bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Advanced Components Development for Electrochemical Ammonia Synthesis
Authors: Xu Hui , Zhao Shuai , Biddy Mary J. , Yan Yushan , Wu Gang 
Published: February 2020

Ammonia is an essential industrial chemical for agricultural fertilizer, medical intermediates, and energy storage. For fuel cell electric vehicle applications, it can be used as a fuel directly or as a means of hydrogen storage due to its high energy density in the liquid state. Conventional ammonia production using Haber-Bosch processes require high pressure and temperature, which is energy intensive. In addition, approximately 1.9 tons of carbon dioxide is released per ton of ammonia produced, because fossil fuels are used as the energy source in the ammonia industry. Meanwhile, renewable energy sources like solar and wind have significantly penetrated into the energy market in the past decade. During off-peak times, a large portion of this renewable energy cannot be utilized and an economically viable technology has to be used to store this surplus, “stranded” energy. The strong need to store off-peak renewable energy provides an unprecedented opportunity to utilize electrochemically synthesized ammonia as a means of accumulating hydrogen equivalents and stranded energy.
Our work aims to design and implement advanced components (e.g. catalyst and membrane) to transform electrochemical synthesis of ammonia (EAS) 1-2 and to integrate this process with off-peak renewable energy. The reactants are nitrogen and water that are immediately available and abundant. Novel metal oxide and metal nitride catalysts for the nitrogen reduction reaction (NRR) have been designed and synthesized, which may boost the ammonia production rate by at least an order of magnitude; the developed catalyst can also effectively suppress competing hydrogen evolution reaction. Second, high temperature anion exchange polymer membrane and composite ceramics electrolyte have been explored to further enhance process stability and ammonia production rate; they also enable the EAS at a wide temperature range, from 80 ℃ to 350 ℃. Techno-economic analysis (TEA) of the EAS system integrated with renewable energy will be analyzed to evaluate the cost feasibility. Faradic efficiency and overall electrical efficiency in the context of capital cost and operations cost will also evaluated.

Acknowledgement: ARPA-E REFUL Program under award # DE_AR000814
Reference:

Marnellos, G., and M. Stoukides, “Ammonia synthesis at atmospheric pressure,” Science, 282(2), 98-100 (1998).

Licht, S, Cui, B., Wang, B., Li, F-F, Lau, J., and Liu, S., “Ammonia syhthesis by N2 and steam electrolysis in molten hydroxide suspensions of nanoscale Fe2O3”, Science, 345, 637-640 (2014)
Differential Pulse Voltammetry of Nitrobenzene
Authors: Haque Inam ul 
Published: February 2020

Removal of nitrobenzene from water is of current interest due to its toxicity (1) as a mutagen and carcinogen. Water sample with initial known concentration of nitrobenzene (4mM) was taken and treated with adsorbent: spent tea leaves (2). After treatment with adsorbent nitrobenzene was analyzed using such electrochemical techniques (3) as differential pulse, Figure 1, and square wave voltammetry (curve not shown) to obtain a calibration curve for quantitative estimation of nitrobenzene.
Cyclic voltammetry was employed for preliminary work (4). A calculated amount of cetyltrimethylammonium bromide (CTAB) was added to a specific volume of all nitrobenzene solutions as the supporting electrolyte. All analyses were carried out in 0.1 M aqueous CTAB at a platinum cathode using EG&G VersaStat II.
This study shows that spent tea leaves can be effectively used for the removal of nitrobenzene from aqueous solutions. A substantial decrease in the concentration of nitrobenzene was observed after treating 100 mL of 4mM nitrobenzene solution with different weighed amounts of adsorbent (spent tea leaves) when a contact time of one hour was allowed, Figure 1.
References
(1) A. Hartwig, The MAK-Collection for Occupational Health and Safety, pp.1473-1544 (2017)
DOI: 10.1002/3527600418.mb33341e5917
(2) E. Heraldy, R. R. Osa and V. Suryanti, AIP Conference Proceedings, 1710, 030025 (2016)
(3) S. Manivannan, J. Jeong, D.-K. Kang, and K. Kim, Electroanalysis (2017) DOI:10.1002/elan.201700451
(4) I. U. Haque, AASCIT Journal of Materials (2017)

Figure 1
Metal- and Reagent-Free Anodic Dehydrogenative Coupling Reactions
Authors: Waldvogel Siegfried R. 
Published: February 2020

