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3. Electrochemical trapping of metastable Mn3+ ions for activation of MnO2 oxygen evolution catalysts

Author

Morgan Chan, Zamyla, Kitchaev, Daniil A, Nelson Weker, Johanna, Schnedermann, Christoph, Lim, Kipil, Ceder, Gerbrand, Tumas, William, Toney, Michael F, and Nocera, Daniel G

Subjects
Engineering, Macromolecular and Materials Chemistry, Materials Engineering, Chemical Sciences, manganese oxide, polymorph, water splitting, catalysis, renewable energy storage
Abstract

Electrodeposited manganese oxide films are promising catalysts for promoting the oxygen evolution reaction (OER), especially in acidic solutions. The activity of these catalysts is known to be enhanced by the introduction of Mn3+ We present in situ electrochemical and X-ray absorption spectroscopic studies, which reveal that Mn3+ may be introduced into MnO2 by an electrochemically induced comproportionation reaction with Mn2+ and that Mn3+ persists in OER active films. Extended X-ray absorption fine structure (EXAFS) spectra of the Mn3+-activated films indicate a decrease in the Mn-O coordination number, and Raman microspectroscopy reveals the presence of distorted Mn-O environments. Computational studies show that Mn3+ is kinetically trapped in tetrahedral sites and in a fully oxidized structure, consistent with the reduction of coordination number observed in EXAFS. Although in a reduced state, computation shows that Mn3+ states are stabilized relative to those of oxygen and that the highest occupied molecular orbital (HOMO) is thus dominated by oxygen states. Furthermore, the Mn3+(Td) induces local strain on the oxide sublattice as observed in Raman spectra and results in a reduced gap between the HOMO and the lowest unoccupied molecular orbital (LUMO). The confluence of a reduced HOMO-LUMO gap and oxygen-based HOMO results in the facilitation of OER on the application of anodic potentials to the δ-MnO2 polymorph incorporating Mn3+ ions.

Published
2018

5. TomoPyUI: a user‐friendly tool for rapid tomography alignment and reconstruction.

Author

Welborn, Samuel S., Preefer, Molleigh B., and Nelson Weker, Johanna

Subjects
TOMOGRAPHY, IMAGE reconstruction algorithms, USER interfaces, DATA warehousing, PYTHON programming language, METADATA, PIPELINE inspection, INTEGRATED software, ELECTRONIC data processing
Abstract

The management and processing of synchrotron and neutron computed tomography data can be a complex, labor‐intensive and unstructured process. Users devote substantial time to both manually processing their data (i.e. organizing data/metadata, applying image filters etc.) and waiting for the computation of iterative alignment and reconstruction algorithms to finish. In this work, we present a solution to these problems: TomoPyUI, a user interface for the well known tomography data processing package TomoPy. This highly visual Python software package guides the user through the tomography processing pipeline from data import, preprocessing, alignment and finally to 3D volume reconstruction. The TomoPyUI systematic intermediate data and metadata storage system improves organization, and the inspection and manipulation tools (built within the application) help to avoid interrupted workflows. Notably, TomoPyUI operates entirely within a Jupyter environment. Herein, we provide a summary of these key features of TomoPyUI, along with an overview of the tomography processing pipeline, a discussion of the landscape of existing tomography processing software and the purpose of TomoPyUI, and a demonstration of its capabilities for real tomography data collected at SSRL beamline 6‐2c. [ABSTRACT FROM AUTHOR]

Published
2024
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9. Effect of Metal dBand Position on Anion Redox in Alkali-Rich Sulfides

Author

Kim, Seong Shik, Agyeman-Budu, David N., Zak, Joshua J., Andrews, Jessica L., Li, Jonathan, Melot, Brent C., Nelson Weker, Johanna, and See, Kimberly A.

Abstract

New energy storage methods are emerging to increase the energy density of state-of-the-art battery systems beyond conventional intercalation electrode materials. For instance, employing anion redox can yield higher capacities compared with transition metal redox alone. Anion redox in sulfides has been recognized since the early days of rechargeable battery research. Here, we study the effect of d–poverlap in controlling anion redox by shifting the metal dband position relative to the S pband. We aim to determine the effect of shifting the dband position on the electronic structure and, ultimately, on charge compensation. Two isostructural sulfides LiNaFeS2and LiNaCoS2are directly compared to the hypothesis that the Co material should yield more covalent metal–anion bonds. LiNaCoS2exhibits a multielectron capacity of ≥1.7 electrons per formula unit, but despite the lowered Co dband, the voltage of anion redox is close to that of LiNaFeS2. Interestingly, the material suffers from rapid capacity fade. Through a combination of solid-state nuclear magnetic resonance spectroscopy, Co and S X-ray absorption spectroscopy, X-ray diffraction, and partial density of states calculations, we demonstrate that oxidation of S nonbonding pstates to S22–occurs in early states of charge, which leads to an irreversible phase transition. We conclude that the lower energy of Co dbands increases their overlap with S pbands while maintaining S nonbonding pstates at the same higher energy level, thus causing no alteration in the oxidation potential. Further, the higher crystal field stabilization energy for octahedral coordination over tetrahedral coordination is proposed to cause the irreversible phase transition in LiNaCoS2.

