bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modified Ca-Graphite Intercalation Compounds As Anode Material for Li Ion Batteries
Authors: Miyamae Ryohei , Tei Go , Kano Akira 
Published: February 2020

Due to the increasing demands for the high capacity lithium ion batteries (LIBs) for use in mobile devices and electric vehicles, a new anode material with a higher capacity than that of graphite (372 mAh/g) is desired. As a candidate of such anode material, alloy-type anode (Si, Ge, Sn, etc.) shows much higher capacity than that of graphite [1]. However, their large volume modification during the charge-discharge process limits their cyclic performances. On the other hand, high capacity carbon based materials, such as graphene sheets, carbon nanotubes and nanofibers have also attracted much attention [1]. For practical use, their high intercalation potential of lithium and the difficulty of mass-production of these materials have to be overcome.
In this study, we report a new type of high capacity carbon based material, Ca0.6-xB1.2C4.8. It is a novel material obtained by one-pot heat-treatment of graphite with boron and calcium sources. Its highly ordered graphite-like layer structure distinguishes it from the former reported high capacity carbon based materials, such as graphene sheets, carbon nanotubes and nanofibers. Its specific capacity was 552 mAh/g, which is much higher than that of graphite. This result suggests the possibility of realizing a yet higher capacities for graphite based materials. The detailed preparation method, characterization, and electrochemical measurements will be discussed on the session.
References
[1] Goriparti et al., J. Power Sources, 257, 421-443 (2014)
Electrochemical Stability of Pt Nanoparticles Supported on a Wide Library of Carbon Supports, Either Used Bare, or Modified By Fluorination or Tin Oxide Deposits
Authors: Asset Tristan , Ahmad Yasser , Labbé Fabien , Batisse Nicolas , Dubois Marc , Guerin Katia , Berthon-Fabry Sandrine , Metkemeijer Rudolf , Dubau Laetitia , Maillard Frederic , Chatenet Marian 
Published: February 2020

Throughout the years, a lot of effort has been devoted to improve the electrochemical activity and stability of Pt-based electrocatalysts for the oxygen reduction reaction (ORR), moving from Pt nanoparticles (NPs, diameter ~ 2 – 3 nm) to complex nanostructured materials (i.e. Pt-based hollow, nanoframes or core@shell nanoparticles 1–3). Most of these nanostructures remain more efficient when supported onto a support, as this results in an enhanced specific surface area and, thus, an enhanced mass activity. As such, the nature and the intrinsic stability of the carbon support cannot be ignored, in particular in terms of durability. Here, we investigated (i) the activity of Pt NPs on different carbon supports (with various degrees of graphitization, specific surface area and surface treatments) and (ii) their stability during load (15,000 step cycles between E = 0.6 V vs. RHE and E = 1.0 V vs. RHE) or start-stop (1,000 step cycles between E = 1.0 V vs. RHE and E = 1.5 V vs. RHE) protocols. To that goal, a combination of complementary experiments (electrochemistry, transmission electron microscopy and Raman spectroscopy) were used. As an example, Figure 1 shows the evolution of the specific activity for the ORR measured at E = 0.95 V vs. RHE before and after the load-cycle ageing procedure.
(1) Dubau, L.; Asset, T.; Chattot, R.; Bonnaud, C.; Vanpeene, V.; Nelayah, J.; Maillard, F. ACS Catal.
2015, 5, 5333–5341.
(2) Chen, C.; Kang, Y.; Huo, Z.; Zhu, Z.; Huang, W.; Xin, H. L.; Snyder, J. D.; Li, D.; Herron, J. A.; Mavrikakis, M.; Chi, M.; More, K. L.; Li, Y.; Markovic, N. M.; Somorjai, G. A.; Yang, P.; Stamenkovic, V. R.; Samorjai, G. A.; Yang, P.; Stamenkovic, V. R.; Somorjai, G. A.; Yang, P.; Stamenkovic, V. R. Science
2014, 343, 1339–1343.
(3) Oezaslan, M.; Hasché, F.; Strasser, P. J. Phys. Chem. Lett.
2013, 4, 3273–3291.

