Versatile Cryostated Optically Transparent Thin-Layer Electrochemical (OTTLE) Cell for Variable-Temperature UV-Vis/IR Spectroelectrochemical Studies

Abstract

This article describes the construction of a novel optically transparent thin-layer electrochemical (OTTLE) cell for IR and UV-Vis spectroelectrochemical experiments at variable temperature. The cell has a three-electrode set melt-sealed into a smooth polyethylene spacer which is sandwiched between two CaF2 windows. The width of this spacer (0.18–0.20 mm) defines the thickness of the thin solution layer. The whole electrode assembly is housed in a thermostated Cu block of the OTTLE cell which fits into a double-walled nitrogen-bath cryostat. The experimental setup permits relatively fast electrolysis within the tested temperature range of 295 to 173 K under strictly anaerobic conditions and protection of light-sensitive compounds. Other important merits of the cell design include lack of leakage, facile cleaning, almost negligible variation of the preset temperature, and facile manipulation in the course of the experiments. The applicability of the variable-temperature IR/UV-Vis OTTLE cell is demonstrated by stabilization of a few electrogenerated carbonyl complexes of Mn(I) and Ru(II) with 3,5-di- tert. butyl-1,2-benzo(semi)quinone (DB(S)Q) and N, N′-diisopropyl-1,4-diaza-1,3-butadiene (iPr-DAB) ligands, respectively, at appropriately low temperatures.

Ultrafast Excited State Dynamics Controlling Photochemical Isomerization of N‐Methyl‐4‐[trans‐2‐(4‐pyridyl)ethenyl]pyridinium Coordinated to a {ReI(CO)3(2,2′‐bipyridine)} Chromophore

“…IR and UV/Vis spectral changes at various temperatures were monitored spectroelectrochemically using optically transparent thin-layer electrochemical (OTTLE) cells [83][84][85] equipped with Pt minigrid working electrodes and CaF 2 windows. Thin-layer cyclic voltammograms were recorded in the course of each spectroelectrochemical run for a precise potential control and monitoring the progress of electrolysis by the decrease of the Faradaic current.…”

Origin of electronic absorption spectra of MLCT-excited and one-electron reduced 2,2′-bipyridine and 1,10-phenanthroline complexes

“…Reduction was performed in a temperature-controlled spectroelectrochemical OTTLE cell of a 0.2 mm optical path [50,51] in THF at 253 K. The electrolysis potential was carefully controlled with a PA4 potentiostat (Laboratorní přístroje, Polná, Czech Republic) to avoid high Faradaic currents. UV-Vis and IR spectra were recorded on a Scinco S3100 diode array spectrophotometer and a Bruker Vertex 70v FT-IR spectrometer, respectively.…”

Novel Complexes trans(Cl)-[Os(bpy)(CO)(CH3CN)Cl2]n (n = 0, +1; bpy = 2,2′-Bipyridine): Photo- and Electrochemical Syntheses and Comparative Study of Their Bonding and Redox Properties

“…Spectral changes in the IR ν(CO) region recorded during the reversible oxidation of complex 1 (ca. 5 ϫ 10 Ϫ3 ) to 1 ϩ in butyronitrile; electrolysis within an OTTLE cell [39] at 273 K tempted, as support from theoretical MO studies is needed for a precise description of the molecular orbitals involved.…”