bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Influence of the Binder on the Investigation of Electrocatalysts for Oxygen Evolution Reaction in Alkaline Water Electrolysis
Authors: Narangoda Praveen Vidusha , Neugebauer Sebastian , Schloegl Robert , Mechler Anna Katharina 
Published: February 2020

Rotating disc electrode (RDE) technique is a useful and commonly accepted technique for the performance evaluation of electrocatalysts for the oxygen- reduction (ORR) and evolution (OER) reactions.[
1] To characterize new catalysts, composite thin film electrodes are casted on RDE tips (TF-RDE) where polymers are typically utilized as binders to immobilize the powder electrocatalysts onto the substrate.[
1b] Literature surveys show Nafion® as a feasible binder for the investigation of alkaline OER catalysts. However, Nafion® was developed for application in PEM fuel cells that rely on the transport of protons rather than anions.[
2] To our best understanding, there is no systematic investigation on the influence of polymer binders in alkaline OER. As shown in Figure 1, Nafion® can affect the OER performance, especially described by the phenomenon of gas bubble retention on the electrode surface during chronopotentiometry (Figure 1C) and a significant influence of the amount of binder added to the thin film.[
3]

Here we will present a TF-RDE study of a benchmark catalyst (Ni, Co- Oxide, Sigma Aldrich) on glassy carbon and gold substrates, prepared with commercially available binders (Nafion®, Aquivion®, PTFE and Fumion®). We used a standardized preparation and measurement protocol to ensure comparability and reproducibility. The results show a significant influence of the choice of binder on the measured OER performance. These differences are discussed with respect to the binder properties in terms of hydrophilicity or functional groups, as well as their corrosion behavior under OER conditions.
[1] a) K. J. J. Mayrhofer, D. Strmcnik, B. B. Blizanac, V. Stamenkovic, M. Arenz, N. M. Markovic, Electrochimica Acta
2008, 53, 3181-3188; b) J. Suntivich, H. A. Gasteiger, N. Yabuuchi, Y. Shao-Horn, Journal of The Electrochemical Society
2010, 157, B1263-B1268; c) T. Reier, M. Oezaslan, P. Strasser, ACS Catalysis
2012, 2, 1765-1772.
[2] a) M. Paidar, K. Vazac, M. Roubalik, K. Bouzek, in Hydrogen Days, Prague, Czech Republic, 2015; b) S. Jung, C. C. L. McCrory, I. M. Ferrer, J. C. Peters, T. F. Jaramillo, Journal of Materials Chemistry A
2016, 4, 3068-3076.
[3] K. Zeng, D. Zhang, Progress in Energy and Combustion Science
2010, 36, 307-326.

Figure 1
(Europe Section Allessandro Volta Medal) From Nanobiosensors to Scanning Bipolar Electrochemistry
Authors: Schuhmann Wolfgang 
Published: February 2020

Measurement of physiological relevant molecules in and at individual cells with minimal disturbance of the cellular function is a key challenge in single-cell analysis. Ad­vantages of nanoscale electrochemical probes include their high spatial and tempo­ral resolution as well as a low substrate consumption. Carbon nanoelectrodes (CNEs) with a tunable radius between a few and several hundreds of nanometres can be fabricated by pyrolytic decomposition of alkane gas in glass nanopipettes. Their needle-type shape and small size enable electro­chemical measurements inside of single living cells. Two potential applications of CNEs namely for the design of nanometer-sized amperometric biosensors, and as the basis for gate-modulated reduced graphene oxide based transistors are presented.
However, the probability that a nanosensor is positioned close to a release site is tiny. Hence, we propose to combine scanning electrochemical microscopy (SECM) with bipolar electrochemistry (BPE) as a new approach to image heterogeneous electrochemical surface processes. The core of the system is a closed bipolar electrochemistry configuration comprising as the bipolar electrode (BPE) a microelectrode as SECM tip (cathodic pole of the BPE) connected with a microelectrode tip (anodic pole of the BPE) in the second half cell. Reduction processes enabled by a suitably applied feeder electrode voltage difference at the SECM tip in the sample generation/tip collection mode are transduced into an optical read-out e.g. electrochemiluminescence at the other pole which is visualized with a high sensitive CCD camera. Evidently, this configuration can be extended to multi-barrel SECM tips thus being able to simultaneously visualize the release of compounds at multiple locations while positioning the multi-barrel microelectrode above a release site of interest.