Figure 1
Impact of Heat Treatment on the Electrochemical Properties of Octahedral Pt-Ni Nanoparticles
Authors: Xiao Fei , Shao Minhua 
Published: February 2020

Pt is still the most used catalyst for various electrocatalytic reactions. But its high cost and scarcity hinder its wide application. In order to address this problem, researchers found that alloying Pt with one or more transition metals such as Ni, Fe or Co can enhance its activity via maximizing the exposure of (111) facets.1 Octahedral Pt-Ni nanoparticles have been regarded as promising electrocatalyst for various reactions.2-4 It has been found that post heat annealing on the Pt-Ni octahedra plays a significant role in altering their activity and durability during oxygen reduction reaction.
5

In this study, the structure evolution and compositional segregation were systematically studied during annealing in various atmosphere (vacuum, N2, H2, Ar and air) by XRD, TEM, XPS and electrochemical techniques. The impact of the heat treatment on the activities toward oxygen reduction reaction, hydrogen evolution reaction, and ethanol electro-oxidation reaction were assessed. It is interesting to find that the carbon support might be unstable in certain atmosphere, for example, Ar, and can be deposited on the catalyst surface. Figure 1 compares the CVs of Pt-Ni treated in Ar and N2 at 400 °C with the unannealed one. It is clear that the surface area of Pt-Ni treated in Ar diminished due to carbon coating.
In this talk, the composition and structural evolution result upon annealing will be presented. Their effects on various electrochemical reaction activities will be discussed.
Figure 1. Comparisons of cyclic voltammograms of Pt-Ni annealed in N2 (blue), Ar (red) at 400°C for 30 min, and un-annealed one in an N2-saturated 0.1 M HClO4 solution.

Reference:

Stamenkovic, V. R.; Fowler, B.; Mun, B. S.; Wang, G.; Ross, P. N.; Lucas, C. A.; Marković, N. M. Science
2007,
315 (5811), 493-497.

Sulaiman, J. E.; Zhu, S.; Xing, Z.; Chang, Q.; Shao, M. ACS Catalysis
2017,
7 (8), 5134-5141.

Choi, S.-I.; Xie, S.; Shao, M.; Odell, J. H.; Lu, N.; Peng, H.-C.; Protsailo, L.; Guerrero, S.; Park, J.; Xia, X.Nano letters
2013,
13 (7), 3420-3425.

Kavian, R.; Choi, S.-I.; Park, J.; Liu, T.; Peng, H.-C.; Lu, N.; Wang, J.; Kim, M. J.; Xia, Y.; Lee, S. W. Journal of Materials Chemistry A
2016,
4 (32), 12392-12397.

Gan, L.; Heggen, M.; Cui, C.; Strasser, P.ACS catalysis
2015,
6 (2), 692-695.

Figure 1
Bipolar Polymer Electrolyte Interfaces As Separators for High Performance Direct Borohydride Fuel Cells
Authors: Wang Zhongyang , Parrondo Javier , He Cheng , Sankarasubramanian Shrihari , Ramani Vijay K 
Published: February 2020

Direct borohydride fuel cells (DBFCs), operating with NaBH4 as a fuel and H2O2 as the oxidant have attracted a lot of attention due to their high theoretical cell voltages and tactical advantages, particularly for defense-related applications. DBFCs have a high energy density of 9.3 kWh kg-1 and specific capacity of 5.67 kAh kg-1 based on NaBH4 oxidation in alkaline media [1]. Using liquid hydrogen peroxide as the oxidant, the DBFC is a safe and attractive low temperature power source for unmanned underwater vehicles (UUVs) as they exhibit excellent energy and power density, are safe, given the high flash point of NaBH4, and do not release any gaseous effluents, enabling operation at neutral buoyancy[2]. One challenge for this system is the separation between the anolyte fuel (1.5M NaBH4 in 3M KOH) and catholyte oxidant streams (15% H2O2 in 1.5M H2SO4), while another is the high instability of NaBH4 in acidic or even neutral pH. Herein, a bipolar interface membrane electrode assembly is demonstrated for maintaining pH control of the anolyte and catholyte compartments of the fuel cell. The bipolar interface employed to separate anolyte and catholyte was based on an anion exchange membrane (AEM) interface in conjunction with a cation exchange membrane (Nafion®) separator. Studies of ion-containing block copolymers have provided clear evidence that the phase separation between hydrophilic and hydrophobic phases can produce materials with excellent ionic conductivity [3, 4]. The DBFC with the bipolar interfaces yielded a promising peak power density of 300 mW cm-2 in a 5-cm2 active area cell. Different operating conditions such as catalyst loading, operation temperature, flow rate and thickness of separator were investigated. The bipolar junction offers improved performance in the DBFC when compared with the use of a typical AEM or PEM configuration in the MEA.

