Nascent SEI-Surface Films on Single Crystalline Silicon Investigated

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Nascent SEI-Surface Films on Single Crystalline Silicon Investigated by Scanning Electrochemical Microscopy Eduardo dos Santos Sardinha, Michael Sternad, H. Martin R. Wilkening, and Gunther Wittstock ACS Appl. Energy Mater., Just Accepted Manuscript • DOI: 10.1021/acsaem.8b01967 • Publication Date (Web): 22 Jan 2019 Downloaded from http://pubs.acs.org on January 24, 2019

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ACS Applied Energy Materials

Nascent SEI-Surface Films on Single Crystalline Silicon Investigated by Scanning Electrochemical Microscopy

Eduardo dos Santos Sardinha,1 Michael Sternad,2,# H. Martin R. Wilkening,2 Gunther Wittstock1,* 1

Carl von Ossietzky University of Oldenburg, School of Mathematics and Natural Sciences, Institute of Chemistry, D-26111 Oldenburg, Germany

2

Graz University of Technology (NAWI Graz), Christian Doppler Laboratory for

Lithium Batteries, Institute for Chemistry and Technology of Materials, A-8010 Graz, Austria

*Corresponding Author: [email protected] # Current address: M. S., Linz Institute of Technology, Froschberg 8, 4020 Linz, Austria

1 ACS Paragon Plus Environment

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Abstract Silicon is a promising high capacity host material for negative electrodes in lithium-ion batteries with low potential for the lithiation/delithiation reaction that is outside the stability window of organic carbonate electrolytes. Thus, the use of such electrodes critically depends on the formation of a protective solid electrolyte interphase (SEI) from the decomposition products of electrolyte components. Due to the large volume change upon charging, exposure of the electrode material to the electrolyte must be expected, and facile re-formation of SEI is a scope for improving the stabilities of such electrodes. Here, we report the formation of incipient SEI layers on monocrystalline silicon by in-situ imaging of their passivating properties using scanning electrochemical microscopy after potentiodynamic charging to different final potentials. The images show a local initiation of the SEI growth at potentials of around 1.0 V vs. Li/Li+ in 1 M LiClO4 in propylene carbonate. Keywords: silicon electrode, single crystalline electrode, solid electrolyte interphase, scanning electrochemical microscopy, incremental charging


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Introduction Lithium-ion batteries (LIB) are important rechargeable batteries used routinely for portable electronics and power tools. The higher demand with respect to cost, safety and long-term stability for electric vehicles and storage of intermittently harvested renewable energies1,2 require further improvements.3 LIBs combine two Li-ion host electrodes in the rocking chair configuration, i.e Li+ as working ions is moved between a transition metal oxide with a valence change of MnIII/IV, CoII/III or NiII/III and a negative electrode that takes up Li+ upon reduction at potentials close to the standard potential of Li|Li+. While graphite has remained the most important material for negative electrodes,4 silicon is considered as one of the promising alternatives due to its wide abundance, high Li-ion diffusivity in amorphous -LixSi5 and high theoretical gravimetric capacity of 3579 mAh g−1.6 During lithiation of Si, the potential of the Si electrode exceeds the stability window of the electrolyte causing its reductive decomposition.7 The reduction products form a protective solid electrolyte interphase (SEI) covering the Si electrode and being permeable for the Li ions.8–10 The properties of the SEI are pivotal for performance and long-term stability of a battery.8,9 Recurring lithiation/delithiation with the associated drastic volume change of 250-270%11 challenge the long-term stability of the SEI, cause the electrode material to crack with exposure of non-passivated Si surfaces and may result in irreversible loss of active material.12,13 Non-passivated Si surfaces are expected to form a new SEI layer.3 Thus, similar to metallic Li electrodes, the SEI layer is continuously re-formed and may remain instable during cycling14 leaving ample scope for its optimization.15 The first charging cycles is crucial for achieving this aim8 and has already received considerable attention.16 Different ex situ and in situ techniques, such as X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy 3 ACS Paragon Plus Environment


