Mass spectrometric detection of fleeting neutral intermediates generated in electrochemical reactions

Abstract

Towards the goal of on-line monitoring the transient neutral intermediates during electrochemical reactions, an electrochemistry-neutral reionization-mass spectrometry (EC-NR-MS) technique was developed in this work. The EC-NR setup consisted of a...

Host‐guest tuning of the CO2 reduction activity of an iron porphyrin cage

“…In order to get a deeper insight into the host-guest chemistry of the cage catalyst and into the mechanism of the CO 2 reduction reaction, we studied the intermediates in the electrochemical reaction by electrospray ionization mass spectrometry (ESI-MS). 37 Transferring the intermediates by electrospray ionization into a mass spectrometer is a challenging task, [38][39][40] because these intermediates are formed at the cathode and presumably are short-lived and thus extremely low abundant in solution. 41 In addition, the reduced reactive species can be oxidized and thus be destroyed during the electrospray ionization process.…”

Insights into electrochemiluminescence dynamics by synchronizing real-time electrical, luminescence, and mass spectrometric measurements

“…Furthermore, by treating ECL as a unique EC process, researchers have also identied several short-lived radicals and intermediates (typically TPrAc + , TPrAc, and Ru(bpy) 3 + ) previously speculated to participate in ECL pathways by ultrafast in situ MS characterization. [26][27][28] Despite excellent temporal resolution for a MS snapshot of a chemical transformation in ECL, dynamic correlation between chemical change and luminescence with respect to applied voltage at the EEI was usually neglected. Unlike common EC reactions, ECL involves more complicated reaction networks in terms of electron transfer, chemical transformation, and energy level transition, 29,30 underlining the necessity and signicance of simultaneously tracking redox current, labile electrogenerated species, and luminescence behavior in ECL mechanism studies.…”

Interfacial Extraction to Trap and Characterize the Criegee Intermediates from Phospholipid Ozonolysis

“…The above conclusion was further supported by scavenging CIs using 5,5-dimethyl-pyrroline N -oxide (DMPO), widely used for radical identification. ,− Cycloaddition of the 1,3-dipoles of CIs and DMPO gives birth to a six-atom heterocycle nonradical adduct (DMPO-CI) . The reaction scheme is shown in Figure S10.…”

“…The inner tube (O.D., 363 μm; I.D., 220 μm) was recessed inside the outer tube with ∼0.5 mm to guarantee efficient extraction of the products/intermediates. The extracted species at/near the droplet surface were further transferred using the Venturi effect through the inner tube to a homemade sprayer, similar to that used in sonic spray, − and subsequently transferred to the mass spectrometer for analysis. The nebulizing gas functioned as nebulization for ionization and also as the force driving the products/intermediates from the droplet surface to the sprayer.…”