References

[1] J. Milikić, G. Ćirić-Marjanović, S. Mentus, D.M.F. Santos, C.A.C. Sequeira, B. Šljukić, Electrochim. Acta, 213 (2016) 298-305.
[2] C.G. Arges, V. Prabhakaran, L. Wang, V. Ramani, Int. J. Hydrogen Energy, 39 (2014) 14312-14321.
[3] Y. Ye, S. Sharick, E.M. Davis, K.I. Winey, Y.A. Elabd, ACS Macro Letters, 2 (2013) 575-580.
[4] L. Sun, J. Guo, J. Zhou, Q. Xu, D. Chu, R. Chen, J. Power Sources, 202 (2012) 70-77.
Nickel Nanoparticles Decorating Graphite Flake Surface Using Planetary Ball Milling: Physical Characterization and Methanol Electrooxidation Investigation
Authors: Garcia-Basabe Yunier , Rodrigues da Cunha Rafael Otoniel Ribeiro , Salgado Jose Ricardo Cezar , Larrude Dunieskys Gonzalez , Sossmeier Kelly Daiane 
Published: February 2020

In recent years, several researches have been conducted in order to investigate the physical and chemical method for obtain the metallic nanoparticles, such as co-precipitation, hydrothermal, thermal decomposition of organometallic compounds, electrochemical, and ball milling method [1-4]. The particle size, shape and crystallinity depend on the selected synthesis method. In this sense the ball milling technique is one of the widely used to produce metallic nanoparticles, being the method feasible for large production [4].
A simple approach was proposed to obtain graphite surface decorated with nickel nanoparticles (Ni NPs) from dry ball milling process. Ni NPs were obtained after 40 h of high energy milling and 100, 200, 300 and 400 rpm ball rotation speeds. Both Ni NPs and graphite decorated samples were characterized by Scanning Transmission (STEM), Raman Spectroscopy, Scanning Electron Microscopy, X-ray diffraction pattern (XRD). The electrocatalytic activity of Ni/Graphite samples were evaluated from methanol oxidation in alkaline medium using electrochemical techniques.
Good agreement between STEM and XRD results can be found, reporting average diameter size of 4.9 nm and average crystallite size of 5.50 nm for Ni NPs. The methanol electrooxidation electrocatalytic activity was more efficient for Ni/Graphite with 100 rpm compared to Ni/Graphite others.
REFERENCES

M. Freire, T.S. Ribeiro, I.F. Vasconcelos, J.C. Denardin, E.B. Barros, M. Giuseppe, L. Carbone, S.E. Mazzetto, P.B.A. Fechine, MZnFe2O4 (M = Ni, Mn) cubic superparamagnetic nanoparticles obtained by hydrothermal synthesis, J. Nanopart. Res. 15 (2013) 1-12.

Alonso, P. Riente, J.A. Sirvent, M. Yus, Nickel nanoparticles in hydrogen-transfer reductions: Characterisation and nature of the catalyst, Appl. Catal. A 378 (2010) 42–51.

Aghazadeh, A.N. Golikand, M. Ghaemi, Synthesis, characterization, and electrochemical properties of ultrafine b-Ni(OH)2 nanoparticles, Int. J. Hydrogen Energy 36 (2011) 8674-8679.

F. de Carvalho, S.N. de Medeiros, M.A. Morales, A.L. Dantas, A.S. Carriço, Synthesis of magnetite nanoparticles by high energy ball milling Appl. Surf. Sci. 275 (2013) 84-87.
The Effect of Initial Chemical State of Copper Nanoparticles Towards C2 Products for Electrochemical CO2 Reduction
Authors: Jung Hyejin , Min Byoung Koun , Hwang Yun Jeong 
Published: February 2020