(AFM), surface-enhanced Raman spectroscopy (SERS), and scanning tunneling microscopy (STM),17 have been used to observe the film formation process and to study chemical and physical properties of the SEIs. Scanning electrochemical microscopy (SECM) offers the advantage of a direct in situ or in operando analysis of the passivating properties SEI in LIBs.18,19 It has been applied first to TiO2,20 graphite composite electrodes21 and other negative electrode materials,22,23 including Si with thin oxide layers.24,25 Here, we investigate highly conductive Si(100) electrodes without SiOx layer. In contrast to the previous inoperando study,24 we avoided lithiation/delithiation reactions because they cause macroscopic cracks in SEI layers that mechanically rupture SEI layers. Instead we focus on the incipient organic SEI layer formed at potential positive of the lithiation potential and which can be observed very clearly if the Si electrode is not covered by a native SiOx film. After

testing

different

mediators,

2,5-di-tert-butyl-1,4-dimethoxybenzene

(DBDMB) has proven to be the most suitable mediator for SECM experiments in carbonate-based electrolytes21,25 because of the sensitivity to small variation of SEI properties and stable operation in an Ar-filled glove box.21 Before, DBDMB has also been identified as promising overcharge protecting agent with similar requirements.26 With this mediator, dynamic behavior of the passivating properties of fully formed SEIs were observed.21–23 The SEI formation was achieved in a battery cell followed by a post mortem analysis in the SECM feedback mode21, or the Li+-insertion electrode was cycled while the microelectrode was held at a fixed position.24 While cycling of Si anodes has been studied extensively in the past,27 detailed investigations of the incipient, potential-dependent and spatially resolved SEI formation on pristine Si electrodes are still missing. Here, we accomplished for the first time series of SECM 4 ACS Paragon Plus Environment

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imaging on identical regions with intermittent formation of SEI layers on smooth single crystalline electrodes while avoiding lithiation and the associated strong morphological changes that would complicate the interpretation. The findings open doors for rationally optimized SEI formation protocols. Experimental Substrates. A Cu layer (1 µm thickness) was sputtered as current collector on the back side of the Si wafers (monocrystalline, 200 µm thickness, orientation, resistivity 8 m cm). After cutting the Si wafer into 4 mm × 4 mm pieces, the native oxide layer28 was removed by placing a drop of 100 µL of 5 mass-% hydrofluoric (HF) acid solution on the Si substrates while avoiding wetting the Cu current collector on the back side of the substrates. (Caution: HF solution is highly toxic and should be handled with extreme care.) The HF solution remained on the surface for one minute and was rinsed afterwards thoroughly with deionized water. The Si samples were then placed under vacuum for a few hours and transferred to an Ar-filled glove box (Uni-Lab, M. Braun GmbH, Garching, Gemany) for further SECM experimentation. Scanning electrochemical microscopy. SECM was carried out using the SECMx

control

software29

controlling

a

potentiostat

(CompactStat,

Ivium

Technologies, Eindhoven, The Netherlands), a 3-axis micropositioning system (MS30 precision actuator and PS30 distance measurement system, CU30 controller, mechOnics AG, Munich, Germany), and an in-house-designed electronic switch connecting either the microelectrode (ME) or the Si electrode as working electrode. SECMx was also used to run batch sequences of SECM experiments and experiments from the native software of the IviumStat potentiostat. The positioning system was placed under a custom-made plexiglas cover within an Ar-filled glove box.21 Potentiodynamic charging 5 ACS Paragon Plus Environment