Acknowledgement
: All coworkers who have contributed to this research are acknowledged namely Jan Clausmeyer, Vera Eßmann, Carla Santana Santos, Tsvetan Tarnec, Thomas Erichsen, Miriam Marquitan, Patrick Wilde, Thomas Quast, Corina Andronescu, Federica Mariani. The author is grateful to the project "Graphtivity" funded in the framework of the FLAG-ERA Joint Transnational Call (JTC) 2015 (Graphene Flagship) and the Deutsche Forschung­gemeinschaft in the framework of the cluster of excellence RESOLV (EXc1069).
Spectroelectrochemical Detection of Pharmaceutical Compounds Using Carbon Screen Printed Electrodes
Authors: Fanjul Bolado Pablo , González García María Begoña , Junquera Pérez Alejandro , Hernández Santos David 
Published: February 2020

Several analytical methods have been published concerning the determination of active pharmaceutical ingredients (APIs) in drug formulations or in environmental samples. The most commonly used are chromatographic techniques but these methods are time consuming, expensive, require complicated preconcentration processes and need sophisticated instruments. On the other hand, electrochemical methods present the advantage of high simplicity, high sensitivity, good stability and low cost. These instruments can also be portable, which is particularly suitable for on-site monitoring of pharmaceuticals in field analysis.
In the present work, Carbamazepine,
Ibuprofen, Clarithromycin, Naratriptan, Dopamine and Acetaminophen have been determined using different electrochemical techniques at screen printed electrodes (SPE). The spectroelectrochemical behavior of the voltammetric response of some of these APIs allows the selective detection of these compounds despite their similar oxidation potentials on SPEs. The analysis was carried out by simultaneously performing an electrochemical and an optical experiment, the corresponding voltabsorptograms obtained are presented, showing the correlation between the derivative voltabsorptograms at the maximum of absorbances and the electrochemical curve.
This work is supported by Innovec`EAU (SOE1/P1/F0173) project from the Interreg Sudoe 2014-2020 program funding by European Regional Development Funds
Physicochemical and Electrochemical Properties of FSA-Based Ionic Liquid Electrolytes for K-Ion Batteries
Authors: Yamamoto Takayuki , Matsumoto Kazuhiko , Hagiwara Rika , Nohira Toshiyuki 
Published: February 2020

Ionic liquids (ILs) are good candidates as electrolytes for electrical energy storage (EES) devices due to their high safety and superior physicochemical and electrochemical properties. Although Li-ion batteries (LIBs) are good candidates for EES and many types of IL electrolytes for LIBs were already reported [1-3], the limited amount of lithium and cobalt resources may lead to the unstable supply of LIBs in the future. Thus, several groups including us developed IL electrolytes for Na-ion batteries (NIBs) utilizing low-cost and ubiquitous resources of sodium and iron [4-8]. However, the standard potential of Na+/Na redox couple is lower than that of Li+/Li redox couple, which reduces the energy densities of batteries [9].
Under these circumstances, we have focused on K-ion batteries (KIBs) and developed new IL electrolytes containing alkyl-pyrrolidinium and -imidazolium cations. For example, in the K[FSA]-[C3C1pyrr][FSA] (C3C1pyrr+ = N-methyl-N-propylpyrrolidinium) binary system [10], a mixed melt at x(K[FSA]) = 0.20 (molar fraction) shows a reasonably high ionic conductivity of 4.8 mS cm−1 and a wide electrochemical window over 5 V at 298 K. The electrochemical windows of M[FSA]-[C3C1pyrr][FSA] (M = K, Na, Li) are compared by cyclic voltammetry. As the result, the K-ion system shows a wider electrochemical window than Na-ion and Li-ion systems due to negative potential of the K+/K redox couple, which implies the feasibility of KIBs possessing higher energy densities.

