"Deciphering Interface Challenges in Batteries and Quantum Materials using Scanning Transmission Electron Microscopy (STEM)"
Regardless of the recent significant advancements in battery research, the full potential of batteries is often limited by interface challenges, such as sluggish ion transport, dendrite formation, and mechanical degradation during electrochemical cycling. In my presentation, I will address these challenges and the critical role of Cryogenic Scanning Transmission Electron Microscopy (STEM) in understanding interfaces in ion-based and solid-state batteries. I will explore the underlying mechanisms of lithium dendrite formation in solid electrolytes and the formation of interphase layers at electrolyte-electrode interfaces, demonstrating how low-loss Electron Energy Loss Spectroscopy (EELS) visualizes electronic structures at grain boundaries. We show that monochromated EELS can quantify ion concentration and activation energy at interfaces, shedding light on ion transport issues in solid-state systems. The presentation will conclude with a discussion on the future potential of cryogenic STEM in battery and quantum materials research, as well as our current efforts to investigate heterogeneities in 2D quantum materials using stable cryogenic STEM and EELS.