title: In Situ Mass Spectrometric Monitoring of the Dynamic Electrochemical Process at the Electrode-Electrolyte Interface: a SIMS Approach.
abstract: The in situ molecular characterization of reaction intermediates and products at electrode-electrolyte interfaces is central to mechanistic studies of complex electrochemical processes, yet a great challenge. The coupling of electrochemistry (EC) and mass spectrometry (MS) has seen rapid development and found broad applicability in tackling challenges in analytical and bioanalytical chemistry. However, few truly in situ and real-time EC-MS studies have been reported at electrode-electrolyte interfaces. An innovative EC-MS coupling method named in situ liquid secondary ion mass spectrometry (SIMS) was recently developed by combining SIMS with a vacuum compatible microfluidic electrochemical device. Using this novel capability, we report the first in situ elucidation of the electro-oxidation mechanism of a biologically significant organic compound, ascorbic acid (AA), at the electrode-electrolyte interface. The short-lived radical intermediate was successfully captured, which had not been detected directly before. Moreover, we demonstrated the power of this new technique in real-time monitoring of the formation and dynamic evolution of electrical double layers at the electrode-electrolyte interface. This work suggests further promising applications of in situ liquid SIMS in studying more complex chemical and biological events at the electrode-electrolyte interface.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, National Centre for Mass Spectrometry in Beijing, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Zhaoying
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, National Centre for Mass Spectrometry in Beijing, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Bingwen
authors.initials: B
authors.lastname: Liu
authors.affiliation: Beijing National Laboratory for Molecular Sciences, National Centre for Mass Spectrometry in Beijing, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Kui
authors.initials: K
authors.lastname: Wu
authors.forename: Suntharampillai
authors.initials: S
authors.lastname: Thevuthasan
authors.forename: Donald R
authors.identifier: 0000-0003-0875-5961
authors.initials: DR
authors.lastname: Baer
authors.forename: Zihua
authors.identifier: 0000-0001-5770-8462
authors.initials: Z
authors.lastname: Zhu
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Yu
authors.affiliation: Beijing National Laboratory for Molecular Sciences, National Centre for Mass Spectrometry in Beijing, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Fuyi
authors.initials: F
authors.lastname: Wang
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D004573:Electrolytes / Q000737:chemistry; D046210:Microfluidic Analytical Techniques; D018629:Spectrometry, Mass, Secondary Ion
chemical_list: D004573:Electrolytes; D001205:Ascorbic Acid