was carried out using a potentiostat (Compactstat, Ivium Technologies, Eindhoven, The Netherlands) by linear sweep voltammetry (LSV) in a three-electrode configuration with the Si electrode as working electrode and two metallic Li foils as auxiliary and reference electrodes. Charging and imaging were performed in a solution of 5 mM 2,5di-tert-butyl-1,4-dimethoxybenzene (DBDMB) as redox mediator and 1 M LiClO4 in propylene carbonate (G27, BASF, Independence, USA). MEs for SECM imaging were prepared by sealing a Pt wire of 25 μm specified diameter (Goodfellow GmbH, Bad Nauheim, Germany) into borosilicate glass capillaries (Hilgenberg GmbH, Malsfeld, Germany). All SECM measurements started with the polarization of the ME to +4.1 V vs. Li/Li+ causing a diffusion-limited, steady state DBDMB oxidation current at the ME. After mounting the Si electrode, the ME was approached while observing the increasing DBDMB oxidation current at the ME, which is due to the regeneration of DBDMB at the pristine, highly doped Si electrode.22 The approach was interrupted when the ME current had doubled compared to the current in the bulk solution (distance of about 5 µm). Afterwards, the ME was translated horizontally by 250 µm in x and y directions in order to prevent investigating an area potentially altered by an incidental touch between ME and Si electrode during the initial approach. After an image (Scheme 1a) of the uncharged surface (250 µm × 250 µm) had verified the absence of significant tilt and topographic features, the ME was retracted by 5000 µm. The Si electrode was connected as working electrode (ME at open circuit potential (OCP)) and potentiodynamic charging by linear sweep voltammograms (LSVs, Scheme 1b) was initiated in a range of typically 0.1 V with 20 µV s-1. The potential range of 1.4 V to 0.5 V intervals was selected such that initial SEI formation between 1.2 V and 0.7 V was included (Fig. 1d-h), but lithiation at ES < 0.5 V was avoided.27 Lithiation with the 6 ACS Paragon Plus Environment

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associated irreversible changes of the morphology was avoided here because of the complication in SECM data interpretation when topography and reactivity change concomitantly. After each charging step, the ME returned to the position, from where the first image was initiated. After a delay of 15 min for equilibration of the electrode, the identical area was scanned again (Scheme 1a). This sequence was repeated until the final potential of 0.5 V vs. Li/Li+.

Scheme 1: Sequence of (a) SECM imaging with a constant potential applied to the ME and (b) charging of the Si electrode by sweeping the potential of the Si electrode while the ME is retracted and at OCP. Schematic is not to scale.

Results and Discussion



All LSVs in Fig. 1 show an initial current decay in connection with re-establishing the external potential control of the Si electrode after the preceding imaging when the Si electrode is at OCP. After the decay, the reduction current levels towards a plateau. The low scan rate ensures a low contribution of double layer charging currents and limits hysteresis due to diffusion in the liquid electrolyte. Optimizing scan rates and delay time were critical for the conclusiveness of the obtained data: Too short delay times and too fast potential scan rates caused continuation of the SEI formation processes during the SECM experiment leading to sloped images. We hypothized that the plateau currents in different LSVs should decay after the SEI was formed and separated the Si electrode from the liquid electrolyte. Indeed, the plateau currents differ for the potential intervals. The maximum reduction current plateau in Fig. 1 occurs at 1.0 V in agreement to cyclic voltammograms for microstructured Si-electrodes with identical properties in PC.27 This also applies to the small rise of reduction currents towards the lower end of the investigated potential range. Reference 27 also provides full charge-discharge cycles of the material studied here.

Figure 1. Collected linear sweep voltammograms for potentiodynamic charging of the Si electrode at 20 µV s-1 in 5 mM DBDMB and 1 M LiClO4 mediator in propylene carbonate. The blue lines and circles are guides to the eye highlighting the plateau currents. The letters c-j refer the SECM images in Figure 2 that were recorded after the corresponding LSV.


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After each LSV, the potential control is exerted to the ME and the Si electrode is left at OCP. The image in Fig. 2a shows a maximum ME currents of approximately 12 nA and was recorded prior to the first charging LSV. The subsequent SECM images were recorded on the same region. Figure 2b shows the image after an externally potential ES of 2.0 V was applied first to the Si electrode and then swept to 1.4 V. No SEI formation should occur in this potential range. In agreement with this expectation, there are little current variation in Fig. 2b except noise and sample tilt. The images in Fig. 2c-j correspond to the potentials labeled c-j in the LSVs of Fig 1. Within the image series, only small changes occur between ES of 1.4 V and 1.1 V (Fig. 2b-e). The formation of a V-shaped region with lower ME currents in the upper right part of the imaging frame has an average ME current of about 5 nA, which is lower than in the rest of the image. However, the uniformity of the V-shaped region changes to a heterogeneous pattern with spots of very low ME currents when the final charging potential approaches the plateau with the largest reduction currents, i.e. at ES  1.0 V vs. Li/Li+. (Fig. 2f). Such growth patterns are reminiscent to a nucleation process,30 and have also been observed for electropolymerization processes31,32 and grafting of organic layers to electrodes. The reduction-induced polymerization of organic electrolyte components (e.g. of propylene carbonate) results in passivating layers on the Si electrode. It is evident that even on an almost atomically flat Si electrode, the reduction of electrolyte constitutes and the deposition of insoluble reaction products does not occur uniformly but in concentrically spreading spots. While electron transfer reactions are still proceeding fast at some parts of the Si electrode, regions of about 50 µm diameter are visible, in which electron transfer reactions are inhibited (i.e. the Si surfaces is 9 ACS Paragon Plus Environment


