bluuebunny/crossref_metadata_2025_split huggingface dataset:
First-Principles Based Modeling of Li-Metal/Solid-Electrolyte Interfaces in Application to Li-Batteries
Authors: Cheng Tao , Merinov Boris V , Kozinsky Boris , Goddard William A 
Published: February 2020

All solid-state batteries could store significantly higher energy compared to conventional lithium-ion batteries using liquid electrolytes, simultaneously highly increase the safety. They are promising for future wide applications, such as wearable device, phones and even electric cars. However, several critical issues (e.g. low conductivity of solid electrolyte, mechanical and chemical stabilities of interfaces etc.) need to be solved before commercialization of all solid-state batteries. The knowledge of the fundamental aspects of these issues would highly accelerate the process of searching and designing the advanced materials and structures for efficient and low cost all solid-state batteries. The interfacial interactions are complicate and difficult to characterize experimentally. There is insufficient understanding of the interface formation processes and factors affecting interfacial structures, charge transfer and ion transport, chemical and mechanical stability and degradation. We use first-principles based methods, such as QM and ReaxFF [1] reactive molecular dynamics (MD) to achieve better understanding of these problems. A family of sulfide ceramics, so-called Li-argyrodites, Li6PS5X (X = Cl, Br, I), shows high ionic conductivity (~7 · 10−3 S/cm at 298 K) [2] and might be considered as a possible candidate for solid electrolyte for Li-batteries. These materials can provide a balance of efficiency and price. We have built the Li6PS5Cl structure and Li/Li6PS5Cl interface and performed QM MD and ReaxFF MD simulations on this systems. The results of these simulations will be reported together with results obtained for some other interface systems of interest.

Acknowledgements. This work was financially supported by Bosch Energy Research Network Grant No. 13.01.CC11.

References

[1] A.C.T. van Duin, .C.T., S. Dasgupta, F. Lorant, W.A. Goddard III “ReaxFF: A Reactive Force Field for Hydrocarbons” J. Phys. Chem. A 105,9396-9409, 2001.
[2] H.-J. Deiseroth, S.-T. Kong, H. Eckert, J. Vannahme, C. Reiner, T. Zaiβ, M. Schlosser ”Li6PS5X: A class of crystalline Li-rich solids with an unusually high Li+ mobility” Angew. Chem. Int. Ed. 47, 755-758, 2008.
(Invited) Insights into Solvation, Dynamics and Stability of Electrolytes for the Design of Novel Multivalent Systems from Coupled Molecular Dynamics and First-Principles Modeling
Authors: Persson Kristin A , Rajput Nav Nidhi , Qu Xiaohui 
Published: February 2020

Within the Joint Center for Energy Storage (JCESR) we have developed a high-throughput infrastructure for the automated calculation of molecular properties with a focus on battery electrolytes. Computational screening techniques have been found to be an effective alternative to the trial and error of experimentation for discovery of new materials. Using this infrastructure, we have computed the ionization potential (IP) and electron affinities (EA) of 16,000 molecules relevant to electrolytes targeting both multivalent intercalation as well as non-aqueous redox flow systems. For some potential multi-valent electrolytes we use classical molecular dynamics simulations coupled with ab initio calculations for Mg salts in various solvents. We uncover a novel effect between concentration dependent ion pair formation and anion stability at reducing potential, e.g., at the metal anode1. We elucidate systematic correlations between molecular level interactions and composite electrolyte properties, such as electrochemical stability, solvation structure, and dynamics.
Specifically, we find that multivalent electrolytes are highly prone to ion pair formation, even at modest concentrations, for a wide range of solvents with different dielectric constants, which have implications for dynamics as well as charge transfer. For example, at Mg metal potentials, the ion pair undergoes partial reduction at the Mg cation center (Mg2+→Mg+), which competes with the charge transfer mechanism and can activate the anion to render it susceptible to decomposition. Specifically, TFSI− exhibits a significant bond weakening while paired with the transient, partially reduced Mg+. This information provides critical design metrics for future electrolytes as it elucidates a close connection between bulk solvation and cathodic stability as well as the dynamics of the salt. We use our previous insights to design for new Mg electrolyte anions with the aim to stabilize the electrolyte during possible ion pair formation and charge transfer reactions. Through comprehensive calculations using both first-principles as well as well-benchmarked classical molecular dynamics, we proposed 16 new electrolyte salts. Based on successive property evaluation such as electrochemical stability window, chemical decomposition and hydrolysis vulnerability we down-select 4 potential new anions for Mg electrolytes.

