Author/Authors :
Lee، نويسنده , , Y.C. and Liu، نويسنده , , Y.L. and Shen، نويسنده , , Ji-Lin and Hsu، نويسنده , , I.J. and Cheng، نويسنده , , P.W. and Cheng، نويسنده , , C.F. and Ko، نويسنده , , C.-H.، نويسنده ,
Abstract :
Various photoluminescence (PL) methods were used to investigate the blue–green luminescence from mesoporous MCM-48 molecular sieves. The blue–green luminescence intensity is enhanced after rapid thermal annealing. The surface properties of the mesoporous MCM-48 molecular sieves reveal that the generation of twofold coordinated Si centers and non-bridging oxygen hole centers is responsible for this enhancement. Studies of PL following rapid thermal annealing, polarized PL and PL excitation strongly suggest that a triplet-to-singlet transition of twofold-coordinated silicon centers is responsible for the blue–green luminescence in mesoporous MCM-48 molecular sieves.