passivated). The growth of the regions with low ME currents (marked by red ellipses in Fig. 2f to 2i) after subsequent charging LSV are indicative for spreading pristine SEI layer. The film forming process is finally completed in the region at x > 100 µm and y > 70 µm in Fig. 2i-j. The observation of a local onset of SEI formation on a nearly atomically flat electrode is a novel finding and might be essential for the understanding of film formation on Si. Formation of organic layers often have a local onset where a critical amount of organic material must be deposited first to form a new phase which can than further grow to a film. The growth perpendicular to the electrode surface remains small if the organic layer is electronically insulating. In the present case, the lateral dimensions of incipient SEI is clearly detectable for SECM with micrometer resolution. Even smaller precursor region may exist that are beyond the current resolution of our setup.


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Figure 2. SECM images taken from an identical region of the Si electrode in 5 mM DBDMB and 1 M LiClO4 mediator in propylene carbonate. (a) Before applying external potential control to the Si electrode; (b) to (j) after LSV charging to the final potential ES (vs. Li|Li+) indicated in the figure pannels; ET = +4.1 V. During imaging the Si electrode is at OCP.



The histogram plots in Fig. 3 were constructed from the ME currents of the SECM images in Fig. 2 with a binsize of 3% of the current range of each image. They provide an overview about the development of the ME currents recorded in the entire series. The image before charging has a very high average current with most of the data points above 8 nA. After scanning ES to 1.1 V, a current decay is evident. The shape of the histograms is maintained for the next three images. When the potential of ES = 1.0 V is reached (corroborating the maximum of the reduction currents plateaus in Fig. 1 and the first indications of SEI nucleation in Fig. 2f), the overall current decreases gradually to a much lower values (0.0 – 4.0 nA) although cyclic voltammograms at the ME far away from the surface prove the unchanged state of the ME probe. This indicates a passivation of most parts of the scanned area. After scanning the Si electrode to ES = 0.9 V, there is a further significant decrease of the ME current and an increasing width of the histograms. This trend continues in the images recorded after charging to 0.8 V, 0.7 V, 0.6 V and 0.5 V indicating a nearly complete coverage of the Si electrode by a passivating SEI layer in agreement with the conclusions from the charging LSVs and the SECM images.


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Figure 3. Histograms of ME currents within SECM images. The data were extracted from the SECM images of Fig. 2.

In conclusion, SECM images, for the first time, provide clear insight into the spatiotemporal, incipient SEI formation on highly conductive, almost perfectly smooth single crystalline Si electrodes in propylene carbonate electrolytes. The film formation starts from SEI-nuclei, from which the SEI grows laterally by accumulation of electrolyte decomposition products. Different to the established notion that SEI formation occurs mainly around the potential of the film formation peak in CVs, the SECM results prove a locally heterogeneous growth within a broad potential range. Because the potential range is positive of the potential for lithiation, the observations concern mostly the organic part of the SEI. The locally heterogeneous growth of the SEI occurs even on an almost atomically smooth Si electrode, where heterogeneities in surface structure and local electron transfer rates are not expected. Author information and Notes 13 ACS Paragon Plus Environment


Corresponding Author: Gunther Wittstock, [email protected] ORCID E. dos Santos Sardinha 0000-0002-8032-7577 M. Sternad 0000-0001-9307-222X M. Wilkening 0000-0001-9706-4892 G. Wittstock 0000-0002-6884-5515 Notes The author declare no competing interests Acknowledgements The authors acknowledge the financial support from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brazil) for a “Ciência sem Fronteiras” scholarship to E.S.S. (233204/2014-8) and the donation of silicon wafers by Infineon Technology Austria. M.W. and M.S. thanks the Austrian Federal Ministry of Science, Research and Economy, and the Austrian National Foundation for Research, Technology and Development for financial support. G.W. is grateful to the Federal Ministry of Education and Research for support of SECM studies on novel battery electrodes (grant number 03XP0125C).