The dehydrogenative cross-coupling is a hot topic of contemporary organic synthesis. The anodic cross-coupling reaction of aromatic substrates is established without necessity of leaving functionalities or mediating catalyst. Employment of electric current as terminal oxidant is reagent-free and consequently, avoids the generation of reagent waste since only electrons are flowing. The method can be conducted in an undivided cell, is suitable for scale-up and inherently safe. Therefore, it is highly attractive for a sustainable synthesis. The key for this electroorganic synthesis is the use of 1,1,1,3,3,3-hexafluoroisopropanol as electrolyte component.[1] The high hydrogen-bonding donor capability allows a decoupling of oxidation potential from the nucleophilicity.[2] This solvent effect can be controlled by the addition of methanol or water.[3] By this method we were able to make in almost exclusive selectivity ortho-meta coupled 2,3’-biphenols,[4] non-symmetric 2,2-biphenols,[5] and phenol-arene cross-coupling products.[6]

References:
[1] A. Kirste, M. Nieger, I. M. Malkowsky, F. Stecker, A. Fischer, S. R. Waldvogel, Ortho-selective Phenol coupling reaction by Anodic Treatment on Boron-doped Diamond electrode using Fluorinated Alcohols, Chem. Eur. J. 15 (2009) 2273.
[2] B. Elsler, A. Wiebe, D. Schollmeyer, K. M. Dyballa, R. Franke, S. R. Waldvogel, Source of Selectivity in Oxidative Cross-Coupling of Aryls by Solvent Effect of 1,1,1,3,3,3-Hexafluoropropan-2-ol, Chem. – Eur. J. 21 (2015) 12321
[3] A. Kirste, B. Elsler, G. Schnakenburg, S. R. Waldvogel, Efficient anodic and direct phenol-arene C,C cross-coupling – the benign role of water or methanol, J. Am. Chem. Soc. 134 (2012) 3571.
[4] A. Kirste, G. Schnakenburg, S. R. Waldvogel, Anodic Coupling of Guaiacol Derivatives on Boron-doped Diamond Electrodes, Org. Lett. 13 (2011) 3126.
[5] B. Elsler, D. Schollmeyer, K. M. Dyballa, R. Franke, S. R. Waldvogel, Metal- and Reagent-Free Highly Selective Anodic Cross-Coupling Reaction of Phenols, Angew. Chem. Int. Ed. 53, (2014) 5210.
[6] A. Kirste, G. Schnakenburg, F. Stecker, A. Fischer, S. R. Waldvogel, Anodic phenol arene cross-coupling reaction on boron-doped diamond electrodes, Angew. Chem. Int. Ed. 49 (2010) 971.

Figure 1
Miniature Biological Fuel Cells for Sensing Applications
Authors: Di Lorenzo Mirella 
Published: February 2020

Biological fuel cells (BFCs) are a type of fuel cell in which enzymes, pure or inside whole cells, are used as catalysts. BFCs presents several advantages over abiotic fuel cells, such as low operational temperature and pressure and cost-effectiveness. On the other hand, key challenges of BFCs are mainly associated to low power densities and, in the case of pure enzymes, limited half-life.
Widely explored as a technology for wastewater treatment and simultaneous electricity generation, BFCs have enormous potential as self-powered sensors, which is currently gathering increasing attention.
This talk will provide an overview of our current research into miniature BFCs for sensing applications for either environmental monitoring or healthcare. To improve the sensing potential of BFCs we focus on: device design, electrode morphology and low-cost materials. Miniaturisation can lead to highly sensitive devices. The large electrode surface area to volume ratio in small-scale BFCs, in fact, increases the active surface area for reaction, thus leading to high fuel consumption efficiency, while the short electron spacing minimises the internal Ohmic losses. Micro-structured electrodes have demonstrated to lead to high current densities, and therefore greater baseline signal and detection limits of the sensor. Finally, with the aim of generating cost-effective devices, we explore the use of low cost materials, such as paper and biomass-derived oxygen reduction catalysts as a green and cheap alternative to platinum at the cathode.
Electroorganic Oxidation of Pyridones
Authors: Rodene Dylan Daniel , Gade Narendar R , Jee Joann , Roper Thomas D , Gupta Ram B. 
Published: February 2020