Published
2024
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14. Simultaneous neutron and X-ray tomography for visualization of graphite electrode degradation in fast-charged lithium-ion batteries

Author

Yusuf, Maha, primary, LaManna, Jacob M., additional, Paul, Partha P., additional, Agyeman-Budu, David N., additional, Cao, Chuntian, additional, Dunlop, Alison R., additional, Jansen, Andrew N., additional, Polzin, Bryant J., additional, Trask, Stephen E., additional, Tanim, Tanvir R., additional, Dufek, Eric J., additional, Thampy, Vivek, additional, Steinrück, Hans-Georg, additional, Toney, Michael F., additional, and Nelson Weker, Johanna, additional

Published
2023
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18. Simultaneous neutron and X-ray tomography for visualization of graphite electrode degradation in fast-charged lithium-ion batteries

Author

Yusuf, Maha, primary, LaManna, Jacob M., additional, Paul, Partha P., additional, Agyeman-Budu, David N., additional, Cao, Chuntian, additional, Dunlop, Alison R., additional, Jansen, Andrew N., additional, Polzin, Bryant J., additional, Trask, Stephen E., additional, Tanim, Tanvir R., additional, Dufek, Eric J., additional, Thampy, Vivek, additional, Steinrück, Hans-Georg, additional, Toney, Michael F., additional, and Nelson Weker, Johanna, additional

Published
2022
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19. Melt-Pool Dynamics and Microstructure of Mg Alloy WE43 under Laser Powder Bed Fusion Additive Manufacturing Conditions

Author

Soderlind, Julie, primary, Martin, Aiden A., additional, Calta, Nicholas P., additional, DePond, Philip J., additional, Wang, Jenny, additional, Vrancken, Bey, additional, Schäublin, Robin E., additional, Basu, Indranil, additional, Thampy, Vivek, additional, Fong, Anthony Y., additional, Kiss, Andrew M., additional, Berry, Joel M., additional, Perron, Aurélien, additional, Nelson Weker, Johanna, additional, Stone, Kevin H., additional, Tassone, Christopher J., additional, Toney, Michael F., additional, Van Buuren, Anthony, additional, Löffler, Jörg F., additional, Risbud, Subhash H., additional, and Matthews, Manyalibo J., additional

Published
2022
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22. Promoting Reversibility of Multielectron Redox in Alkali-Rich Sulfide Cathodes through Cryomilling

Author

Kim, Seong Shik, Agyeman-Budu, David N., Zak, Joshua J., Dawson, Andrew, Yan, Qizhang, Cabán-Acevedo, Miguel, Wiaderek, Kamila M., Yakovenko, Andrey A., Yao, Yiyi, Irshad, Ahamed, Narayan, Sri R., Luo, Jian, Nelson Weker, Johanna, Tolbert, Sarah H., See, Kimberly A., Kim, Seong Shik, Agyeman-Budu, David N., Zak, Joshua J., Dawson, Andrew, Yan, Qizhang, Cabán-Acevedo, Miguel, Wiaderek, Kamila M., Yakovenko, Andrey A., Yao, Yiyi, Irshad, Ahamed, Narayan, Sri R., Luo, Jian, Nelson Weker, Johanna, Tolbert, Sarah H., and See, Kimberly A.

Abstract

Conventional cathodes for Li-ion batteries (LIBs) are reaching their theoretical capacity limits. One way to meet the growing demands for high-capacity LIBs is by developing so-called Li-rich cathode materials that greatly benefit from additional capacities from anionic moieties in the structure. Li-rich materials are intrinsically subject to higher degrees of (de)intercalation, leaving the particles more prone to fractures and thus rapid capacity fade. Alkali-rich LiNaFeS₂ reversibly cycles with capacities exceeding 300 mAh g⁻¹, but its capacity fades faster than an isostructural material Li₂FeS₂. Using synchrotron-based transmission X-ray microscopy (TXM), we demonstrate that the capacity fade of LiNaFeS₂ stems from particle fractures in the first charge cycle. We improve the cycling performance of LiNaFeS₂ by means of cryomilling, which enhances capacity retention at cycle 50 by 76%. Through crystallographic and morphological characterization techniques, we confirm that cryomilling not only decreases particle and crystallite size while increasing microstrain but also prevents particles from fracturing. Cryomilling is a powerful tool to engineer nanoscale battery materials, and TXM allows the direct observation of morphological changes of the particles, which can be leveraged to develop next-generation cathode materials for LIBs.