The electrocatalytic reduction of CO2 to value-added products with utilizing the renewable electricity is a promising alternative for using fossil fuels and an attractive solution for mitigating the constant rise in atmospheric CO2 emissions.
Among all kinds of metal catalysts, copper is the only one that has capability to produce considerable amounts of hydrocarbons and alcohols at a moment. However, the selectivity control towards products is a main challenge for using a copper as a catalyst.
In recent studies, oxide-derived copper has emerged as an efficient electrocatalyst candidate for better C-C coupling ability and lower overpotentials. Although the reason for this enhanced ability is still under debate, the residual oxygen or Cu+ in nanostructured subsurface region has been proposed as a critical factor to improve selectivity towards C2 products and in-situ analyses examined this suggestion.
Here, we synthesized copper nanoparticles (NPs) directly grown on carbon support by wet-chemically facile one-pot method. We prepared two kinds of Cu NPs with different morphology and chemical state by controlling the synthesis temperature. The one is Cu2O with cube shape and the other is Cu/CuOx with sphere shape, which are confirmed by TEM, XPS and Cu K-edge XANES analysis. The electrocatalytic CO2 reduction reaction (CO2 RR) was conducted in 0.1 M KHCO3 aqueous solution and the effect of initial chemical state of copper on C2H4 selectivity was investigated. We observed that C2H4 selectivity is highly improved when the initial chemical state of copper nanoparticles is Cu2O compared to Cu/CuOx with the faradaic efficiency is 55 % and 20 %, respectively at -1.05 V (vs. RHE). For the verification of the reason for improved activity, we conducted XANES experiment and TEM analysis in the middle of CO2 RR. We conclude that the subsurface oxygen enhance catalytic activity and stability for ethylene production.
Figure 1. TEM images of (A) cubic Cu2O/C and (B) sphere Cu/CuOx/C

Figure 1
Solar-to-Hydrogen Efficiency: Shining Light on Photoelectrochemical Device Performance
Authors: Young James L. , Döscher Henning , Geisz John F , Turner John A , Deutsch Todd G 
Published: February 2020

Direct photoelectrochemical (PEC) hydrogen production aims to provide a clean and cost-effective solar fuel. Solar-to-hydrogen (STH) conversion efficiency is central to evaluating and comparing research results, and it largely establishes the prospect for successfully introducing commercial solar water-splitting systems. Present measurement practices do not follow well-defined standards, and common methods potentially impact research results and their implications. We demonstrate underestimated influence factors and experimental strategies for improved accuracy[1].
Our focus is tandem devices that have the prospect for greater STH efficiency[2], but increased complexity that requires more careful consideration of characterization practices. We perform measurements on an advanced version of the classical GaInP/GaAs design[3] while considering (i) calibration and adjustment of the illumination light-source; (ii) confirmation of the consistency of results by incident photon-to-current efficiency (IPCE), and (iii) definition and confinement of the active area of the device.
We propose applying the following standards for future PEC performance reporting: (i) traceable disclosure of the illumination-source configuration (lamp, filters, optics, PEC configuration) and/or its measured spectral distribution; (ii) thorough device-area definition including confinement of the illumination area and avoidance of indirect light paths; (iii) complementary IPCE confirmation of the solar-generation potential; (iv) proper consideration of faradaic efficiency. We will also give a brief overview of the PEC measurements and capabilities available at NREL to support academic and industry research.
[1] H. Döscher, J. L. Young, J. F. Geisz, J. A. Turner, and T. G. Deutsch, “Solar to hydrogen efficiency: Shining light on phoelectrochemical device performance,” Energy Environ. Sci. 2015.
[2] H. Döscher, J. F. Geisz, T. G. Deutsch, and J. A. Turner, “Sunlight absorption in water – efficiency and design implications for photoelectrochemical devices,” Energy Environ. Sci. 2014.
[3] O. Khaselev and J. A. Turner, “A Monolithic Photovoltaic-Photoelectrochemical Device for Hydrogen Production via Water Splitting,” Science. 1998.
Eradication of Candida Albicans Biofilm By Electrochemical Scaffold Producing Hypochlorous Acid
Authors: Zmuda Hannah M. , Kiamco Mia Mae , Mohamed Abdelrhman , Patel Robin , Beyenal Haluk 
Published: February 2020

Biofilms are present in virtually all chronic wounds and contribute to the delay of wound healing. Biofilms are communities of bacterial and/or fungal cells embedded in an extracellular polymeric substance. Conventional treatment methods utilizing topical applications or systemic delivery of antibiotics are often inadequate because biofilms are inherently resistant to most of these approaches since the majority of antibiotics are active against metabolically-active, but not dormant, cells. The present study examines a new technology that can simultaneously eradicate biofilms on the wound surface and promote wound healing.
The electrochemical scaffold (e-scaffold) is a platform technology that allows controlled, continuous electrochemical production of low concentrations of biocides. The proposed novel e-scaffold consists of a three-electrode system, the working and counter electrodes are made of flexible carbon fabric, are accompanied by a Ag/AgCl reference electrode, controlled using a custom potentiostat. The e-scaffold works by electrochemically oxidizing chloride ions on the working electrode to chlorine gas when a constant potential of 1.5 VAg/AgCl is applied, and produces hypochlorous acid via chlorine dissolution. A phosphate buffer saline solution is added to the e-scaffold to provide chloride ions. While e-scaffold effectiveness in eradicating bacterial and antibiotic resistant bacterial biofilms was demonstrated in previous studies, its effectiveness against fungal biofilms has not been demonstrated. The goal of this work is to demonstrate the efficacy of the e-scaffold against in vitro
Candida albicans biofilm.
Fungal biofilms, such as C. albicans, differ from bacterial biofilms because fungal cells are eukaryotic cells and polymorphic, making fungal biofilms difficult to treat. After treating the C. albicans biofilm in an in vitro model with electrochemically produced hypochlorous acid using e-scaffold for 24 hours, the biofilm was completely eradicated. The results suggest that the electrochemical scaffold is a viable, new technology that can simultaneously eradicate antibiotic resistant fungal biofilms from the surfaces.
(Invited) Retrospective on Oxygen Reduction Electrocatalyst R&D Supported By the U.S. Department of Energy
Authors: Garland Nancy L. 
Published: February 2020

