bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploring the Effects of Doping on the Electrochemical Performances of LiCoO2 at High Cut-Off voltage
Authors: Zhang Jienan , Zhao Enyue , Wang Yi , Wang Junyang , Wang Fangwei , Yu Xiqian , Li Hong 
Published: February 2020

Increasing the energy density of cathode materials for lithium-ion batteries requires raising up the working voltage of cathode materials or/and extracting more lithium ions from their crystal lattice. Therefore, the cathode materials are inevitably exposed to extreme working environment, which may cause the instability of both global crystal structure and/or surface/interfacial structure. Introducing doping elements to electrode is currently the expedient method to improve the performance, however, whether the alien element is doped in the host crystal or not usually lacks of solid experimental proofs, and whether the positive effects is caused by doping is still unknown. The situation becomes even more complex when several elements are doped at the same time. In this report, with a case study focusing on LiCoO2, evaluation of the interaction between different alien elements including Ti, Mg and Al is conducted with orthogonal experiments. The effects of doping and coating are compared in detail to find out a better way to improve the electrochemical performances of LiCoO2 at high cut-off voltage of 4.6V vs. Li+/Li. The question regarding whether the alien elements are doped in the host crystal or presented as a secondary phase that is aggregated on surface or grain boundaries is also discussed with both first-principle calculations and experimental investigations, such as XRD, X-ray imaging, XPS, thermal analysis by TG and electrochemical tests. By summarizing the results, the major factors affecting the performance of high voltage LiCoO2 are clearly demonstrated, which we hope it will also be valuable information for the development of other cathode materials for high energy density lithium-ion batteries.
(Invited) Post Lithium-Ion Technologies: Novel and Sustainable Materials for Energy Storage
Authors: Hintennach Andreas 
Published: February 2020

Ever since the development of lithium-ion batteries the spirit of invention has mainly lead to an evolution of existing materials. With the focus on olivine and Nickel- and cobalt based materials the energy densities, power densities and ageing mechanisms could be investigated over the years and support the understanding of the underlying mechanisms of electrochemical energy storage and conversion.
With increasing numbers of cells being used in the world the need of a Post-Lithium-Ion technology emerges due to a limited availability of highly pristine nickel and cobalt and increasing need for recycling, environmental protection and overall energy efficiency. Nevertheless the is still an ongoing and very promising approach for e. g. novel stoichiometries of NMC materials, Lithium cobalt phosphate and nickel-rich materials with can significantly increase the energy density. Due to the very high reactivity and potential (i. e. 4.5 V) these materials require highly stable electrolytes.
Finally, lithium-sulphur can lead to a highly recyclable, environmentally friendly system. Having a silicon-based anode (> 85 % Si) included both volumetric and gravimetric energy density can mean an interesting alternative to metal-oxide based materials.
With the increased energy density, safety becomes a more and more important aspect in thermodynamic and kinetic investigations of these materials. This aspect can lead to the development of non-flammable electrolytes or solid state cells.
Solid state cells are a very different but highly promising approach. Having a solid-solid interphase between electroactive materials and electrolyte the chemicals mechanisms significantly change to solid state chemistry rather than solid-organic interphases chemistry.
All types of novel chemistries exhibit very different chemical mechanisms which require specific synthetically work for electrolytes, additives, binders, carbon materials, and even the surfaces of the electro-active materials itself.
Enhanced Electrochemical Performance of the Cathode for a Lithium Ion Secondary Battery Using Lithium Ion Conductive Glass-Ceramics
Authors: Katoh Takashi , Satoh Ryouhei , Nakajima Kousuke , Hoffman Brion 
Published: February 2020

