(201l) Design Principles for Electrode-Electrolyte Interfaces in Energy Conversion

Designing electrochemical materials requires a deep understanding of their behavior at the electrode-electrolyte interface, which determines efficiency and device lifetime. Challenges arise in characterizing the interface and understanding mechanisms under operando processes. In this presentation, I will describe how we understand electrochemical reactions, charge transfer, and electrokinetics at the electrode-electrolyte interface in Li-ion batteries, hydrogen fuel cells, and biosensing. By developing in situ vibrational spectroscopy and electrochemical methods, we gain insights into the local structure-property relationships to enhance material and device design for stability and efficiency. First, I will elucidate the formation of the electrode-electrolyte interface (EEI) layer on Ni-rich positive electrodes in Li-ion batteries, revealed by in situ Fourier-transform infrared spectroscopy (FTIR), and demonstrate material design principles for stable battery cycling. Next, I will discuss the ion intercalation mechanism across the interface in Li-ion batteries, which governs the discharge capacity at low to moderate rates. Lastly, beyond Li-ion batteries, I apply surface-enhanced FTIR and Raman spectroscopy using plasmonic nanomaterials to broader contexts, including elucidating the mechanistic role of hydrogen bonding in fuel cell reactions, and designing electrokinetic systems for bacterial biosensing. These studies offer insights for the rational design of materials for next-generation batteries and electrochemical devices with improved efficiency and lifetime.

References:

Zhang, Y., Katayama, Y., Tatara, R., Giordano, L., Yu, Y., Fraggedakis, D., ... & Shao-Horn, Y. (2020) Revealing Electrolyte Oxidation Via Carbonate Dehydrogenation on Ni-Based Oxides in Li-Ion Batteries By In Situ Fourier Transform Infrared Spectroscopy. Energy & Environmental Science., 13(1), 183-199.

Wang, T.‡, Zhang, Y.‡, Huang, B., Cai, B., Rao, R., Giordano, L., Sun, S-G., & Shao-Horn, Y. (2021) Enhancing Oxygen Reduction Electrocatalysis by Tuning Interfacial Hydrogen Bonds. Nature Catalysis. 4, 753–762.