Synthesis of mechanical responsive carbon dots with fluorescence enhancement

Mechanical responsive carbon dots (CDs) is a rising star in the family of carbon materials. However, high pressure devices are essential for observing mechanical responses of carbon dots, but they limit the widespread application of mechanical responsive CDs. Two kinds of CDs were prepared using pyrene derivative (pyrene-l-butyric acid, PyBA) as carbon source, and had fluorescence enhancement via simply grinding. An apparent 20-30 times emission enhancement can be observed after the treatment of grinding because of CDs packed structure and morphology changes. To the best of our knownledge, it is the first example of mechanical responsive CDs with fluorescence enhancement without the stimulation of any complex pressure instrumentation. This simple approach could be extended to other carbon sources with pi-conjugated structure for building new intelligentized CDs, and provide new routes for the applications of CDs toward mechanical sensing. (C) 2019 Elsevier Inc. All rights reserved.