References

[1] N. N. Rajput, X. Qu, N. Sa, A. K. Burrell, K.A. Persson, “The Coupling between Stability and Ion Pair Formation in Magnesium Electrolytes from First-Principles Quantum Mechanics and Classical Molecular Dynamics”, Journal of the American Chemical Society, 2015.
[2] X. Qu, A. Jain, N. N. Rajput,Y.Zhang, S.P.Png, M. Brafman, L.Cheng, E. Maginn, L.A. Curtiss, K.A. Persson, “Electrolyte Genome Project: A Big Data Approach in Battery Materials Discovery”, Computational Materials Science, 2015.
Computational Study of Li2SnO3 and Li2SnS3
Authors: Howard Jason David , Holzwarth Natalie A. W. 
Published: February 2020

First principles simulations were used to study Li ion mobilities in Li2SnO3 and Li2SnS3. These simulations determined the activation energies (Ea) for Li ion migration primarily considering the vacancy mechanism; calculations for the interstitial mechanism are ongoing. Experimental values for Ea
are available for each material [1, 2 ]. For over a decade, Li2SnO3 has been of interest as a promising anode material. It is known that when lithiated, Li2SnO3 will undergo an irreversible decomposition to Li2O and SnLix alloys [3]. The residual Li2O matrix is said to stabilize the volume change during charging/discharging of the SnLix anode [4]. It is of primary interest to investigate both Li2SnO3 and Li2SnS3 for these properties using simulations.
Acknowledgments
The computational portion of this work was supported by NSF grant DMR-1105485. Computations were performed on the Wake Forest University DEAC cluster, a centrally managed resource with support provided in part by the University.
References
[1] J. A. Brant et al, Chemistry of Materials
27, 189-196 (2015)
[2] L. P. Teo et al, Ionics
18, 655–665 (2012)
[3] I. A. Courtney and J. R. Dahn, J Electrochem. Soc.
144, 2045–2052 (1997)

[4] D.W. Zhang et al, Journal of Alloys and Compounds
415, 229–233 (2006)
(Keynote) Imaging Electrochemical Growth Using Liquid Cell Transmission Electron Microscopy
Authors: Ross Frances M 
Published: February 2020

Transmission electron microscopy is very helpful in measuring structure and composition after electrochemical growth has finished. However, it is also possible to image structures while they are still growing, by carrying out electrodeposition inside the electron microscope. The trick is to confine the electrolyte in a layer that is thin enough to be transparent to the imaging electrons – of the order of a few hundred nanometers – and to include electrodes with a geometry that allows the reaction to be controlled and visualized. To do this, we use microfabrication techniques to build liquid cells with thin windows of silicon nitride. Once filled with electrolyte, a liquid cell is placed in the microscope and controlled by a potentiostat during imaging. We can then relate changes in morphology to electrochemical parameters, providing a detailed probe of growth mechanisms with good temporal and spatial resolution.
In this presentation, we first describe practical aspects of liquid cell electron microscopy, particularly the competing requirements of resolution and diffusion – in other words, the extent to which a liquid layer that is thin enough to provide high resolution images can also replicate a process of interest. We then describe measurements of nucleation and growth during the deposition of metal films, and quantify the onset of growth instabilities. We show movies of the interface evolution of galvanostatically deposited Cu from an acidic electrolyte: initially, the kinetics are consistent with kinetic roughening theory, and later, with diffusion limited growth models. Macroscale models appear to predict the behavior over long length and time scales, but short scale behavior differs from spatially averaged measures, affecting the onset of the instability. We demonstrate some control of interface evolution through pulse plating and inorganic additives. We finally discuss liquid cell microscopy of electroless deposition and of corrosion processes in metal films, and combine metal dissolution with reduction by the electron beam to produce nanostructures. Developments in equipment and modelling are making liquid cell microscopy increasingly quantitative, suggesting exciting possibilities for detailed interrogation of a wider range of electrochemical growth physics.
(Invited) A Coverage Dependent Behavior of Pt on Au Deposited Using Surface Limited Redox Replacement
Authors: Vasiljevic Natasa , Al Amri Zakiya 
Published: February 2020

