An efficient luminescent DBR-PS-based sensor for chemical warfare agent vapor detection

A highly sensitive detection method utilizing luminescent distributed Bragg reflector porous silicon (DBR PS) is developed for the rapid detection of dimethyl methylphosphonate (DMMP), tetraethyl phosphate (TEP), and diethyl ethylphosponate (DEEP), simulants for chemical nerve agents. The engineered DBR PS chip demonstrates sharp photoluminescence and reflectance peaks at 680 nm. The sensing mechanism is based on the quenching of the photoluminescence (PL) signal upon exposure to DMMP, TEP, and DEEP vapors. This quenching occurs within seconds and can be observed in situ. It results from the oxidation of silicon nanocrystallites in the porous silicon structure, leading to the formation of a silicon oxide layer on the DBR PS surface.