A versatile method for the determination of photochemical quantum yields via online UV-Vis spectroscopy. Issue 5 (1st May 2018)

• Record Type: Journal Article
• Authors: Stadler, Eduard; Eibel, Anna; Fast, David; Freißmuth, Hilde; Holly, Christian; Wiech, Mathias; Moszner, Norbert; Gescheidt, Georg
• Is Part Of: Photochemical & photobiological sciences. Volume 17:Issue 5(2018)
• Page Start: 660
• Page End: 669
• Publication Date: 2018-05-01
• Subjects: Photochemistry -- Periodicals; Photobiology -- Periodicals; 541.35
• DOI: 10.1039/c7pp00401j
• Languages: English
• ISSNs: 1474-905X

Abstract

Abstract : On-line UV-Vis monitoring of photochemical reactions driven by LEDs allows the straightforward determination of quantum yields. Abstract : We have developed a simple method for determining the quantum yields of photo-induced reactions. Our setup features a fibre coupled UV-Vis spectrometer, LED irradiation sources, and a calibrated spectrophotometer for precise measurements of the LED photon flux. The initial slope in time-resolved absorbance profiles provides the quantum yield. We show the feasibility of our methodology for the kinetic analysis of photochemical reactions and quantum yield determination. The typical chemical actinometers, ferrioxalate and ortho -nitrobenzaldehyde, as well as riboflavin, a spiro-compound, phosphorus- and germanium-based photoinitiators for radical polymerizations and the frequently utilized photo-switch azobenzene serve as paradigms. The excellent agreement of our results with published data demonstrates the high potential of the proposed method as a convenient alternative to the time-consuming chemical actinometry.