Ceramics powder such as SiO2 and Al2O3 are incorporated in to the polymer electrolyte to form the composite film for the sake of improving ionic conductivity, mechanical and thermal properties. Though these filler enhanced ionic conductivity of gel electrolyte due to the disruption of polymer matrix and increasing micro pores, these are not ionic conductive material. We found that the gel electrolyte film (Pvdf based polymer) was enhanced ionic conductivity by adding LICGCTM.
We have developed lithium ion conducting glass-ceramics LICGCTM with a NASICON type structure for solid lithium ion electrolyte.1-
3) The ionic conductivity of the glass ceramics with a Li1+x+yAlxTi2-yGeyPO4 composition shows over 1×10-4 Scm-1 at room temperature. Such ceramics have a very stable in ionic conduction. In addition, the ionic conductivity does not decrease, even if it was soaked in an aqueous of Li salt solution4-5), and does not lose the weight in boiling distilled-water for 1 h. The glass-ceramics with the crystalline form of Li1+x+yAlxTi2–xSiyP3–yO12 with a NASICON-type structure by heat-treated glass with a specific composition1-2). This glass-ceramics has a high lithium-ion conductivity that is equal to or more than 10–3 Scm–1at room temperature. Furthermore, because it is very stable in the atmosphere and even to exposure to moist air, it is possible to use this material to apply a solid-electrolyte for a lithium ion secondary battery using organic liquid electrolyte.
In this work, the effect of LICGCTM as additive for a lithium ion secondary battery was investigated. We synthesized LiCoO2 cathode with 5wt.% LICGCTM filler and evaluated it the charge and discharge property using a half cell. We confirm the rate performance at room temperature is enhanced at 0.2-3.0C comparing pristine LiCoO2 cathode. The rate performance was indicated 20 percent increasing at 2.0C rate as compared to pristine LiCoO2 cathode. The charging performance was also enhanced at higher rate at room temperature.
Implementation of Tin Dioxide/Graphene/Graphene Oxide for High Capacity and Long Cycle Life Supercapacitors and As Anode Material for Lithium Ion Batteries
Authors: Dorvilien Valerio , LopezdeVictoria Monica , Rivera Kevin , Suleiman Amal , Tripathi Balram , Mendoza Frank , Cabrera Carlos , Morell Gerardo , Weiner Brad R. 
Published: February 2020

Energy storage and conversion mechanism are different for on lithium ion batteries (LIB) and supercapacitors (Electrical Double Layer Capacitors- EDLCs), materials that can be used for both could lead in the future the energy storage and conversion technologies. We explored a non-conventional process to synthesize SnO2/G/GO composite powder which is conformal structure was characterized under different techniques. Comprehensive analysis of the structural and chemical properties reveals that the material consists of highly dispersed SnO2 nanoparticles in G/GO matrix.
The dispersed SnO2/G/GO suspension was coated an aluminum foil for the supercapacitors electrodes. We examine the electrical conductivity of the electrodes by atomic force microscope (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). We assembled the Al coated SnO2/G/GO composite as a supercapacitor inserting one solid-state electrolyte between two electrodes, assembled into a sandwich structure. The specific capacitance and cycle-life stability of the supercapacitor was investigated by cyclic voltammetry analysis. For LIB applications, the SnO2-G/GO composite exhibited high capacity and excellent electrochemical performance as anode material. For both applications, the quantitative/qualitative results show that G/GO is providing contact areas which results in more energy density at the interface electrode/electrolyte and that the SnO2 provides additional ions to the EDL and the electrochemical process. The Overscreening phenomena observed, which is a function of ionic size, surface charge density of the electrodes, can also be a function of concentration of the electrolyte, porosity of the electrodes (G/GO) and the ions provided to the electrode/electrolyte interface by the electrode.
(Keynote) Mechanisms and Selectivity of the Electrochemical CO2 Reduction Reaction on Multiple-Site Versus Single-Site Catalysts
Authors: Strasser Peter 
Published: February 2020

