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publications

-- “Controlling Covalency and Anion Redox Potentials through Anion Substitution in Li-rich Chalcogenides,”

Andrew J. Martinolich, Joshua J. Zak, Seong Shik Kim, Nicholas H. Bashian, Ahamed Irshad, David N. Agyeman-Budu, S. R. Narayan, Brent C. Melot, Johanna Nelson Weker, and Kimberly A. See

submitted.

-- “Selective Formation of Pyridinic-Type Nitrogen-doped Graphene and Its Application in Lithium-Ion Battery Anodes,”

Jacob D. Bagley, Deepan Kishore Kumar, Kimberly A. See, Nai-Chang Yeh

submitted.

25. "A Super-Oxidized Radical Cationic Icosahedral Boron Cluster"

Julia M. Stauber, Josef Schwan, Xinglong Zhang, Jonathan C. Axtell, Dahee Jung, Brendon J. McNicholas, Paul H. Oyala, Andrew J. Martinolich, Jay R. Winkler, Kimberly A. See, Thomas F. Miller III, Harry B. Gray, Alexander M. Spokoyny,

J. Am. Chem. Soc. 2020, 142, 12948-12953.

https://doi.org/10.1021/jacs.0c06159

24. "Understanding the Role of Crystallographic Shear on the Electrochemical Behavior of Niobium Oxyfluorides"

Nicholas H. Bashian, Molleigh B. Preefer, JoAnna Milam-Guerrero, Joshua J. Zak, Charlotte Sendi, Suha Ahsan, Rebecca Vincent, Ralf Haiges, Kimberly A. See, Ram Seshadri, Brent C. Melot,

J. Mat. Chem. A 2020, 8, 12623-12632.

https://doi.org/10.1039/D0TA01406K

23. "Multielectron, Cation and Anion Redox in Lithium-Rich Iron Sulfide Cathodes"

Charles J. Hansen, Joshua J. Zak, Andrew J. Martinolich, Jesse S. Ko, Nicholas H. Bashian, Farnaz Kaboudvand, Anton Van der Ven, Brent C. Melot, Johanna Nelson Weker, and Kimberly A. See,

J. Am. Chem. Soc. 2020, 142, 6737-3749.

https://doi.org/10.1021/jacs.0c00909

tl;dr Two isostructural alkali-rich metal sulfides - Li2FeS2 and previously unreported LiNaFeS2 - demonstrate reversible multielectron redox (>= 1.5 electrons). We probe the charge storage mechanism and find that both cationic and anionic redox contribute. In the beginning of the charge profile, the materials undergo a deintercalation-like mechanism in which Fe2+ is oxidized to Fe2+/3+. Oxidation of Fe2+ causes the Fe and S bands to rehybridize, increasing the covalency of the Fe-S correlations and pushing the S 2p states closer to the Fermi level. Subsequent oxidation occurs on the anions, (S)2-, to form (S2)2- moieties causing loss of long-range order. The anion oxidation is clearly observed in S K-edge X-ray absorption spectroscopy.

22. "Conditioning-Free Electrolyte by Minor Addition of Mg(HMDS)2"

Seong Shik Kim, Sarah C. Bevilacqua, and Kimberly A. See,

ACS Appl. Mater. Interfaces 2020, 12, 5226-5233.

https://doi.org/10.1021/acsami.9b16710

tl;dr Addition of small concentrations of Mg(HMDS)2 reduces cathodic current associated with Al deposition in the magnesium aluminum chloride complex (MACC) electrolyte, resulting in a conditioned electrolyte on cycle 1. Such a drastic change in the electrochemistry from addition of a very small concentration of Mg(HMDS)2 suggests that the effect is localized to the electrode-electrolyte interface. Electrochemical experiments suggest that addition of Mg(HMDS)2 not only scavenges water, but also causes a secondary effect that we hypothesize is the formation of free Cl-.

21. "Dense Garnet-Type Electrolyte with Coarse Grains for Improved Air Stability and Ionic Conductivity"

Xiaomei Zeng, Andrew J. Martinolich, Kimberly A. See, and Katherine T. Faber,

J. Energy Storage 2020, 27, 101128.

https://doi.org/10.1016/j.est.2019.101128

20. "Effect of the Electrolyte Solvent on Redox Processes in Mg-S Batteries"

Sarah C. Bevilacqua, Kim H. Pham, and Kimberly A. See,

Inorg. Chem. 2019, 58, 10472-10482.

http://dx.doi.org/10.1021/acs.inorgchem.9b00891

tl;dr Mg deposition and stripping is demonstrated with a MgCl2 and AlCl3 electrolyte in a variety of ethereal solvents. The new electrolyte systems are used to systematically study solvent effects on sulfur electroreduction in Mg-S cells. Irreversible sulfur reduction is observed when Mg-S cells are prepared with the electrolytes, and the peak potential is found to vary with solvent suggesting that the electrolyte is active in the reduction mechanism.

19. "Solid State Divalent Ion Conductivity in ZnPS3"

Andrew J. Martinolich, Cheng-Wei Lee, I-Te Lu, Sarah C. Bevilacqua, Molleigh B. Preefer, Marco Bernardi, André Schleife, and Kimberly A. See,

Chem. Mater. 2019, 31, 3652-3661.

http://dx.doi.org/10.1021/acs.chemmater.9b00207

tl;dr ZnPS3 supports divalent ion conduction, Zn2+, with low activation energies (350 meV). Zn2+ diffuses via a vacancy-mediated mechanism within the metal layer. The transition state that defines the activation energy along the Zn2+ diffusion pathway involves an extension of the P-P-S bond angle in [P2S6]4-, pushing S into the van der Waals gap.

prior to Caltech

18. "Elucidating Zn and Mg Electrodeposition Mechanisms in Nonaqueous Electrolytes for Next-Generation Metal Batteries"