“…The elastic-ML materials are being strongly anticipated as a promising alternative to the fluorescent materials for stress sensing, , anticounterfeiting, , onsite infrastructure diagnosis, bioimaging, flexible optoelectronics, and biomimetic multifunctional E-skins , because elastic-ML materials tend to produce even brighter and more reproducible ML than fracto-ML materials . Up to now, a series of elastic ML materials have been proposed by doping transition metal ions (e.g., Mn 2+ , Cu 2+ ) or rare-earth ions (e.g., Eu 2+ , Pr 3+ , Sm 3+ , and Nd 3+ ) into piezoelectric host materials, such as ZnS/Mn 2+ , , ZnS/Cu 2+ , CaZnOS/Mn 2+ , , SrAl 2 O 4 /Eu 2+ , BaSi 2 O 2 N 2 /Eu 2+ , , Ca 2 Al 2 SiO 7 /Eu 3+ , LiNbO 3 /Pr 3+ , CaZr(PO 4 ) 2 /Mn 2+ , and so on. Unfortunately, there are still several critical bottlenecks need to be solved for the goal of achieving highly efficient ML materials.…”