Strategies toward closing the anthropogenic carbon cycle using the chemical conversion of CO2 in off-gas streams of steel-mills or cement-plants into useful molecules have become a scientific and technological priority. Of all chemical ways to convert CO2 into hydrocarbons, the direct electrochemical coupling of water electrolysis and CO2 reduction appears attractive, as it is a one-pot process step, occurs at ambient temperature and pressures, involves solely water and CO2 as reactants, and may involve renewable electricity from wind, solar or hydro power plants.
The CO2 electroreduction to gaseous C1 products such as CO or CH4 is often carried out on the surface of metal catalysts such as Cu, Ag or Au. At industrially relevant current densities and electrode potentials, however, these catalysts typically suffer from low faradaic C1 product selectivities due to the competing, very fast reduction of water, i.e. the hydrogen evolution reaction. New catalyst concepts with tunable selectivity for hydrogen evolution versus CO2 reduction are needed(1-3).
In this contribution, we share recent experimental and computational mechanistic studies(4) on the electroreduction of CO2, CO, HCOH on metallic multi-site versus metal/heteroatom-doped carbon single-site catalysts. We provide new insight into CO selectivity trends and put particular emphasis on the competing reaction pathways to methane and methanol. We show that carbon-based single site catalysts are an intriguing cost-effective alternative to metals.
1. H. Mistry, A. S. Varela, S. Kühl, P. Strasser, B. R. Cuenya, Nanostructured electrocatalysts with tunable activity and selectivity. Nature Reviews Materials, 16009 (2016).
2. H. Mistry et al., Highly selective plasma-activated copper catalysts for carbon dioxide reduction to ethylene. Nat Commun, (2016).
3. A. S. Varela et al., Metal-Doped Nitrogenated Carbon as an Efficient Catalyst for Direct CO2 Electroreduction to CO and Hydrocarbons. Angewandte Chemie International Edition
54, 10758-10762 (2015).
4. A. Bagger, W. Ju, A. S. Varela, P. Strasser, J. Rossmeisl, Single site porphyrine-like structures advantages over metals forselective electrochemical CO2reduction. Catal Today, http://dx.doi.org/10.1016/j.cattod.2017.1002.1028 (2017).
(Invited) Electronic-Level Insight on CO2 Reduction Reaction
Authors: Lewera Adam , Gorzkowski Maciej T. , Jurczakowski Rafal Robert , Kulesza Pawel J 
Published: February 2020

There is general agreement that catalytic activity is correlated to electronic properties of the catalyst’s surface. For selected molecules and simple surfaces it was shown by Norskov and co-workers that the strength of adsorption of such molecule and the kinetics of the respective catalytic reaction can be correlated to theoretically predicted electronic properties of the surface, i.e. catalyst d-band center (in relation to Fermi edge). However the calculated energy of the d-band center cannot be always correlated to catalytic activity, and the calculated electronic structure (DOS) is not always representative of the experimentally determined electronic structure, especially for non-uniform systems. This is the major drawback of the theoretical approaches currently being used to predict or explain the observed catalytic activity. Thus for assessing the factors responsive for catalytic activity, experimental determination of surface electronic structure is imperative.
X-ray Photoelectron Spectroscopy (XPS) and UV Photoelectron Spectroscopy (UPS) experiments are often used to study the electronic properties of materials. In particular core-level electron’s binding energy and valence band (VB) electron’s density of state can be determined using XPS and UPS. Due to interactions of ejected photoelectrons with matter those experiments are in general limited to the Ultra-High Vacuum (UHV) conditions (ca. 10-9 mbar). In the recent years however the Near Ambient Pressure X-ray Photoelectron Spectroscopy/UV Photoelectron Spectroscopy techniques (NAP XPS/UPS) were developed, allowing for local (at the sample surface) increase in pressure up to tenths of millibars, bridging the gap between UHV adsorption studies and real-life systems. Using of the NAP methods presents unique opportunity to study the electronic properties (and changes of electronic properties) of surface during the adsorption from gas phase. This is of paramount importance as insight can be gained on electron-level interactions between the surface and adsorbing molecule, bond breaking/bond forming and similar phenomena, which was not possible before.
Investigating the electronic properties of catalysts, in particular valence band DOS, in both – Ultra-High Vacuum (UHV) and Near Ambient Pressure (NAP) conditions allows for experimental determination of electronic-level properties of surface in absence and presence of CO2 molecule, the electronic-level changes induced by CO2 adsorption and experimental verification of CO2 adsorption theories. It can be expected that utilizing NAP XPS will results in better understanding of CO2 adsorption processes, fine-tuning the theoretical models and advance the science and technology of catalytic CO2 reduction.
(Invited) Silicon Nanowires Photocathodes Combined with Mn-Based Molecular Complex Catalysts for the Efficient Light-Driven Electrocatalytic Reduction of CO2 to CO
Authors: Fabre Bruno , Chardon Sylvie , Torralba-Penalver Encarnacion 
Published: February 2020

