technology levels.
[1] a) S. Babanova, O. Bretschger, J. N. Roy, A. Cheung, K. Artyushkova and P. Atanassov, Phis.Chem.Chem.Phys.
2014, doi: 10.1039/C4CP00566J; b) C. Santoro, M. Guilizzoni, J.P. Correa Baena, U. Pasaogullari, A. Casalegno, B. Li, S. Babanova, K. Artyushkova, P. Atanassov, Carbon
2014, 67, 128–139.
Electrochemical Disinfection of Liquid Human Waste for Developing World Application
Authors: Rogers Tate , Jackson Kathryn , Flynn Michael , Stoner Brian R. , Rowe Brfent R 
Published: February 2020

This research reports the continued development of an electrochemical disinfection (ED) system for the treatment of liquid human waste. The system is a portion of a modular toilet designed for developing countries that will not require piped-in water, a sewer connection or outside electricity. Raut et al. (1) demonstrated the ability of the ED system to completely disinfect synthetic urine spiked with E. coli. This study reports the disinfection and total chlorine production capabilities of the system using field simulated conditions. The ED system is designed to treat liquid waste that has been separated from the solid waste deposited into the toilet. The effluent will contain urine, a small amount of fecal matter (~ 0.5% w/w), flush water, and cleansing water. This liquid waste will be treated to standards suitable for discharge to soil or for reuse as rinse or flush water.
The ED system was tested with the expected daily output of urine and flush water from one person and the solids/liquids interaction with feces was simulated to obtain the desired fecal contamination. E. coli was chosen as the disinfection indicator with starting concentrations ranging from 2.5 x 104 – 1.4 x 107 MPN/mL. As shown in Figure 1, disinfection was achieved by 110 minutes of processing time at 12 V.
Effective treatment of pathogens is expected to be a function of the production of chlorine containing species and other reactive oxygen species. However, to maintain disinfection in the system after ED treatment, a residual chlorine concentration is desired. Figure 2 shows the total and free chlorine produced over long electrochemical cell run times. Large amounts of chlorine were shown to be produced, however; most is consumed within 24 hours after the cell is turned off.
The ED system has demonstrated effective disinfection of fecal-contaminated liquid waste in simulated field conditions. Continued research will include pilot testing and demonstration of the ED’s effectiveness at killing chlorine resistant pathogens.

Acknowledgements

Financial support for this work was provided by the Bill & Melinda Gates Foundation.

References

1. A. Raut, G.B. Cunningham, C.B. Parker, B.R. Stoner and J.T. Glass, in 223rd ECS Meeting (May 12-17, 2013).
Coaxial Nanotube Battery inside Single Nanopore
Authors: Liu Chanyuan , Gillette Eleanor , Chen Xinyi , Pearse Alexander J , Kozen Alexander C , Schroeder Marshall A , Gregorczyk Keith , Lee Sang Bok , Rubloff Gary W 
Published: February 2020

We report here a nanobattery comprised of nanotubular electrodes and electrolyte confined within an anodic aluminum oxide (AAO) nanopore. To construct confined electrically insulating electrolyte space in batteries with aligned nanoelectrodes, we have used atomic layer deposition (ALD) to synthesize nanotubular, heterogeneous coaxial electrodes at both ends of AAO nanopores. The nanoelectrodes include Ru nanotube current collectors with V2O5storage material on top of the Ru to form a symmetric full storage cell, with anode and cathode separated by an electrolyte region.
The V2O5 is prelithiated at one end to serve as anode while pristine V2O5 at the other end serves as cathode, so that the battery can be asymmetrically cycling between 0.2V and 1.8V. Capacity retention at high power (relative to 1C values 178mAh/g) is 95% at 5C and 46% at 150C. At 5C rate (12 min charge-discharge cycle), 81.3% capacity remains after 1000 cycles. The importance of incorporating integrated current collectors is demonstrated by the rate performance of V2O5 cathode with Ru nanotube current collector as compared to a Au planar current collector. While both show similar capacity at low rate (1C), at high rates (150C) that demand fast electron transport the V2O5/Ru nanotube (78mAh/g) exhibits almost twice the capacity of the V2O5/planar Au (42mAh/g).
This nanopore battery poses an extreme case of highly confined organic electrolyte environments in ultrasmall batteries. These promising results demonstrate the importance of integrating current collectors with storage nanoelectrodes, the benefit of electrolyte-accessible surface area of the nanotubular electrodes, and the cycling robustness of the nanostructures. At the same time, they provide a valuable data source for fundamental modeling to understand and quantify a science of “nanoionics” – a mesoscale phenomenon resulting from dense packing of ion storage nanostructures.
Co-Sinterable Lithium Garnet-Type Oxide Electrolyte with Cathode for All-Solid-State Lithium Ion Battery
Authors: Ohta Shingo , Kihira Yuki , Asaoka Takahiko 
Published: February 2020

