Professional Education

  • PhD, Illinois Institute of Technology, Materials Science (2023)
  • MS, Federal University of Pernambuco, Materials Science (2018)
  • BS, Federal University of Pernambuco, Materials Engineering (2016)

Stanford Advisors

Contact

  • Academic
    omarques@stanford.edu
    University - Scholar Department: SLAC National Accelerator Laboratory Position: Postdoctoral Scholar

Additional Info

  • Mail Code: 0210

All Publications

  • Impact of the d0transition metal on local structural transformations in disordered rock salt cathodes. Chemical science Li, T., Marques, O., Geraci, T. S., Lawrence, E. A., Zohar, A., Liu, J., Avoka, E., Navrotsky, A., Nelson Weker, J., Clement, R. J. 2025

    Abstract

    Although it is widely accepted that the long-range (average) crystal structure plays a critical role in determining the electrochemical performance of battery materials, the relationship between local structural features and electrochemical performance is rarely studied. Disordered rock salt oxides (DRX), which have become serious contenders for next generation Li-ion electrode materials, provide an ideal platform for exploring correlations between local structure and electrochemical performance as they exhibit a simple face-centered cubic structure and combine long-range disorder and short-range order on the cation sublattice. This work examines the Li1.1Mn0.7Zr0.2-x Ti x O2 series of DRX cathodes and investigates the links between local structure rearrangements and capacity activation. The end-member Li1.1Mn0.7Zr0.2O2 compound exhibits a low capacity in the as-synthesized state, attributed to unfavorable short-range order that hinders Li-ion transport, yet its capacity increases seven-fold, from 20 to 140 mAh g-1, after chemical delithiation followed by a 400 °C heat treatment. Capacity activation is associated with the appearance of local spinel-like structural features that depart from the short-range order originally present in the material, without significant change to the bulk composition and average crystal structure. Investigation of a series of Li1.1Mn0.7Zr0.2-x Ti x O2 (x ≤ 0.2) DRX compounds reveals that the correlation length of the spinel-like ordering that emerges during the heat treatment strongly depends on the Zr:Ti ratio. Yet, dramatic capacity activation and electrochemical (pseudo-)plateaus reminiscent of Mn-based spinel cathodes are observed for all compounds irrespective of the size of the ordered domains. To explain this phenomenon, we propose that the DRX phase undergoes a complete transformation to a spinel-like domain structure, which improves bulk Li-ion transport regardless of domain size.

    View details for DOI 10.1039/d5sc06959a

    View details for PubMedID 41235074

  • Alternative Solid-State Synthesis Route for Highly Fluorinated Disordered Rock-Salt Cathode Materials for High-Energy Lithium-Ion Batteries ADVANCED ENERGY MATERIALS Avvaru, V., Li, T., Lee, G., Byeon, Y., Koirala, K., Marques, O., Rinkel, B. L. D., Fu, Y., Milsted, D., Jeong, S., Szymanski, N. J., Kunz, M., Babbe, F., Lee, E., Battaglia, V., McCloskey, B. D., Weker, J., Wang, C., Yang, W., Clement, R. J., Kim, H. 2025; 15 (28)

    View details for DOI 10.1002/aenm.202500492

    View details for Web of Science ID 001535045400002

  • Reaction Mechanism of the Synthesis of a Disordered Rock Salt Cathode Material CHEMISTRY OF MATERIALS Liang, Z., Marques, O., Mellone, O., Masina, S. M., Cao, C. L., Sokaras, D., Weker, J., Stone, K. H. 2025

    View details for DOI 10.1021/acs.chemmater.4c03071

    View details for Web of Science ID 001500035400001

  • Structural modeling of high-entropy oxides battery anodes using x-ray absorption spectroscopy JOURNAL OF APPLIED PHYSICS Marques, O. J., Segre, C. U. 2024; 135 (22)

    View details for DOI 10.1063/5.0206316

    View details for Web of Science ID 001244474600005