Different Pt bimetallic nanostructures, such as ultrathin Pt overlayers, alloys and nano-clusters, have been a focus of intense research because of their enhanced catalytic activity compared to the bulk Pt. Over the last few decades our fundamental understanding of the effects responsible for their electro catalytic behavior, such as bifunctional, electronic and ensemble effects, has advanced by the development of theoretical models and studies on model 2D systems enabled by development of new electrodeposition methods and routines to control their structure [1-4].
Studies of Pt-nanoclusters have shown strong correlation of surface activity with the structure and distribution of Pt on the surface [4, 5]. An enhancement of CO tolerance on supported Pt/Ru catalysts obtained by spontaneous deposition has been shown at a considerably lower Pt loading than on the commercial catalysts [6]. The modified Au surface with Pt nanosize clusters coverage as low as 15-25% of the substrate area, exhibit very high activity and improved selectivity toward dehydrogenation of formic acid (HCOOH) [7]. Most recently formation of Pt monolayer catalysts and nanoclusters using Surface Limited Redox Replacement (SLRR) method has been used to show the effect of strain and morphology on the catalytic behaviour [4].
Here in this work we present the study of Pt-nanoclusters on Au substrate as a function of their size, and areal coverage. We compared the design of Pt nanoclusters using two electrochemical approaches: i) spontaneous deposition (SD) i.e. reduction of the spontaneously adsorbed Pt-complex and ii) the surface limited redox replacement (SLRR) method based on the redox replacement of Pb underpotentially deposited layers. For each method successive application of optimized electrodeposition protocols yielded increased Pt surface coverage ranging from 0.25 to 1 area fraction. Using two different methods enabled design of nanocluster with varied cluster sizes and the areal coverage of Au. The structure and distribution of Pt nanoclusters was determined by electrochemical techniques (H-UPD and CO adsorption) and scanning tunneling microscopy (STM). Their catalytic behavior was analyzed and compared during formic acid electro-oxidation.
References:
1. W. Chrzanowski; H. Kim and A. Wieckowski, Catal. lett., 50 (1998), 69.
2. S. R. Brankovic, J. X. Wang, R. R. Adzic. Surf. Sci. 474, (2001), L173.
3. L. Bromberg, M. Fayette, B. Martens, Z. Luo, Y. Wang, D. Xu, J. Zhang, J. Fang, and N. Dimitrov, Electrocatalysis, 2013, 4 (2013), 24.
4. R. Loukrakpam, Q. Yuan, V. Petkov, L. Gan, S. Rudi, R. Yang, Y. Huang, S.R. Brankovic and P. Strasser, Phys.Chem.Chem.Phys.,16 (2014), 18866.
5. B. Du and Y. Tong, J. Phys. Chem. B, 109 (2005), 17775.
6. S. Brankovic; J. McBreen and R. Adzic, J. Electroanal. Chem., 503 (2001), 99.
7. M. Obradović; A. Tripković and S. Gojković, Electrochim. Acta, 55 (2009), 204.
Cu Underpotential Deposition on Ru(0001)
Authors: Brankovic Stanko , Wu Dongjun 
Published: February 2020