Lithium ion secondary batteries have been widely used as power sources for electric vehicle (EV), a mobile phone and etc., and are now indispensable for our daily lives.At the same time, safety of the batteries has been becoming an important issue with the progress of their performance, which recently motivated the researches on all-solid-state lithium ion batteries using solid electrolytes due to non-use of flammable organic liquid electrolytes. Especially, increasing attention has been paid to the use of garnet-type metal oxides (e.g. Li7La3Zr2O12 (LLZO) and its derivatives) as a solid electrolyte due to not only good chemical stability and high lithium ion conductivity but also the potential to construct a bi-polar structure for high capacity by a simple co-sintering process. However, it has been quite difficult to suppress chemical reactions of the electrolyte with an electrolyte during co-sintering, and it is now one of the most important issues to significantly lower the sintering temperature of the electrolyte.
We investigated the development of a novel garnet-type oxide electrolyte, which is co-sinterable with a LiCoO2 cathode, based on the strategy to enhance interdiffusion between LLZO grains and grain boundariesby an appropriate selection of dopants in LLZO and additives. The sintering temperature of LLZO drastically decreased to 790 oC with maintaining high lithium ion conductivity but without the reaction with a metal oxide cathode (LiCoO2).
In addition, an all-solid-state lithium ion battery was successfully prepared by co-sintering of the stacked cathode/electrolyte layer, and confirmed to function well as a secondary battery. These results opened the potential for fabrication of all-solid-state lithium ion batteries using oxide electrolytes by a simple and well-established co-sintering process.
Tuning Energy Band and Local Crystal Structure of Photocatalysts By Doping
Authors: Zhang Junying , Li Min , Wu Nick 
Published: February 2020

The energy band configuration is a critical factor that governs the photocatalytic activity of semiconductors. Elemental doping of semiconductors could introduce the local states in the mid-gap or shift the conduction band minimum and/or the valence band maximum. Therefore, doping can modulate the light absorption spectra and alter the photocatalytic activity. We have studied the effects of different doping strategies on the energy band configuration, the local crystal structure and the photocatalytic activity in different semiconductors such as TiO2, AgTaO3, Bi2O3 and La2Ti2O7using the first-principle calculation. It has been found that isovalent mono-doping leads to slightly tuning of the energy band configuration and the local crystal structure. Aliovalent mono-doping usually induces the localized energy bands in the forbidden gap, which often reduces the photocatalytic activity. Compensated co-doping is an effective approach to improve the photocatalytic activity via narrowing the band gap without generating the localized energy band.
[1]. Min Li, Junying Zhang, Yue Zhang, Catalysis Communications 29 (2012) 175
[2]. Min Li,Junying Zhang,Wenqiang Dang, Scott K. Cushing, Dong Guo, Nianqiang Wu, Penggang Yin, Phys. Chem. Chem. Phys. 15(2013)16220
Generation and Injection of Hot Plasmonic Electrons from Optically-Excited Metal Nanocrystals for Photocatalysis and Solar Energy Applications
Authors: Govorov Alexander , Zhang Hui , Gun'ko Iouri 
Published: February 2020

We investigate the effect of plasmon-assisted carrier injection from metal nanocrystals to a semiconductor contact or to adsorbed molecules. We treat the problem of optically-driven metal nanocrystal using the quantum approach of equation of motion of density matrix. The energy distribution of optically-excited plasmonic carriers is very different in metal nanocrystals with large and small sizes. In large nanocrystals, most excited carriers have very small energies and the electron distribution resembles the case of a plasmon wave in bulk. For gold nanocrystal with smaller sizes (less than 20nm), the energy distribution of hot carriers becomes flat and has a large number of carriers with high energy [1-3]. Therefore, smaller nanocrystals are preferable for injection of plasmonic carriers into semiconductors or into molecules on the surface. The physical reason for the above behavior is non-conservation of momentum in a nanocrystal. The geometry, type of metal, and orientation of the external electric field are important to obtain high quantum efficiencies of generation and injection of plasmonic electrons [2,3]. Other important properties and limitations: (1) intra-band transitions are preferable for generation of energetic electrons and dominate the absorption for relatively long wavelengths (approximately >600 nm), (2) inter-band transitions efficiently generate energetic holes and (3) the carrier-generation and absorption spectra can be significantly different [2,3]. The results obtained in this study can be used to design a variety of plasmonic nanodevices based on hot electron injection for photo-catalysis, light-harvesting, and solar cells.
[1] A. O. Govorov, H. Zhang, Y. K. Gun'ko, J. Phys. Chem. C 117, 16616 (2013);
[2] H. Zhang, A. O. Govoro, J. Phys. Chem. C, doi: 10.1021/jp500009k (2014).
[3] A.O. Govorov, H. Zhang, V. Demi, and Y. K. Gun’ko, Nano Today, doi: 10.1016/j.nantod.2014.02.006 (2014).
Interfacial Engineering for Efficient Solar Water Splitting
Authors: Vayssieres Lionel 
Published: February 2020

With climate change seriously endangering our environment, security and health, the expected shortening in fossil fuels and sharp increase in energy demand from emerging countries, a substantial worldwide renewed interest in the field of materials for solar energy conversion has occurred within the last few years. However the high cost of energy production and relatively low efficiency of currently used systems pose an intrinsic limitation. (R)evolutionary materials development is required to achieve the necessary dramatic increases in power generation and conversion efficiency and so at low cost and large scale.
A general strategy for the modeling, design and fabrication of low cost metal oxide heteronanostructures consisting of quantum dots and oriented quantum rods-based large bandgap semiconductor structures and devices by low cost aqueous chemical growth will be demonstrated.
Synchrotron-based x-ray spectroscopies studies along with DFT calculation have been carried out to probe and engineer the interfacial electronic structure, confinement effects and orbital character and symmetry of the band edges and bandgaps as well as surface chemistry of advanced oxide heteronanostructures. The results reveal important fundamental and applied knowledge of direct relevance for semiconductor technologies such as photovoltaics and photocatalysis. Structure-property relationships as well as efficiency optimization of novel low cost nanodevices based on quantum-confined metal oxide nanostructures and heterostructures for renewable hydrogen generation from seawater splitting as well as other devices will be presented.