Reverse photodegradation of infrared luminescence of colloidal Ag2S quantum dots

Abstract Regularities of reverse photodegradation of infrared (IR) luminescence of colloidal Ag 2 S quantum dots (QDs), stabilized in gelatin with the average size of 1.6 nm ( λ lum max = 1205 nm) and passivated with thyoglicolic acid with the average size of 2.3 nm ( λ lum max = 1095 nm) were discussed. The photochemical nature of this process was found. The evidences of the formation of nonradiative recombination centers near the IR luminescence centers was found. These centers disintegrate in the dark with the activation energy of 0.9 eV and ensure the recovery of intensity IR luminescence of Ag 2 S QDs by 65–75%.