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References (1) Armand, M.; Tarascon, J. M. Building better batteries. Nature 2008, 451, 652–657. (2) Bruce, P. G. Energy storage beyond the horizon: Rechargeable lithium batteries. Solid State Ionics 2008, 179, 752–760. (3) Janski, R.; Fugger, M.; Forster, M.; Sorger, M.; Dunst, A.; Hanzu, I.; Sternad, M.; Wilkening, M. Lithium barrier materials for on-chip Si-based microbatteries. J. Mater. Sci.: Mater. Electron. 2017, 28, 14605–14614. (4) Besenhard, J. O.; Winter, M.; Yang, J.; Biberacher, W. Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes. J. Power Sources 1995, 54, 228–231. (5) Dunst, A.; Sternad, M.; Epp, V.; Wilkening, M. Fast Li+ Self-Diffusion in Amorphous Li–Si Electrochemically Prepared from Semiconductor Grade, Monocrystalline

Silicon:

Insights

from

Spin-Locking

Nuclear

Magnetic

Relaxometry. J. Phys. Chem. C 2015, 119, 12183–12192. (6) Obrovac, M. N.; Christensen, L. Structural Changes in Silicon Anodes during Lithium Insertion/Extraction. Electrochem. Solid-State Lett. 2004, 7, A93-A96. (7) Ma, D.; Cao, Z.; Hu, A. Si-Based Anode Materials for Li-Ion Batteries: A Mini Review. Nano-Micro Lett. 2014, 6, 347–358. (8) Vogl, U. S.; Lux, S. F.; Crumlin, E. J.; Liu, Z.; Terborg, L.; Winter, M.; Kostecki, R. The Mechanism of SEI Formation on a Single Crystal Si(100) Electrode. J. Electrochem. Soc. 2015, 162, A603-A607. (9) Peled, E. The Electrochemical Behavior of Alkali and Alkaline Earth Metals in Nonaqueous Battery Systems - The Solid Electrolyte Interphase Model. J. Electrochem. Soc. 1979, 126, 2047–2051.



(10) E. Peled, S. M. Review—SEI: Past, Present and Future. J. Electrochem. Soc. 2017, 164. (11) Tarascon, J. M.; Armand, M. Issues and challenges facing rechargeable lithium batteries. Nature 2001, 414, 359–367. (12) Aurbach, D.; Gamolsky, K.; Markovsky, B.; Gofer, Y.; Schmidt, M.; Heider, U. On the use of vinylene carbonate (VC) as an additive to electrolyte solutions for Liion batteries. Electrochim. Acta 2002, 47, 1423–1439. (13) Vetter, J.; Novák, P.; Wagner, M. R.; Veit, C.; Möller, K. C.; Besenhard, J. O.; Winter, M.; Wohlfahrt-Mehrens, M.; Vogler, C.; Hammouche, A. Ageing mechanisms in lithium-ion batteries. J. Power Sources 2005, 147, 269–281. (14) Winter, M. The solid electrolyte interphase - the most important and the least understood solid electrolyte in rechargeable Li batteries. Z. Phys. Chem. (Muenchen, Ger.) 2009, 223, 1395–1406. (15) Hur, J. I.; Smith, L. C.; Dunn, B. High Areal Energy Density 3D Lithium-Ion Microbatteries. Joule 2018, 2, 1187–1201. (16) Philippe, B.; Dedryvère, R.; Allouche, J.; Lindgren, F.; Gorgoi, M.; Rensmo, H.; Gonbeau, D.; Edström, K. Nanosilicon Electrodes for Lithium-Ion Batteries: Interfacial Mechanisms Studied by Hard and Soft X-ray Photoelectron Spectroscopy. Chem. Mater. 2012, 24, 1107–1115. (17) Seidl, L.; Martens, S.; Ma, J.; Stimming, U.; Schneider, O. In situ scanning tunneling microscopy studies of the SEI formation on graphite electrodes for Li(+)ion batteries. Nanoscale 2016, 8, 14004–14014. (18) Schwager, P.; Bülter, H.; Plettenberg, I.; Wittstock, G. Review of Local In Situ Probing Techniques for the Interfaces of Lithium-Ion and Lithium-Oxygen Batteries. Energy Technol. 2016, 4, 1472–1485. 16 ACS Paragon Plus Environment