Acknowledgments

This study was partly supported by MEXT program "Elements Strategy Initiative to Form Core Research Center" (since 2012; MEXT: Ministry of Education Culture, Sports, Science and Technology, Japan), and a research grant from Kansai Research Foundation for Technology Promotion, Japan.

References

[1] H. Matsumoto et al., J. Power Sources, 160 (2006) 1308-1313.
[2] M. Ishikawa et al., J. Power Sources, 162 (2006) 658-662.
[3] A. Guerfi et al., J. Power Sources, 175 (2008) 866-873.
[4] S.A.M. Noor et al., Electrochim. Acta, 114 (2013) 766-771.
[5] D. Monti et al., J. Power Sources, 245 (2014) 630-636.
[6] L.G. Chagas et al., J. Power Sources, 247 (2014) 377-383.
[7] C. Ding et al., J. Power Sources, 238 (2013) 296-300.
[8] K. Matsumoto et al., J. Power Sources, 265 (2014) 36-39.
[9] N. Yabuuchi et al., Chem. Rev., 114 (2014) 11636-11682.
[10] T. Yamamoto et al., J. Phys. Chem. C, 121 (2017) 18450-18458.
Formation of Rare Earth Phosphates in the Melts Based on NaCl–KCl Equimolar Mixture
Authors: Volkovich Vladimir A. , Ivanov Alexander B. , Chukin Andrey V. , Sukhikh Vladislav V. , Griffiths Trevor R. 
Published: February 2020

Phosphate precipitation in molten chlorides is considered as a possible method for removing rare earth and alkaline earth fission product elements from technological melts at a final stage of pyrochemical reprocessing of spent nuclear fuels. Phosphates can be incorporated into a glass matrix in a high level waste vitrification process in preparation for a long term storage or disposal. There are a number of studies considering the formation of rare earth phosphates in the melts of technological interest, i.e. LiCl–KCl, NaCl–KCl, and NaCl–CsCl mixtures, but some uncertainty still remains concerning the conditions when different types of phosphates are formed. While the reaction in LiCl–KCl melts always produces normal orthophosphates (REPO4), double alkali metal-rare earth phosphates, e.g. M3RE(PO4)2 and M3RE2(PO4)3, can be formed in the melts not containing LiCl. The aim of the present study was investigating the effect of the initial phosphate-to-rare earth mole ratio on the outcome of the reaction.
The experiments were performed in the melts based on the equimolar mixture of sodium and potassium chlorides at 750 oC. The rare earth elements included Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu (heavier lanthanides not representing fission products were included for completeness). Sodium orthophosphate was used as a source of PO4
3– ions and the initial PO3
3– : RE3+ mole ratio was varied from 0.3–0.5 to 10. Formation of the phosphates was studied in the melts containing individual rare earth elements as well as a mixture of rare earths in the proportion simulating their abundance in the thermal neutron reactor spent fuel.
The experiments were performed under static conditions and the parameters analyzed included degree of RE precipitation, phase composition of the precipitate and size of particles in the solid phase. Analysis of the experimental results showed that at PO3
3– : RE3+ mole ratios below five only normal REPO4 phosphates were formed, while at the ratios above 8 double Na3RE(PO4)2 and/or K3RE(PO4)2 double phosphates were produced. Particle size of the rare earth phosphates varied from 0.1 to hundredths of microns and increasing the initial PO3
3– : RE3+ mole ratio resulted in increasing particle size. Complete conversion of RECl3 to phosphate required 2–5 times molar excess of the phosphate to the rare earth element.
Quantum-Chemical Study of the Titanium Complexes Stability in the Model System M2+ [Ti(3)F6]3-+12MCl2
Authors: Stulov Yuriy V. , Kremenetsky Vyacheslav G. , Kuznetsov Sergey A. 
Published: February 2020

