Unusual applications of photocatalysis: why understanding the mechanisms is essential

Understanding photochemical mechanisms can improve both plastic recycling and protection against light-induced damage. The seminar revisits acridinium-catalysed conversion of polystyrene to benzophenone, where reactive oxygen species explain the observed chemistry rather than the previously proposed pathway. It also examines unwanted flavour changes in champagne, tracing a light-induced defect to a dimeric radical-cation intermediate. These cases connect mechanistic evidence with process optimization, industrial scale-up and possible chemical protection strategies.