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Page 17 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(19) Ventosa, E.; Schuhmann, W. Scanning electrochemical microscopy of Li-ion batteries. Phys. Chem. Chem. Phys. 2015, 28441. (20) Zampardi, G.; Ventosa, E.; La Mantia, F.; Schuhmann, W. In situ visualization of Li-ion intercalation and formation of the solid electrolyte interphase on TiO2 based paste electrodes using scanning electrochemical microscopy. Chem. Commun. (Cambridge, U. K.) 2013, 49, 9347–9349. (21) Bülter, H.; Peters, F.; Schwenzel, J.; Wittstock, G. Spatiotemporal Changes of the Solid Electrolyte Interphase in Lithium-Ion Batteries Detected by Scanning Electrochemical Microscopy. Angew. Chem., Int. Ed. 2014, 53, 10531–10535. (22) Bülter, H.; Peters, F.; Schwenzel, J.; Wittstock, G. Comparison of Electron Transfer Properties of the SEI on Graphite Composite and Metallic Lithium Electrodes by SECM at OCP. J. Electrochem. Soc. 2015, 162, A7024-A7036. (23) Bülter, H.; Peters, F.; Wittstock, G. Scanning Electrochemical Microscopy for the In Situ Characterization of Solid-Electrolyte Interphases: Highly Oriented Pyrolytic Graphite versus Graphite Composite. Energy Technol. 2016, 4, 1486–1494. (24) Ventosa, E.; Wilde, P.; Zinn, A.-H.; Trautmann, M.; Ludwig, A.; Schuhmann, W. Understanding surface reactivity of Si electrodes in Li-ion batteries by in operando scanning electrochemical microscopy. Chem. Commun. (Cambridge, U. K.) 2016, 52, 6825–6828. (25) Bülter, H.; Sternad, M.; dos Santos Sardinha, E.; Witt, J.; Dosche, C.; Wilkening, M.; Wittstock, G. Investigation of the Electron Transfer at Si Electrodes: Impact and Removal of the Native SiO2 Layer. J. Electrochem. Soc. 2016, 163, A504A512.



(26) Chen, J.; Buhrmester, C.; Dahn, J. R. Chemical Overcharge and Overdischarge Protection for Lithium-Ion Batteries. Electrochem. Solid-State Lett. 2005, 8, A59A62. (27) Sternad, M.; Forster, M.; Wilkening, M. The microstructure matters: Breaking down the barriers with single crystalline silicon as negative electrode in Li-ion batteries. Sci. Rep. 2016, 6, 31712. (28) Barrio, R.; Maffiotte, C.; Gandía, J. J.; Cárabe, J. Surface characterisation of wafers for silicon-heterojunction solar cells. J. Non-Cryst. Solids 2006, 352, 945–949. (29) Nunes Kirchner, C.; Hallmeier, K. H.; Szargan, R.; Raschke, T.; Radehaus, C.; Wittstock, G. Evaluation of Thin Film Titanium Nitride Electrodes for Electroanalytical Applications. Electroanalysis 2007, 19, 1023–1031. (30) Buqa, H.; Golob, P.; Winter, M.; Besenhard, J. O. Modified carbons for improved anodes in lithium ion cells. J. Power Sources 2001, 97-98, 122–125. (31) Santner, H. J.; Möller, K.-C.; Ivančo, J.; Ramsey, M. G.; Netzer, F. P.; Yamaguchi, S.; Besenhard, J. O.; Winter, M. Acrylic acid nitrile, a film-forming electrolyte component for lithium-ion batteries, which belongs to the family of additives containing vinyl groups. J. Power Sources 2003, 119-121, 368–372. (32) Santner, H. J.; Korepp, C.; Winter, M.; Besenhard, J. O.; Möller, K.-C. In-situ FTIR investigations on the reduction of vinylene electrolyte additives suitable for use in lithium-ion batteries. Anal. Bioanal. Chem. 2004, 379, 266–271.


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Nascent SEI-Surface Films on Single Crystalline Silicon Investigated

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