Synthesis and surface chemistry of mechanoluminescent nanocrystals for timely detection of damage

Fibre-reinforced polymers exhibit a high strength to weight ratio. Therefore, they fit in the growing trend towards more sustainable technologies, as the focus there also lies on saving energy by using lighter materials, next to the generation of electrical power using for example wind energy. However, within these composites, damage initiates very early in time and grows gradually. In this context, mechanoluminescent ZnS:Mn/ZnS core/shell nanocrystals emerge as interesting materials for continuous damage monitoring, which is key for operational reliability and human safety. We focus on simple, full yield, one-pot-synthesis of ZnS:Mn/ZnS doped core/shell nanocrystals with total control over core and shell size, and doping concentration, making use of thioureas. Using rational ligand exchange reactions, these highly luminescent nanocrystals can be stabilized in various solvent systems, including a polymer matrix, creating high quality nanocomposites.