Electroorganic synthesis can be utilized as a green alternative in complex organic synthesis reactions for pharmaceutical compounds, mitigating or eliminating complex stoichiometric oxidants during organic synthesis. An electrochemical oxidation reaction can make a synthetic transformation more cost effective and more efficient when compared to traditional oxidation processes. Recently, literature has indicated that in waste water treatment applications, benzene and phenols are completely oxidized, resulting in CO2 formation, but interestingly also resulting in some partial oxidation products of quinones and catechols. Following a similar scheme to intentionally produce partial electrochemical oxidation products and oxidation intermediates can yield interesting new chemistries.
In this work, we will focus on heterocyclic electrochemistry and their partial oxidations specifically for pyridones. Pyridones and pyridines are considered for their possible use in biological reactions or in mimicking bioorganic processes. Various electrochemical oxidations with pyridones as an organic substrate are being explored, specifically N-alkyl pyridones.
Herein, focus will be on examining various cyclic voltammograms for different supporting electrolyte systems while comparing one and two electrochemical cell systems. Reaction rates and possible electrochemical mechanisms will be developed similarly to literature on electrochemical sensors. Furthermore, the electrochemical analysis will be derived and compared to the reaction products characterized by LC-MS.
Dynamic Nanostructuring as a Tool to Fabricate High Performance Copper Based Hydrogen Evolution Electrocatalyst
Authors: Manna Liberato , Shinde Dipak , De Trizio Luca 
Published: February 2020

Electrochemical production of hydrogen using electricity obtained from renewable sources such as Solar and wind represents an attractive avenue for clean and sustainable energy production and storage. Herein we report a low cost, highly active and stable copper based catalyst for hydrogen evolution reaction (HER) fabricated by chemical solution deposition. The catalyst exhibits self-optimizing behavior under hydrogen evolution conditions. Structural and morphological studies performed on pristine and self-optimized catalyst indicates that it undergoes nanostructuring from porous nanoplates to foam-like interconnected nanowires composed of ultra-small Cuo nanoparticles (2~3 nm in size) as shown in figure 1. Electrochemical impedance spectroscopy performed after various CV cycles suggests that there is substantial reduction in charge transfer resistance which is associated with large increase in effective double layer capacitance of the catalyst. This agrees well with the morphological analysis, wherein, nanostructuring was observed after CV cycling. A dissolution-reprecipitation based mechanism is suggested to explain the observed morphological changes. The proposed catalyst exhibits hydrogen evolution current of 10 mA/cm2 at an overpotential of 105 mV. The detailed results will be presented in the meeting.
Figure 1. a) TEM image of Cu based catalyst after cycling, b) Linear sweep voltammograms of various electrodes obtained at a sweep rate of 10 mV/S

Figure 1
Photoelectrochemical Methanol Oxidation on TiN Nanoparticles Supported on TiO2
Authors: Baturina Olga A , Epshteyn Albert , Simpkins Blake 
Published: February 2020

Titanium nitride (TiN) is a metallic nitride that has optical properties similar to gold, thus enabling it to support plasmonic resonances in visible region [1, 2]. It has been considered as an attractive alternative to noble plasmonic metals due to low cost, high mechanical and thermal stability and flexibility in terms of material design [2]. While the plasmon-driven photocatalytic reactions of gold nanoparticles have been demonstrated, very little work has been reported on photocatalytic properties of supported TiN nanoparticles. It has been shown recently [3] that cubic 50 nm TiN nanoparticles supported on TiO2 nanowires provide greater photocurrent enhancement for photoelectrochemical water splitting compared to spherical Au nanoparticles. Increased hot carrier generation by the TiN nanoparticles followed by more efficient carrier collection by TiO2 was cited as the cause.
Here, plasmonic and catalytic properties of a TiN/TiO2 nanoparticle composite are probed in methanol oxidation reaction. The effects of variables such as plasmonic nanoparticle loading and particle size on the efficiency of visible to chemical energy conversion are investigated and discussed.
TiO2-supported TiN photocatalysts were made from commercial 20 and 50 nm TiN (PlasmaChem), and TiO2 nanoparticles (Degussa) by wet chemistry methods. X-Ray Photoelectron Spectroscopy and high resolution transmission electron microscopy were used for the analysis of the catalysts’ surface composition and morphology, respectively. Electrochemical experiments were conducted in a three-electrode photoelectrochemical cell. The TiN/TiO2 films on FTO-coated glass served as the working electrodes (WEs), while platinum foil and Ag/AgCl in 3 M NaCl (BioLogic, Inc) were used as counter and reference electrodes, respectively. LED lights (ThorLabs) were used as a light source.
References
[1] G.V. Naik, J.L. Schroeder, X. Ni, A.V. Kildishev, T.D. Sands, A. Boltasseva, Optical Materials Express, 2 (2012) 478.
[2] U. Guler, A. Boltasseva, V.M. Shalaev, Science, 344 (2014) 263.
[3] A. Naldoni, U. Guler, Z.X. Wang, M. Marelli, F. Malara, X.G. Meng, L.V. Besteiro, A.O. Govorov, A.V. Kildishev, A. Boltasseva, V.M. Shalaev, Advanced Optical Materials, 5 (2017).
Semi-Integral Electroanalysis of the Electrochemistry of Tris(2,2`-bipyridine) Complexes
Authors: Cabral Diogo Moulin , MacFarlane Douglas R 
Published: February 2020

