Ultraviolet excitation of photoluminescence of porous silica under vacuum conditions

Structure and Properties of Amorphous Silica and Its Related Materials: Recent Developments and Future Directions

“…The PL emission is quite stable after prolonged exposure to the atmosphere. (3) The observed PL decaytime constants (`100 ms) is rather long as compared with that reported previously for porous silica 102) (`10 ns) and unsintered silica nanoparticles observed by Glinka et al…”

“…It should also be worth mentioning that none of these PL activity matches known emissions of bulk silica, implying that the observed PL emissions result from microstructural characteristics of the porous materials. Anedda et al 102) sug gested that the surface OH groups are related to the UV PL emission from porous silica, but currently no accepted assign ments for the PL centers have yet been given.…”

Mesoporous silica photoluminescence properties in samples with different pore size

“…In particular, a correlation of surface hydroxyl species with the emission at 335 nm has been recently proposed [12,21]. Moreover the dependence of the emissions on the surface equilibrium condition was proven [13].…”

“…The reported spectra were recorded applying a short wavelength cut-off filter (WG295) and corrected for the optical transfer function of the system. Photoluminescence excitation spectra obtained by collecting the PL emission at different excitation energies are corrected for the spectral variations of the excitation light intensity and for the sample absorption [13,14]. Porous silica samples produced by Geltech (US) via solgel route are provided in disks (diameter 6 mm, thickness 2 mm).…”

Visible and ultraviolet emission of porous silica excited by synchrotron radiation

“…By exciting at 5.6 eV, well inside its main absorption band [11], PS displays visible and ultraviolet (UV) PL attributed to surface centers: the chemical and physical structure of the PS surface affects the efficiency and emission range of the PL [4,[12][13][14][15][16][17]. Among the contributions, the 3.7 eV component has been recently associated to OH-related surface defects [16,18].…”