In our previous works, a basic approach is to calculate the parameters of model systems containing an anionic complex with an outer sphere (OS) cationic shell. For similar systems nM+⋅[NbF7], nM+⋅[CrCl6] (n = 1 – nmax) and others (system I), it has been demonstrated that the most thermodynamically stable compositions have some intermediate number of OS cations n < n
max, where n
max is the maximal number of OS cations held by a given complex. In another our papers, an approach was proposed for estimating the stability of particles with different composition of the second coordination sphere of complexes in more complex model systems –M+
3Cr(3)Cl6+18MCl and M2+Ti(4)F6+12MCl2, where M2+ - Mg, Ca, Sr, Ba (system II).
The aim of this study is the quantum-chemical substantiation of the existence stable particles in alkali halide melts of formed by a titanium halide complex and an OS cationic shell of a certain composition in a model system M2+∙[Ti(3)F6]3-+12MCl2.
The geometry optimization of structures was performed with the Firefly program package, partially based on the source code of the GAMESS(US) program, by the density functional theory DFT/UHF method with the use of the B3LYP hybrid functional. For the F and Cl atom quasi-relativistic basis set Stuttgart RLC ECP was used; for Ti, Ca, Sr and Ba – Stuttgart RSC 1997 ECP basis set and for Mg – CRENBL ECP. In all cases, the search for the optimized geometry was accompanied by control calculation of vibrational frequencies, and, thus, all the data reported correspond to true minimum of the potential energy surface (there are no imaginary frequencies).
Different from system type I, in the system II it was possible direct calculation of the interaction energy between particle and rest part of the model system. If the interaction energy between the OS shell and titanium complexes exceeds the energy of its interaction with the rest environment, there are presence in the system of such dynamic equilibrium, which ensures the existence of sufficiently stable complex particles of a certain OS composition.
The analysis of interactions in systems I and II on the example of Ti(3) complexes showed that there are discrepancies between the composition of the most stable complex particles in these systems. Allowance for the interaction of the particle "complex plus OS shell" with the surrounding ions gives a much more accurate estimate of the composition of the electroactive particles. Thus, using the model system of nM2+ +Ti(3)F6 for example, it was shown that the calculation parameters of this system may be used just as the initial assessment.
Double Salt Ionic Liquids for Lignin Hydrolysis: One Cation for Catalyst and Solvent Anions
Authors: Cui Xianbao , Li Kai , Choudhary Hemant , Shamshina Julia L. , Rogers Robin Don 
Published: February 2020

Humanity has always relied on Nature for survival, but today we take oil as a feedstock and use it to produce chemicals to suit any purpose, from fuels and medicines to plastics. By reducing our reliance on Nature, we have forgotten our respect of Nature in the process. The world is now covered in oil in the form of non-biodegradable synthetic plastics which mar our landscapes and threaten our oceans. By 2050 there is predicted to be more plastic in the ocean than fish. At the same time, plastics represent a $654 billion market worldwide and are ubiquitous in modern life. Simply eliminating synthetic plastic use with no viable alternatives would be almost impossible and catastrophic from both a social and economic point of view.
Chemists make new chemicals and that has led to the development of a chemical industry that knows how to sell these chemicals. The more chemicals we make, the more the industry seeks new and better markets to sell them into. New, more sustainable technologies have been forced into the business of ‘replacements’ and must follow the same commercialization pathways as the old technologies they are trying to replace. The unsustainable practices, however, have often had decades or more head start and thus the economics to replace them are often insurmountable without government or policy intervention. The technologies to directly replace synthetic plastics with renewable biopolymers from plants and animals are there, but the consistencies of supply and economies of scale to make them competitive are not.
With a plethora of abundant natural and renewable resources (in terms of both quantity and diversity), from water purification - to cosmetics - to medical applications, the quality of human life can greatly benefit (and improve at the same time) from new, innovative technologies using building blocks obtained directly from plants and animals. With this mission in mind, we are exploring the entire range of the “biorefinery concept,” from dissolution, and conversion of plant and animal resources into value added chemicals and extraction of essential oils or vital chemicals, to isolation of pure biopolymers and production of new biomaterials from them. Because we can directly dissolve Nature’s raw materials, we can shape them, functionalize them, blend them, and use other non-chemistry means to produce advanced functional materials. These new, innovative materials represent new market opportunities which we will develop and promote.
Surfactant Ionic Liquids for Supercapacitors
Authors: Xu Ningjin , Klein Jeffrey Michael , Huang Phoebe , Gurkan Burcu 
Published: February 2020