Published
2022

24. Room-Temperature Electrochemical Fluoride (De)insertion into CsMnFeF6

Author

Andrews, Jessica L., primary, McClure, Eric T., additional, Jew, Kenneth K., additional, Preefer, Molleigh B., additional, Irshad, Ahamed, additional, Lertola, Matthew J., additional, Robertson, Daniel D., additional, Salamat, Charlene Z., additional, Brady, Michael J., additional, Piper, Louis F. J., additional, Tolbert, Sarah H., additional, Nelson Weker, Johanna, additional, Chmelka, Bradley F., additional, Dunn, Bruce S., additional, Narayan, Sri R., additional, West, William C., additional, and Melot, Brent C., additional

Published
2022
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25. Room Temperature Electrochemical Fluoride (De)Insertion into the Defect Pyrochlore CsMnFeF6

Author

Andrews, Jessica, primary, McClure, Eric, additional, Jew, Kenneth, additional, Preefer, Molleigh, additional, Irshad, Ahamed, additional, Lertola, Matthew, additional, Robertson, Daniel, additional, Salamat, Charlene, additional, Brady, Michael, additional, Piper, Louis, additional, Tolbert, Sarah, additional, Nelson Weker, Johanna, additional, Chmelka, Brad, additional, Dunn, Bruce, additional, Narayan, Sri, additional, West, William, additional, and Melot, Brent, additional

Published
2022
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26. Promoting Reversibility of Multielectron Redox in Alkali-Rich Sulfide Cathodes through Cryomilling

Author

Kim, Seong Shik, primary, Agyeman-Budu, David N., additional, Zak, Joshua J., additional, Dawson, Andrew, additional, Yan, Qizhang, additional, Cában-Acevedo, Miguel, additional, Wiaderek, Kamila M., additional, Yakovenko, Andrey A., additional, Yao, Yiyi, additional, Irshad, Ahamed, additional, Narayan, Sri R., additional, Luo, Jian, additional, Nelson Weker, Johanna, additional, Tolbert, Sarah H., additional, and See, Kimberly A., additional

Published
2022
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28. Using In Situ High-Energy X-ray Diffraction to Quantify Electrode Behavior of Li-Ion Batteries from Extreme Fast Charging

Author

Paul, Partha P., primary, Cao, Chuntian, additional, Thampy, Vivek, additional, Steinrück, Hans-Georg, additional, Tanim, Tanvir R., additional, Dunlop, Alison R., additional, Trask, Stephen E., additional, Jansen, Andrew N., additional, Dufek, Eric J., additional, Nelson Weker, Johanna, additional, and Toney, Michael F., additional

Published
2021
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31. Room-Temperature Electrochemical Fluoride (De)insertion into CsMnFeF6.

Author

Andrews, Jessica L., McClure, Eric T., Jew, Kenneth K., Preefer, Molleigh B., Irshad, Ahamed, Lertola, Matthew J., Robertson, Daniel D., Salamat, Charlene Z., Brady, Michael J., Piper, Louis F. J., Tolbert, Sarah H., Nelson Weker, Johanna, Chmelka, Bradley F., Dunn, Bruce S., Narayan, Sri R., West, William C., and Melot, Brent C.

Published
2022
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32. A Review of Existing and Emerging Methods for Lithium Detection and Characterization in Li‐Ion and Li‐Metal Batteries

Author

Paul, Partha P., primary, McShane, Eric J., additional, Colclasure, Andrew M., additional, Balsara, Nitash, additional, Brown, David E., additional, Cao, Chuntian, additional, Chen, Bor‐Rong, additional, Chinnam, Parameswara R., additional, Cui, Yi, additional, Dufek, Eric J., additional, Finegan, Donal P., additional, Gillard, Samuel, additional, Huang, Wenxiao, additional, Konz, Zachary M., additional, Kostecki, Robert, additional, Liu, Fang, additional, Lubner, Sean, additional, Prasher, Ravi, additional, Preefer, Molleigh B., additional, Qian, Ji, additional, Rodrigues, Marco‐Tulio Fonseca, additional, Schnabel, Manuel, additional, Son, Seoung‐Bum, additional, Srinivasan, Venkat, additional, Steinrück, Hans‐Georg, additional, Tanim, Tanvir R., additional, Toney, Michael F., additional, Tong, Wei, additional, Usseglio‐Viretta, Francois, additional, Wan, Jiayu, additional, Yusuf, Maha, additional, McCloskey, Bryan D., additional, and Nelson Weker, Johanna, additional

