In April 2023, we started with our 4-year-project reaCtor. The ambitious goal: to develop and demonstrate an innovative concept for photo-flow-chemistry towards a sustainable chemical industry with drastically reduced greenhouse gas emissions. Our concept involves fabricating microreactors inside hollow specialty fibres. Light from a single light source is guided in the ring core of the fibre and excites plasmonic nanoparticles located on the reaction volume wall, which effic