A real turn on, and off, for chemistry

Light and dark have previously been used to control distinct chemical reaction pathways but a way to switch off ground-state reactivity reversibly by shedding a little light on the reactants has been demonstrated as a unique tool that could be used to break the lower limit on how small micro-electronic components can be "printed". Hannes Houck, Filip Du Prez and Christopher Barner-Kowollik from the Queensland University of Technology, Brisbane, Karlsruhe Institute of Technology and Ghent University, have explored the possibility of a light switch for chemical reactions. "The results of our study have the potential to establish super resolution photoresists that break the diffraction barrier to print a few nanometre wide lines with visible light – a distant dream today," Barner-Kowollik says.