The 2,2`-bipyridine (bpy) ligand is one of the most widely used in coordination chemistry. It was first synthesized at the end of the 19th century, with the iron(II) tris(bpy) being the first complex of this ligand ever observed1. Over the years a diversity of metals complexed with bpy have been synthesized and extensively studied, and recently some applications of these complexes have been proposed, e.g. the use of iron (II) and nickel (II) tris(bpy) complexes for non-aqueous electrolytes of batteries2 and the use of cobalt (II) tris(bpy) for thermo electrochemical cells3. Also, currently there is a growing interest in using ionic liquids (ILs) for electrochemical applications, because these compounds, broadly defined as salts that are liquid at or close to room temperature, usually present some interesting properties, such as low volatility, non-flammability and intrinsic ionic conductivity. The semi-integral electroanalysis is a powerful method for investigating the kinetics of redox reactions and determining the diffusion coefficients4 and was used to aid the interpretation of the electrochemical behaviour of tris(bpy) complexes.
The purpose of this work was to study the electrochemistry of the tris(bpy) complexes of cobalt (II)5, nickel (II) and iron (II)6 in ILs and organic solvents, thus contributing to the understanding of how these compounds behave in these media. Four ILs (two having the imidazolium cation and two the pyrrolidinium cation) and three organic solvents were used and the basic electrochemical properties of these complexes were investigated, including the redox potentials and the chemical and electrochemical reversibility of the redox reactions, as well as the kinetics of the oxidation reactions. The semi-integral electroanalysis was used for determining diffusion coefficients and for a qualitative analysis of the reversibility of the redox reactions.

E. C. Constable, in Adv. Inorg. Chem., ed. A. G. Sykes, Academic Press, 1989, vol. Volume 34, pp. 1-63.

J. Mun, M.-J. Lee, J.-W. Park, D.-J. Oh, D.-Y. Lee and S.-G. Doo, Electrochem. Solid-State Lett., 2012, 15, A80-A82.

M. A. Lazar, D. Al-Masri, D. R. MacFarlane and J. M. Pringle, PCCP, 2016, 18, 1404-1410.

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D. Cabral, P. C. Howlett, J. M. Pringle, X. Zhang and D. MacFarlane, Electrochim. Acta, 2015, 180, 419-426.

D. M. Cabral, P. C. Howlett and D. R. MacFarlane, Electrochim. Acta, 2016, 220, 347-353.
(Invited) Advancements in Ethanol Oxidation Reaction Mechanisms with Alkaline Direct Ethanol Fuel Cells
Authors: Chen Rongrong , Guo Junsong 
Published: February 2020

Since the development of alkaline anion exchange membranes (AAEMs), Direct Ethanol Fuel Cell (DEFC) has gained significant research interest as an alternative to high-cost Direct Methanol Fuel Cell (DMFC) based on proton exchange membranes (PEMs). There are several advantages to utilization of ethanol fuel compared to methanol fuel, including: 1) existing infrastructures for ethanol production from various biomasses, liquid fuel storage, and transportation, 2) high specific energy density, and 3) decreased chemical toxicity. Furthermore, alkaline DEFCs have several advantages over PEM DMFCs, including: 1) improved kinetics of anodic ethanol oxidation reactions (EOR) and cathodic oxygen reduction reactions (ORR) in alkaline media; and 2) a wide range of catalyst materials in addition to Pt are stable in alkaline media and can be chosen as the catalysts for either EOR or ORR. Consequently, ADEFCs that do not require expensive Pt catalysts become feasible.
However, the poor kinetics of ethanol oxidation reaction (EOR) and the need to break C-C bonds to complete oxidation of ethanol to CO2 have been major challenges for the development of DEFCs. Precious metals such as Pt and Pd are commonly used as primary catalysts for EOR in ADEFCs. In order to increase catalyst performance, Pt and Pd are usually combined with other transition metals, such as Ru, Sn, Pb, Au, Ni, Ag, Cu or Bi, as alloys, deposits, or ad-atoms. In our previous work, the electrocatalytic activity of PdxRuy/C catalysts for the EOR was demonstrated to be much better than that of Pd/C in ADEFCs. The transition metal Ru in RuxPdy was thought to enhance ethanol oxidation with the assistance of hydroxyl groups on the catalyst surface formed at lower potentials. However the oxidation of ethanol in alkaline media is very complex and involves many types of intermediates, such as C1 species (most likely COad and CHx,ad), OHad, CH3COad and other forms of acetaldehyde in alkaline media. The roles of Ru in PdxRuy/C and durability of PdRu/C catalysts for ethanol oxidation have not been elucidated and require further investigation.
In our recent work, we conducted comprehensive studies of EOR on several Pt-based and Pd-based catalysts by not only using half-cell testing, such as cyclic voltammetry (CV) and chronoamperometry (CA), but also fuel cell testing under various test conditions. An accelerated test was established to evaluate the stability of anode catalysts. In situ FTIR experiments were carried out to determine EOR intermediate and final products on these various catalyst systems. These comprehensive studies provide novel insights regarding the roles of second transition metal (Ru, Pb or Cu) in Pd or Pt catalyst for EOR in alkaline media, unveil the causes of the performance degradation of fuel cells with traditional catalysts, and indicate that catalysts with good initial performances are not essential for being appropriate for ADEFC applications.
Electrooxidation of Propylene to Acrolein
Authors: Seger Brian , Winiwarter Anna , Stephens Ifan , Chorkendorff Ib 
Published: February 2020

