Ultraviolet luminescence of polycyclic aromatic hydrocarbons in partially consolidated sol-gel silica glasses

•Structured ultraviolet luminescence bands in silica glass are related to carbon.•Bands in 3.7 eV–3.8 eV region are due to interstitial naphthalene molecules.•Bands in 3.1 eV–3.3 eV region are due to interstitial pyrene molecules.•Polycyclic hydrocarbons in silica glass matrix are thermally stable up to 1000 °C.•They may serve as a source of carbon ring structures in C-doped silica.