TY - JOUR
T1 - A Deep Insight into the Microscopic Dynamics of the Electrode-Electrolyte Interface under Extreme Operating Conditions
AU - Yuan, Rui
AU - Jiao, Handong
AU - Du, Xueyan
AU - Li, Leyang
AU - Liu, Qiang
AU - Jiao, Shuqiang
N1 - Publisher Copyright:
© 2025 American Chemical Society.
PY - 2025
Y1 - 2025
N2 - Understanding the interfacial dynamics during operation is critical for electrochemistry to make great advancements. However, breakthroughs on this topic under extreme conditions are very scarce. Here, as an example, we employ operando Raman spectroscopy to decode the interfacial dynamics of titanium electrolysis using a tailored instrument. Direct spectral evidence not only confirms the two-step reduction pathway and the key intermediate (TiF52-) in molten fluorides with high-temperature and strong-corrosion conditions but also unravels the origins of the undesirable shuttling effect of TiF52-, which are the sluggish reduction kinetics and outward diffusion behavior of TiF52-. Moreover, an insightful atomic scenario of the electric double layer (EDL) under varied potentials has been established. These quantitative understandings guide us to design economical-feasible regulation protocols─the rational combination of a high-concentration, low-valence Ti-ion electrolyte with appropriate applied potential. Impressively, the current efficiency is greatly promoted from 27.7 to 81.8% using our proposed protocols. Finally, this work also demonstrates a bottom-up technological research paradigm for extreme electrochemistry based on mechanism insights rather than phenomenological findings, which will accelerate the advancement of extreme electrochemistry.
AB - Understanding the interfacial dynamics during operation is critical for electrochemistry to make great advancements. However, breakthroughs on this topic under extreme conditions are very scarce. Here, as an example, we employ operando Raman spectroscopy to decode the interfacial dynamics of titanium electrolysis using a tailored instrument. Direct spectral evidence not only confirms the two-step reduction pathway and the key intermediate (TiF52-) in molten fluorides with high-temperature and strong-corrosion conditions but also unravels the origins of the undesirable shuttling effect of TiF52-, which are the sluggish reduction kinetics and outward diffusion behavior of TiF52-. Moreover, an insightful atomic scenario of the electric double layer (EDL) under varied potentials has been established. These quantitative understandings guide us to design economical-feasible regulation protocols─the rational combination of a high-concentration, low-valence Ti-ion electrolyte with appropriate applied potential. Impressively, the current efficiency is greatly promoted from 27.7 to 81.8% using our proposed protocols. Finally, this work also demonstrates a bottom-up technological research paradigm for extreme electrochemistry based on mechanism insights rather than phenomenological findings, which will accelerate the advancement of extreme electrochemistry.
KW - dynamic evolution
KW - extreme electrochemistry
KW - interfacial dynamics
KW - operando Raman spectroscopy
KW - side reactions
UR - http://www.scopus.com/inward/record.url?scp=85215606071&partnerID=8YFLogxK
U2 - 10.1021/acsnano.4c15336
DO - 10.1021/acsnano.4c15336
M3 - Article
AN - SCOPUS:85215606071
SN - 1936-0851
JO - ACS Nano
JF - ACS Nano
ER -