@article{saeed_fleischmann_kobayashi_jusys_mamontov_osti_holzapfel_song_wang_dai_et al._2024, title={Oxide Acidity Modulates Structural Transformations in Hydrogen Titanates during Electrochemical Li-Ion Insertion}, ISSN={["1520-5126"]}, DOI={10.1021/jacs.4c08063}, abstractNote={Hydrogen titanates (HTOs) form a diverse group of metastable, layered titanium oxides with an interlayer containing both water molecules and structural protons. We investigated how the chemistry of this interlayer environment influenced electrochemical Li+-insertion in a series of HTOs, H2TiyO2y+1·nH2O (y = 3, 4, and 5). We correlated the electrochemical response with the physical and chemical properties of HTOs using operando X-ray diffraction, in situ differential electrochemical mass spectroscopy, solid-state proton nuclear magnetic resonance, and quasi-elastic neutron scattering. We found that the potential for the first reduction reaction trended with the relative acidity of the structural protons. This mechanism was supported with first-principles density functional theory (DFT) calculations. We propose that the electrochemical reaction involves reduction of the structural protons to yield hydrogen gas and formation of a lithiated hydrogen titanate (H2–xLixTiyO2y+1). The hydrogen gas is confined within the HTO lattice until the titanate structure expands upon subsequent oxidation. Our work has implications for the electrochemical behavior of insertion hosts containing hydrogen and structural water molecules, where hydrogen evolution is expected at potentials below the hydrogen reduction potential and in the absence of electrolyte proton donors. This behavior is an example of electrochemical electron transfer to a nonmetal element in a metal oxide host, in analogy to anion redox.}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Saeed, Saeed and Fleischmann, Simon and Kobayashi, Takeshi and Jusys, Zenonas and Mamontov, Eugene and Osti, Naresh C. and Holzapfel, Noah P. and Song, Haohong and Wang, Tao and Dai, Sheng and et al.}, year={2024}, month={Oct} }
 @article{elmanzalawy_innocenti_zarrabeitia_peter_passerini_augustyn_fleischmann_2023, title={Mechanistic understanding of microstructure formation during synthesis of metal oxide/carbon nanocomposites}, ISSN={["2050-7496"]}, DOI={10.1039/d3ta01230a}, abstractNote={
            In situ analysis of physicochemical processes occurring during pyrolysis synthesis of a TMO/C nanocomposite, including microstructure analysis via (S)TEM. Characterization of materials as electrodes for lithium intercalation and conversion reactions.}, journal={JOURNAL OF MATERIALS CHEMISTRY A}, author={Elmanzalawy, Mennatalla and Innocenti, Alessandro and Zarrabeitia, Maider and Peter, Nicolas J. and Passerini, Stefano and Augustyn, Veronica and Fleischmann, Simon}, year={2023}, month={Jun} }
 @article{fleischmann_zhang_wang_cummings_wu_simon_gogotsi_presser_augustyn_2022, title={Continuous transition from double-layer to Faradaic charge storage in confined electrolytes}, ISSN={["2058-7546"]}, DOI={10.1038/s41560-022-00993-z}, journal={NATURE ENERGY}, author={Fleischmann, Simon and Zhang, Yuan and Wang, Xuepeng and Cummings, Peter T. and Wu, Jianzhong and Simon, Patrice and Gogotsi, Yury and Presser, Volker and Augustyn, Veronica}, year={2022}, month={Mar} }
 @article{fleischmann_spencer_augustyn_2020, title={Electrochemical Reactivity under Confinement Enabled by Molecularly Pillared 2D and Layered Materials}, volume={32}, ISSN={["1520-5002"]}, DOI={10.1021/acs.chemmater.0c00648}, abstractNote={This perspective presents an overview of how confinement can be used to tune electrochemical reactivity and the concept of using molecularly pillared 2D and layered materials to experimentally stud...}, number={8}, journal={CHEMISTRY OF MATERIALS}, author={Fleischmann, Simon and Spencer, Michael A. and Augustyn, Veronica}, year={2020}, month={Apr}, pages={3325–3334} }