Fuel cells are highly efficient energy conversion devices; they can operate on fuels such as natural gas, methane, and methanol as well as hydrogen generated using diverse domestic resources. Fuel cells are efficient, scalable, and can be used in a variety of applications - from the transportation sector to the generation of primary and secondary power. The U.S. Department of Energy’s (DOE's) Hydrogen and Fuel Cell Program supports early-stage research and development leading to energy security and resiliency, paving the way to a strong domestic economy. Because reducing cost and increasing durability remain as the major challenges in the advancement of fuel cell technology, early-stage R&D includes improvements in performance and durability and lower cost catalysts as well as membrane electrode assemblies for fuel cells and electrolyzers.
This presentation will describe the development of oxygen reduction catalysts for fuel cells focusing on the tremendous achievements from Dr. Adzic of Brookhaven National Laboratory. His association with DOE's Office of Energy Efficiency and Renewable Energy began in 2003 with the introduction of Platinum Monolayer Electrocatalysts and was extended to the broader concept of core-shell catalysts. As just a single recent example of the promise of the catalysts, Dr. Adzic and his team recently found that nitriding core components, such as NiPd alloy, in core-shell electrocatalysts resulted in a 50% reduction in Pd content compared to extant Pt/Pd/C catalysts and enhanced overall stability and activity. As a whole, the core shell catalysts have captured the attention of the industry and beyond resulting in U.S. patents, some of which have been licensed to catalyst producers. Other research groups have adopted BNL's concept of core-shell catalysts as well as the use of gold for increasing durability in catalysts. Not surprisingly, R&D 100 and many other awards have followed.
Field Testing of Floating Microbial Fuel Cells and Energy Harvesting Related Power Systems
Authors: Cristiani Pierangela , Bonelli Paolo , Liberale Alessandro , Tucci Matteo , Papacchini Maddalena , Trasatti Stefano P. 
Published: February 2020

Microbial Fuel Cells (MFCs) are a promising technology to harvest energy from aquatic environments and act as sensing devices at the same time. Several prototypes of sediment MFCs have been tested in the past and more recently floating systems have been investigated as well, with encouraging results both in terms of energy harvesting and sensing. The challenge is now to scale up laboratory MFC designs for self-powering water quality sensors and implement these in real environments, where electricity sources may not be available. In this work, the performances of floating MFCs, suitably designed for aerobic and anaerobic water environments, were studied in long-term experiments. Several designs of flat and tubular cells were tested, using low-cost materials, such as plastic lunch boxes, and polystyrene or wood to keep the system afloat. Untreated carbon cloth, free of any chemical catalyst, was used for the electrodes. Flat MFCs were able to generate up to 15 mW/m2, depending on nutrient availability in the water. The electric performance of cathodes and anodes were differently correlated to chemical and physical water parameters (day/night cycle, chemical oxygen demand, total carbon content, nitrates and temperature among others). The Total Organic Carbon and Total Inorganic Carbon in the tank were continuously monitored with Sievers 820 Portable Total Organic Carbon Analyzer and compared to the current production of the cells.
Different types of power management systems had to be suitably designed, depending of the range of power produced by the MFC prototypes. A new generation of low-energy remote system (LORA) was integrated in an electronic circuit to harvest the power generated from MFCs and to transmit signals over long distance.
The experimentation was carried out in the wastewater plant site at Carimate (Figure 1), Como (Italy) and in the pool of the city garden “Orto Botanico Città Studi” at Milan (Italy).

Figure 1