Proton-assisted multielectron reduction potentials for CO2 lie within the bandgap of several semiconductors, in such a way that their use as photocathodes for this reaction allows a substantial decrease in the energy input required [1-3].
In the present work, hydrogen-terminated silicon nanowires (SiNWs-H) are used as a photocathode for the electrocatalytic reduction of CO2 in the presence of different metallic bipyridyl complexes. Due to their nanostructured surface, SiNWs are highly interesting as light-harvesting electrodes, being efficient in converting solar to electrical energy, easy to make and stable under reduction conditions [4]. Among the tested complexes, we have used Mn non-noble metal based complexes to catalyze CO2-to-CO photoelectroreduction, which is a less expensive approach versus the traditionally used based on rare and noble metal complexes [5].
The photoelectrochemical reduction of CO2 at p-type SiNWs-H was achieved at potentials significantly lower than those required with a glassy carbon electrode (GCE) and planar Si-H [6]. Thus, for intermediate reduction potentials the photocurrent density values provided by silicon were noticeably higher than the current densities provided by GCE. Besides, impedance spectroscopic measurements were carried out and combined with cyclic voltammetry data to obtain the quantitative complete characterization of the energetics of all the systems studied. All the experiences were carried out at p-type flat silicon for comparison purposes and key electrocatalytic parameters such as fill factor (FF) and energy conversion efficiency (η) were determined.
Finally, in order to develop technologically viable electrocatalytic devices, the elaboration of SiNWs−H photoelectrodes modified with a Mn-based complex has been successfully achieved from an electropolymerizable catalyst, and it was shown that the electrocatalytic activity of the complex was retained after immobilization.
[1] Aresta, M. et al., Chem. Rev. 2014, 114, 1709.
[2] Costentin, C. et al., Chem. Soc. Rev.
2013, 42, 2423.
[3] Schmidt-Mende, L. et al., Angew. Chem. Int. Ed.
2013, 52, 7372.
[4] Wang, D. et al., Angew. Chem. Int. Ed.
2012, 51, 6709.
[5] Kubiak, C. P. et al., J. Phys. Chem. C
2010, 114, 14220.
[6] Torralba-Penalver, E. et al., ACS Catal.
2015, 5, 6138.
(Invited) Carbon Dioxide Electroreduction at Ultrathin Palladium Layers Deposited on Copper Electrode
Authors: Jurczakowski Rafal Robert , Januszewska Aneta , Gorzkowski Maciej Tomasz , Lewera Adam , Kulesza Pawel J 
Published: February 2020

Electrochemical conversion of carbon dioxide into eligible fuels has become the subject of particular fundamental interest. Recently, we have reported electrochemical studies on CO2 electroreduction at multilayered catalyst composed of the monatomic layer of copper covering palladium overlayers (0.8-10 monolayers) deposited on the well-defined Au(111) surface [1]. In this study Carbon dioxide electroreduction has been studied at ultrathin palladium layers deposited on copper electrode. The Pd deposits have been prepared by using chemical methods. The spontaneous galvanic displacement and resulting uncontrolled deposition of the palladium on copper has been entirely eliminated by the use of palladium(II). This method allowed us for controlled and precise deposition of palladium layers by electrochemical methods. The deposits coverage was changed within the range 0.5 to 5 atomic monolayers. The effectiveness of the method and the durability of the obtained ultrathin palladium layers have been confirmed by X-ray photoelectron spectroscopy (XPS). XPS has been also used for detailed analysis of the electronic properties of the Pd/Cu systems. Significant chemical interactions of both elements resulted in a partial shift of the electron density from palladium to copper and in the changes in the symmetry of 3d palladium signals characteristic for two-dimensional palladium structures (Pd monolayers). A detailed analysis of the valence band structure of Pd/Cu was correlated to the catalytic activity of the studied systems. The unique properties of the valence band structure cannot be attributed to the simple superposition of pure metal bands (Pd and Cu). It has been shown that the increase in the electron density near the Fermi level results in a significant decrease in the overpotential of the carbon dioxide electroreduction. Analysis of the gaseous products obtained in the CO2 electroreduction was performed by gas chromatography. Adsorption of carbon dioxide on Pd/Cu layers was demonstrated by XPS measurements in the presence of 1 mbar CO2 in XPS measurements under near ambient pressure XPS (NAP-XPS).
[1] A. Januszewska, R. Jurczakowski, P. Kulesza, Langmuir 30(2014)14314-14321
A Comparison of Aqueous CO2 Reduction on Ni-Ga Thin Films and Nanoparticles
Authors: Francis Sonja A , Chu An T , Torelli Daniel A , Crompton J Chance , Lewis Nathan S , Bocarsly Andrew B. 
Published: February 2020