Published
2021
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33. Quantification of heterogeneous, irreversible lithium plating in extreme fast charging of lithium-ion batteries

Author

Paul, Partha P., primary, Thampy, Vivek, additional, Cao, Chuntian, additional, Steinrück, Hans-Georg, additional, Tanim, Tanvir R., additional, Dunlop, Alison R., additional, Dufek, Eric J., additional, Trask, Stephen E., additional, Jansen, Andrew N., additional, Toney, Michael F., additional, and Nelson Weker, Johanna, additional

Published
2021
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42. Laser‐Induced Keyhole Defect Dynamics during Metal Additive Manufacturing

Author

Kiss, Andrew M., primary, Fong, Anthony Y., additional, Calta, Nicholas P., additional, Thampy, Vivek, additional, Martin, Aiden A., additional, Depond, Philip J., additional, Wang, Jenny, additional, Matthews, Manyalibo J., additional, Ott, Ryan T., additional, Tassone, Christopher J., additional, Stone, Kevin H., additional, Kramer, Matthew J., additional, van Buuren, Anthony, additional, Toney, Michael F., additional, and Nelson Weker, Johanna, additional

Published
2019
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45. NASICON Na3V2(PO4)3Enables Quasi-Two-Stage Na+and Zn2+Intercalation for Multivalent Zinc Batteries

Author

Ko, Jesse S., Paul, Partha P., Wan, Gang, Seitzman, Natalie, DeBlock, Ryan Henry, Dunn, Bruce S., Toney, Michael F., and Nelson Weker, Johanna

Abstract

Identifying positive electrode materials capable of reversible multivalent electrochemistry in electrolytes containing divalent ions such as Mg2+, Ca2+, and Zn2+at high operating potentials remains an ongoing challenge in “beyond lithium-ion” research. Herein, we explore the Zn2+charge-storage mechanism of a vanadium-based Na+superionic conductor (NASICON), Na3V2(PO4)3. By using X-ray synchrotron techniques to unravel potential-dependent structure–property relationships, we ascribe the reversible electrochemical behavior of Na3V2(PO4)3to a quasi-two-stage intercalation process that involves both Na+and Zn2+. Initial charging of Na3V2(PO4)3leads to a Na+-extracted phase corresponding to NaV2(PO4)3, whereas subsequent discharge results predominantly in Na+intercalation followed by Zn2+intercalation. Operando X-ray diffraction of Na3V2(PO4)3was used to study the phase changes associated with the first charge/discharge process, and ex situ measurements were used to precisely link the changes in the crystal structure to a quasi-two-stage intercalation of Na+and Zn2+. The corresponding changes in the V-oxidation state, V-O coordination, and the presence of Zn2+were confirmed by X-ray absorption spectroscopy. The results of this work present a comprehensive understanding of the charge-storage properties for a well-established NASICON structure that confers both the high capacity (∼100 mA h g–1) and high potential (1.35 and 1.1 V vs Zn/Zn2+).

Published
2020
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46. Electrochemically-Formed Disordered Rock Salt ω-LixV9Mo6O40as a Fast-Charging Li-Ion Electrode Material

Author

Robertson, Daniel D., Salamat, Charlene Z., Pe, David J., Cumberbatch, Helen, Agyeman-Budu, David N., Nelson Weker, Johanna, and Tolbert, Sarah H.

Abstract

Electrochemically-formed disordered rock salt compounds are an emerging class of Li-ion electrode materials for fast-charging energy storage. However, the specific factors that govern the formation process and the resulting charge storage performance are not well understood. Here, we characterize the transformation mechanism and charge storage properties of an electrochemically-formed disordered rock salt from V9Mo6O40(VMO). The crystal structure of VMO has similar motifs to that of α-V2O5, a well-studied analogue, but VMO has less mechanical flexibility due to additional corner-sharing octahedra in its structure. As a result, VMO undergoes a single-step transformation pathway, which we characterize through operando X-ray diffraction, and forms an unusual highly distorted lamellar microstructure, as we show with high-resolution transmission electron microscopy. The resulting LixVMO material shows fast charging and other electrochemical characteristics and performance typical of many nanomaterials, even though the material is composed of relatively large particles.

Published
2024
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