Formation and distinctive decay times of surface-and lattice-bound Mn~(2+) impurity luminescence in ZnS nanoparticles

摘要

The Mn~(2+) impurity luminescencedecay of Mn~(2+) -doped ZnS nanoparticles has been clearly distinguished from ZnS host emission decay by measuring transient absorption and emission kinetic profiles in the picosecond-millisecond time domain.The Mn~(2+) luminescence for the doped sampleshows two decay components of 0.18 and 2 ms.The fast one is attributed to surface-bound Mn~(2+) impurities and the slow one to lattice-bound Mn~(2+) impurities.In comparison,the slowest component of ZnS host emission decays within 20 ns.Moreover,excitation-energy transfer from ZnS host to Mn~(2+) impurity is also measured tooccur on the time scale of 700 ps.