The underpotential deposition (UPD) has attracted research attention for many years due to its fundamental and practical importance[i]. Development of scanning probe methods (STM and AFM), and X-ray scattering techniques has enabled mechanistic in situ studies for many substrate-adlayer systems with great insight in details of UPD adlayer formation and structure, alloying and anion co-adsorption[ii]. However, in some cases, the noble metal surfaces with complex reactivity and interaction with water based electrolytes have rendered UPD studies a very difficult endeavor. One example is Ru surface for which a just few UPD studies have been reported[iii]-,[iv],[v],[vi],[vii].
Our talk presents a study of Cu UPD on Ru(0001). The Ru(0001) surface was prepared by annealing at 1400 C for one hour in Ar+H2 atmosphere (96:4), Figure 1. After cooling the Ru surface was protected by CO-saturated 0.1 M HClO4 solution and transferred to the electrochemical cell or STM cell for further studies. The example of the cyclic voltammetry and insitu STM results are shown in Figure 1. The potential has been gradually changed towards the region where Cu UPD on Ru(0001) occurs and high resolution/quality STM images were recorded. The morphological change of Ru(0001) surface due to Cu UPD process were correlated with CV data and characteristic cathodic and anodic peaks in CV were associated with particular features/process occurring during Cu UPD deposition and/or stripping. The Cu UPD process and adlayer structure on Ru(0001) is compared with corresponding Cu UPD process on other closed pack surfaces such as Au(111) and Pt(111). The apparent similarities and differences were identified and discussed during the talk.
The authors acknowledge the support from NSF Chemistry division under the contract # 0955922.

Figure 1. Cyclic voltammetry for Cu UPD on Ru(0001), scan rate 10 mV/s. Solution: 0.1 M HClO4 + 10-3 M Cu2+. Inset shows Ru crystal during inductive annealing.

[i] S. Trasatti, J. Electroanal. Chem.
33, 351 (1971),
[ii] E. Budevski, G. Staikov and W. J. Lorenz in Electrochemical Phase Formation and Growth, ed. R.C. Alkire et al. VCH, Berlin (1996), see Ref. herein.
[iii] M. Vukmirovic, in Modern Aspects of Electrochemistry, vol. 42, ed. C. Vayenas et al. Springer, NY (2008).
[iv] N. Bogolowski, S. Huxter, A. –E. Abd-El-Latif,G.A. Attard, H. Baltruschat, Journal of Electroanalytical Chemistry, 646, 68 (2010).
[v] D. K. Gebregziabiher,Y-G. Kim, C. Thambidurai, V. Ivanova, P-H. Haumesser, J.L. Stickney, Journal of Crystal Growth,
312 1271 (2010).
[vi] Y. Zhang, L. Huang, T. N. Arunagiri, O. Ojeda, S. Flores, O. Chyan, R. M. Wallace, Electrochemical and Solid-State Letters, 7 C107 (2004).
[vii] M. A. Quiroz, L. Salgado, Y. Meas, Electrochimica Acta, 33 435 (1988).

Figure 1
(Invited) Advanced Materials for Integrated on-Chip Power Converter
Authors: Deligianni Hariklia (Lili) , Wang Naigang , Jinka Oblesh , Yoon Joonah , O'Sullivan E. J. , Romankiw Lubomyr , Gallagher W. J. 
Published: February 2020

We describe electrolessly plated magnetic material
s
required for the demonstration of a monolithically integrated on-chip inductors. Miniaturization of magnetic inductors and integration on semiconductor chips requires the choice of high performance magnetic materials. The requirements are soft magnetic properties with low coercive force (Hc < 1.0) and high saturation magnetization, high resistivity (r >=110 mohm cm) to reduce inductor losses at high frequencies from eddy currents, and excellent thermal stability to a processing temperature that is dictated by the integration process on-chip (>200~250oC). This work demonstrates that a Co85W5P10 thin film deposited using electroless chemistry on a Pd activated Ni80Fe20 seed layer meets all the materials requirements for a low process temperature integrated inductor. A 1.2 mm thick CoWP layer deposited on a 60nm Ni80Fe20 seed layer has a resistivity of 110 mohm cm and its moment and anisotropy are stable after 200oC thermal cycling. The work also shows that the initial stages of growth, starting from the magnetic Ni80Fe20 seed layer surface, affect greatly the growth and thermal stability of the CoWP film. As far as maintaining a higher ~250°C thermal processing limit, we obtained encouraging data for CoWP and NiFeBP films thinner than 300nm grown by electroless deposition. We will also discuss approaches to achieving laminated films incorporating these materials.
Light Assisted Electrodeposition for the Metallization of Silicon Solar Cells
Authors: Huang Qiang , Papa Rao Satyavolu , Fisher Kathryn 
Published: February 2020