Supercapacitors are electrochemical energy storage devices that find use in many electronic devices as well as increased application in large high-power requirement devices. The primary advantages of using a supercapacitor are the fast charge/ discharge rates and the long cycling lifetime. Traditionally supercapacitors have utilized organic or aqueous electrolytes both of which introduce significant drawbacks. For example, organic electrolytes are flammable which creates safety considerations that need to be addressed while aqueous electrolytes are limited to the electrochemical stability of water (1.23 V). Ionic Liquids (ILs) are a growing class of electrolyte that offer increased thermal and electrochemical stability over standard electrolytes. Additionally, ILs are non-flammable and are non-volatile, eliminating the possibility of flammable devices. Despite the advantages of IL electrolytes, they are highly viscous and do not easily access the pores of the electrode material in supercapacitors. Most commonly, high surface area carbon is used as supercapacitor electrodes but is only effective if the pores are filled with electrolyte. It is expected that successful wetting of the electrode surface will make IL electrolytes competitive with the current state of the art. Here, new surfactant ILs are synthesized and assessed as the electrolyte in supercapacitors containing porous carbon electrodes.
The physical properties of ILs can be tailored by modification of the anion and cation structures. Here, a mixture of surfactant ILs was used as the electrolyte which is shown to offer enhanced capacitance over the parent ILs. Each surfactant IL was synthesized in house and characterized through NMR, TGA, as well as viscosity and conductivity measurements. Capacitance, calculated from the integration of cyclic voltammograms, is shown to depend on the concentration of each IL and temperature, which is attributed to the changes in viscosity and conductivity of the mixture. Improved capacitance in supercapacitors with porous carbon electrodes can be related to lower surface tension and increased wettability of the porous electrodes the surfactant IL additive. In addition we demonstrate a significant thermal operating window of the proposed electrolyte.
Photoelectrochemical and Impedance Spectroscopy Investigation of Water Oxidation Reaction over Coordination Polymers Decorated TiO2 Nanotubes Arrays Electrodes
Authors: Rosas-Barrera Kevin Leandro , Pedraza Julio Andrés , Reguera Edilso , Acevedo-Peña Prospero 
Published: February 2020

Loading a cocatalyst onto a photoelectrodes is a wide spread strategy to enhance the efficiency of the photoelectrochemical water splitting process [(Yang, Wang, Han, & Li, 2012)]; however, its performance is strongly dependent of the method employed to form the heterojunction between cocatalyst and photoelectrode, as well as the alignment of their energetic levels to separate successfully the photogenerated charge carriers. In this study, we report water splitting photoanodes constituted from TiO2 nanotubes arrays decorated with coordination polymers as cocatalyst. Highly ordered TiO2 nanotubes were synthesized by the electrochemical anodization process of titanium (Ti) foil in a 0.2 M NH4F, ethylene glycol/10% H2O electrolyte under constant anodization time and applied potential. Coordination polymers were deposited onto TiO2 nanotubes by using the low cost successive layer adsorption and reaction (SILAR) method. Cocatalyst was successfully deposited on TiO2 nanotubes with tunable loading amounts by controlling the deposition cycles of SILAR. The structural characterization, morphology, elemental composition and light absorption capability of the samples were characterized by XRD, RAMAN, FT-IR, FE-SEM, EDX and UV–Vis methods respectively. Furthermore, the semiconducting properties of the modified TiO2 nanotubes were also estimated from Mott-Schottky plots. It was found that under illumination, the cocatalyst can efficiently collect photogenerated holes from the TiO2 nanotubes electrodes promoting charge separation and lowering the onset potential which yields an increased water oxidation efficiency.
Yang, J., Wang, D., Han, H., & Li, C. (2012). Roles of Cocatalysts in Photocatalysis and Photoelectrocatalysis. Accounts of Chemical Research, 46(8), 1900–1909. https://doi.org/10.1021/ar300227e