Short chain alkanes and alkenes (C1-4) typically have little economic value and are difficult to transport since they are gases. Because of this, these hydrocarbons are of so low value that they are often flared during extraction of oil.1 This talk investigates electrochemically partially oxidizing these materials to high-value liquid products, thus increasing both the value and ease in transportation. If the oxidation is cathodic enough (< ~ +0.9 V vs. RHE) this can be combined with a standard oxygen reduction reaction cathode in a PEM fuel cell type approach to produce a device that does not consume electrical power, but actually has the potential to produce a small amount of power.2

Specifically this talk focuses on partial electrochemical oxidation of propylene to a variety of high value products such as acrolein, propylene oxide, propylene glycol, and acrylic acid and low value products such as CO2, and acetic acid. Using a Pd catalyst, we analyse the effects of pre-treatment, potential, pH and other factors in optimizing high value products while minimizing low value products. As shown below, one of the most promising findings is a high degree of acrolein selectivity at 0.9 V vs RHE in acidic solutions.
The figure below shows that we can achieve stable electrochemical oxidation of propylene for 1 hour and produce acrolein with a selectivity of near 80%.

Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B. T.; Ghosh, T.; Pack, D. W.; Erwin, E. H.; Zhizhin, M., A Fifteen Year Record of Global Natural Gas Flaring Derived from Satellite Data. Energies 2009, 2 (3), 595-622.

Yamanaka, I., Active control of catalysis and product selectivity by a fuel cell system. Research on Chemical Intermediates 2006, 32 (3-4), 373-38

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(Invited) Computational Insights to the Charge Transfer Reaction at the Complex Li/SEI/Electrolyte Interface
Authors: Qi Yue , Li Yunsong 
Published: February 2020

The performance of Li-ion batteries (LIB) is highly dependent on the electrochemical reactions occurring at the Solid Electrolyte Interphase (SEI). However, its nanometric scale thickness combined with its complex structure makes the SEI remains “the most important but the least understood in LIB”. Simulations can provide critical insights to the electrochemical reactions at the electrode/SEI/electrolyte interface. Density Function Theory (DFT) and Density Functional Tight Binding (DFTB) methods were used to model the charge transfer reaction at a Li/Li2CO3/liquid Ethylene carbonate (EC) electrolyte interface. In this study, we first developed a new set of DFTB parameters for Li-X (X=Li, H, C, O) interactions by fitting and calibrating with various DFT calculations. Then, the lithiation and delithiaiotn processes were simulated.
The simulation clearly showed four layers Li2CO3 can effectively protect the Li electrode surface within the simulation time. During de-lithiation, it was energetically favorable to form a void at the Li/Li2CO3 interface. The lithiation process was simulated as three steps: Li+ desolvation at the SEI/Electrolyte interface, Li+ diffusion through the Li2CO3 layer, and annihilation of e- and Li+ at the Li surface. The simulation clearly demonstrated the charge transfer reaction of Li+ + e- -> Li0 occurs at the Li/Li2CO3 interface or beneath the SEI layer. The energy profile of this reaction was simulated under different applied voltage. It was found that the experimentally defined zero voltage of Li+/Li0 corresponds to a negatively charged Li metal surface at a charge density of ~ 1e/nm2. When the electron density is larger than this (more negative potential), Li plating occurs; while when the electron density is lower than this (more positive potential), Li stripping occurs. The excess electrons on the Li surface will trigger more electrolyte decomposition and Li-dendrite formation when SEI fractures.