Cu electroplating is of a great deal of interest for the metallization of silicon solar cells due to its comparable resistance with the current silver metallizaion, and its lower cost for both the material and the operation.[1,2] However, the notorious Cu diffusion into Si is of great concern to the devices performance degradation during the life cycle of the cells. Ni silicide and Ni metal layers have been recently reported as part of the integration scheme to enable the Cu metallizaion and greatly improved the solar cell reliability.[3,4] The formation of this Ni silicide and Ni stack structure is to provide a low-resistance contact between the silicon and metal grid, a good adhesion of metal grid, and a diffusion barrier for the Cu. Among them, the Ni silicide formation needs to be well controlled so that it is not too thick to shunt the solar cell.
This paper will present the light assisted plating of Ni and the silicide formation on single crystalline silicon solar cells fabricated with CMOS p-Si on a semiconductor line. The solar cell substrates for plating comprise ~ 60 ohm/sq emitter formed by POCl diffusion, PECVD SiN passivation layer, and evaporated Al back surface field. Electrodeposition of Ni was studied on 4 cm x 4 cm solar cells in different solutions containing Ni salt and other plating additives. Back contact through the Al BSF was used and front-side illumination was applied. Silicidation was achieved by rapid thermal annealing at different temperatures for different time. The study is focused on the effect of light, chemistry and the plating current on the film in terms of morphology, impurity and its salicidation.
Figure 1 shows the relation between the applied potential and the light intensity at different constant current densities. Two regions of operation were clearly observed with a threshold light intensity. At high illumination, when enough carriers were generated by the light, the plating occurs at the forward bias mode of the diode. As the light intensity decreases below a threshold value, the potential increases significantly and stays at a high value indicating the diode operates at reverse bias mode. The threshold light intensity is dependent on the illumination energy spectrum, solution absorbance, anode shadowing and applied current density.

REFERENCES

D. A. Yates, US Patent 4,609,565 (1986).

K. Holdermann, US patent 5,543,333 (1996).

J Bartsch, A Mondon, K Bayer, C Schetter, M Horteis, and S W Glunz, J. Electrochem. Soc., 157, H942 (2010).

J Bartsch, A Mondon, C Schetter, M Horteis, S W Glunz, IEEE 35th PVSC, Honolulu HI (2010).

Figure 1
Hybrid Electro-Electroless Deposition (HEED)
Authors: Petro Robert , Schlesinger M. 
Published: February 2020

Hybrid electro-electroless deposition (HEED) is a novel thin film metal deposition technique developed in Windsor. The process combines both electroplating and electroless deposition within a single electrolyte. The two deposition processes upon which HEED is based are combined such that each individual process targets a distinct metal ion for reduction. The nature of the deposit is determined by the composition of the electrolyte and electroplating potential applied, among other well established factors for both individual techniques. The process of HEED allows the formation of composite, alloyed, and multi-layered, or compositionally modulated alloy, deposits. Composite HEED deposits are somewhat uncommon as one of the two techniques must produce well defined grains. Alloyed HEED deposits are produced under two sets of conditions. Either each individual technique comprising HEED, electroplating and electroless deposition, is made to deposit an alloy [1], or each technique deposits a thin layer for the purpose of interlayer diffusion. Multi-layered HEED deposits are produced wherein each technique deposits pure, or nearly pure, metallic layers which nominally do not diffuse into one another [2]. The novelty of the HEED process may be illustrated with the deposition of metals of similar nobility, such as nickel and cobalt, in a multi-layered deposit [2]. The HEED multi-layers are in contrast to the standard method of electroplated multi-layers wherein the deposition potential and electrolyte support nearly pure layer deposition where the metals are of differing nobility [3].
[1] Robert Petro and Mordechay Schlesinger, “Development of Hybrid Electro-Electroless Deposit (HEED) Coatings and Applications”, Journal of The Electrochemical Society, 161(10), (2014), p.D1-D6
[2] Robert Petro and Mordechay Schlesinger, “Deposition of Cobalt-Nickel Hybrid Electro-Electroless Deposited (HEED) Modulated Multilayers”, Journal of The Electrochemical Society, 162(4), (2015), p.D154-D158
[3] K. D. Bird, M. Schlesinger, “Giant Magnetoresistance in Electrodeposited Ni/Cu and Co/Cu Multilayers”, Journal of The Electrochemical Society, 142(4), (1995), p.L65-L66