 @article{wang_sun_brady_fleischmann_eldred_gao_wang_jiang_augustyn_2021, title={Fast Proton Insertion in Layered H2W2O7 via Selective Etching of an Aurivillius Phase}, volume={11}, ISSN={["1614-6840"]}, DOI={10.1002/aenm.202003335}, abstractNote={AbstractH2W2O7, a metastable material synthesized via selective etching of the Aurivillius‐related Bi2W2O9, is demonstrated as an electrode for high power proton‐based energy storage. Comprehensive structural characterization is performed to obtain a high‐fidelity crystal structure of H2W2O7 using an iterative approach that combines X‐ray diffraction, neutron pair distribution function, scanning transmission electron microscopy, Raman spectroscopy, and density functional theory modeling. Electrochemical characterization shows a capacity retention of ≈80% at 1000 mV s–1 (1.5‐s charge/discharge time) as compared to 1 mV s–1 (≈16‐min charge/discharge time) with cyclability for over 100 000 cycles. Energetics from density functional theory calculations indicate that proton storage occurs at the terminal oxygen sites within the hydrated interlayer. Last, optical micrographs collected during in situ Raman spectroscopy show reversible, multicolor electrochromism, with color changes from pale yellow to blue, purple, and last, orange as a function of proton content. These results highlight the use of selective etching of layered perovskites for the synthesis of metastable transition metal oxide materials and the use of H2W2O7 as an anode material for proton‐based energy storage or electrochromic applications.}, number={1}, journal={ADVANCED ENERGY MATERIALS}, author={Wang, Ruocun and Sun, Yangyunli and Brady, Alexander and Fleischmann, Simon and Eldred, Tim B. and Gao, Wenpei and Wang, Hsiu-Wen and Jiang, De-en and Augustyn, Veronica}, year={2021}, month={Jan} }
 @misc{fleischmann_mitchell_wang_zhan_jiang_presser_augustyn_2020, title={Pseudocapacitance: From Fundamental Understanding to High Power Energy Storage Materials}, volume={120}, ISSN={["1520-6890"]}, DOI={10.1021/acs.chemrev.0c00170}, abstractNote={There is an urgent global need for electrochemical energy storage that includes materials that can provide simultaneous high power and high energy density. One strategy to achieve this goal is with pseudocapacitive materials that take advantage of reversible surface or near-surface Faradaic reactions to store charge. This allows them to surpass the capacity limitations of electrical double-layer capacitors and the mass transfer limitations of batteries. The past decade has seen tremendous growth in the understanding of pseudocapacitance as well as materials that exhibit this phenomenon. The purpose of this Review is to examine the fundamental development of the concept of pseudocapacitance and how it came to prominence in electrochemical energy storage as well as to describe new classes of materials whose electrochemical energy storage behavior can be described as pseudocapacitive.}, number={14}, journal={CHEMICAL REVIEWS}, author={Fleischmann, Simon and Mitchell, James B. and Wang, Ruocun and Zhan, Cheng and Jiang, De-en and Presser, Volker and Augustyn, Veronica}, year={2020}, month={Jul}, pages={6738–6782} }
 @article{frank_gaensler_hieke_fleischmann_husmann_presser_scheu_2021, title={Structural and chemical characterization of MoO2/MoS2 triple-hybrid materials using electron microscopy in up to three dimensions}, volume={3}, ISSN={["2516-0230"]}, DOI={10.1039/d0na00806k}, abstractNote={In-depth characterization of MoO2/MoS2 core/shell nanoparticles within a network of carbon nanotubes gives insights into the structure of the material and also possible degradation pathways.}, number={4}, journal={NANOSCALE ADVANCES}, author={Frank, Anna and Gaensler, Thomas and Hieke, Stefan and Fleischmann, Simon and Husmann, Samantha and Presser, Volker and Scheu, Christina}, year={2021}, month={Feb}, pages={1067–1076} }
 @article{fleischmann_sun_osti_wang_mamontov_jiang_augustyn_2020, title={Interlayer Separation in Hydrogen Titanates Enables Electrochemical Proton Intercalation}, volume={8}, ISSN={["2050-7496"]}, DOI={10.1039/c9ta11098d}, abstractNote={Interlayer structural protons in H2Ti3O7 are identified as the key structural feature to enable electrochemical proton intercalation beyond the near-surface because they effectively reduce interconnections of the titanate layers.}, number={1}, journal={Journal of Materials Chemistry A}, author={Fleischmann, S. and Sun, Y. and Osti, N.C. and Wang, R. and Mamontov, E. and Jiang, D.E. and Augustyn, V.}, year={2020}, pages={412–421} }