Bright two-color halogen-dependent chemiluminescence of Eu2+ ions at the oxidation of organoaluminium compounds by oxygen in the presence of europium dihalides

[Display omitted] •New chemiluminescence of Eu2+* with a record brightness and long duration was found.•Color of Eu2+* emission, blue or green, regulated by change the anion in Eu-dihalides.•The chemiluminescence is promising as a new chemical light source and oxygen sensor. A new bright green or blue chemiluminescence (CL) caused by the emission of Eu2+* ions generated in the oxidation of organoaluminium compounds by oxygen in THF in the presence of europium dihalides have been discovered. It was found that the duration, brightness and color of CL significantly depend on the nature of the halide anion in EuHal2 and organoaluminum compound Et3Al, iBu3Al, and iBu2AlH. High brightness of CL allows to observe it even in daylight and opens up possibilities for creation new chemical light sources and sensors for detecting ultra-low oxygen concentrations.