Perovskite-based photoluminescent detection of lead particles in gunshot residue.

Gunshot residue (GSR) analysis is crucial for forensic investigations of shooting incidents, but current methods are time-consuming, laborious, and provide limited spatial resolution. We introduce photoluminescent lead analysis (PL-Pb) for instant high-resolution GSR detection. Lead particles in GSR react into lead halide perovskite semiconductors that emit bright green light under ultraviolet irradiation.