It was recently reported that thin films of nickel-gallium, prepared simply by drop-casting aqueous salt solutions onto graphite plates, were active for carbon dioxide reduction in aqueous carbonate electrolytes acidified to pH 6.8 with 1 atm CO2. The Ni-Ga thin films produce mixtures of methane, ethylene and ethane at potentials as anodic as -0.48V vs RHE, representing some of the lowest onset potentials for C2-product formation reported to date. While polycrystalline Cu also produces CH4 and C2H4, the onset potential for these products on Ni-Ga films is several hundred millivolts more positive. However, the current densities on Ni-Ga are ~ 3 orders of magnitude lower than Cu. One strategy to improve the current densities is the use of nanostructured Ni-Ga catalysts. Thus, we present a novel synthesis of Ni-Ga nanoparticles for the purpose of probing their carbon dioxide reduction behavior. Micrometer sized clusters of Ni3Ga nanoparticles (~8-13 nm in diameter) were synthesized from the reflux of Ni(COD)2 and Ga(acac)3 salts in 1-octadecene solvent at 310°C (COD = cyclooctadiene, acac = acetylacetonate). The nanoparticles were supported on carbon black (Vulcan XC-72) and fabricated onto a glassy carbon electrode with ionomer solution. Interestingly, in aqueous K2SO4 electrolyte saturated with 1 atm CO2 (pH 4.38), the Ni-Ga nanoparticles reduced CO2 to formic acid with Faradaic efficiencies as high as 36% at -0.92 V vs RHE. This contrasting activity to Ni-Ga thin films is discussed with an emphasis on the effect of composition, surface structure, and support of the catalyst.

Figure 1
An Open-Source Data Science Platform for the Electrochemical Community
Authors: Masse Robert 
Published: February 2020

It is no exaggeration to say that the lithium-ion battery has revolutionized the world, and the importance of electrochemistry has been brought to the fore as we look to improve batteries for electric vehicles, biomedical devices, and other critical applications.
However, electrochemical studies – particularly on batteries – are conducted with software tools that were not designed for the scale and the importance of the energy storage industry today. The software provided by hardware vendors often does not readily provide the answers we need, or even allow us to ask the right questions. Legacy software tools are often no better and suffer from severe stability issues. In industry, time is critical and most data goes unanalyzed, putting manufacturers at risk. Other firms build in-house tools that constantly reinvent the wheel.
We believe the community would be better served by working together with tools commensurate with the tasks we face. In recent years, several open-source software and hardware tools have been developed by the electrochemical community. However, most have only garnered modest traction. We believe this is driven by the high barrier of adoption, since most electrochemists are not also software developers, and because a significant amount of time and resources must be dedicated to supporting such projects.
Here we present an open-source web-based tool that lays the foundation for collaboration, and addresses the issues described above. Our platform is designed to accomplish the following:
1) Automate rote data analysis. Hours of analysis can be done in minutes or seconds to generate standard plots and statistics for cell capacity, voltage profiles, and cyclic voltammetry, as well as more involved analyses like incremental capacity or other user-defined functions. This is particularly important for batteries where both the number of electrochemical cells and cycles per cell may be very large and cumbersome to analyze thoroughly.
2) Reduce the barrier to enter and contribute to the platform. We provide APIs for a common framework for others to build upon. This saves time compared to developing a one-off application from scratch, and allows for greater impact when packaged together with a suite of other tools.
3) Catalyze electrochemical data science. The growing field of the data science allows for new tools to be developed to ask new questions and glean previously invisible insights from battery performance data.
We believe this software platform provides the missing infrastructure required to meet the demands of the electrochemical community today, and rise to the challenges of tomorrow.