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RESEARCH PRODUCT
Luminescence of the surface nonbridging oxygen hole center in silica: Spectral and decay properties
Lavinia VaccaroRoberto BoscainoV. RadzigMarco Cannassubject
Surface (mathematics)Materials sciencebusiness.industryTime resolved luminescenceOptoelectronicsdefects nanoparticles luminescence time resolved measurements silicaCenter (algebra and category theory)Condensed Matter PhysicsbusinessLuminescencePorous mediumElectronic Optical and Magnetic MaterialsNonbridging oxygendescription
We investigated the red luminescence in a porous film of silica nanoparticles, originating from surface nonbridging oxygen hole centers. The excitation spectrum was measured from 1.8 to 8.0 eV by a tunable laser system and a synchrotron radiation source; this spectrum evidences a peak at 2.0 eV, nearly overlapping with the emission, and an ultraviolet broadband with peaks at 4.8 and 6.0 eV. The emission is characterized by a spectrum with two subbands split by 0.07 eV, its decay occurs with lifetime longer than 30 microsec and undergoes a thermal quenching by a factor aboout 2 with increasing temperature from 10 to 290 K. The optical characteristics of surface and bulk centers are discussed on the basis of the reported experimental results and quantum chemical calculations.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-08-18 |