Nitrogen-doped and gold-loaded TiO2 photocatalysts synthesized by sequential reactive pulsed laser deposition

Nitrogen-doped titanium oxide thin films covered by gold metal nanoparticles were grown on (001) SiO2 quartz substrates by pulsed laser deposition. A KrF* excimer laser source (λ = 248 nm, τFWHM ≤ 25 ns, ν = 10 Hz) was used for the irradiation of TiO2 and gold metal targets. The experiments were performed in controlled reactive oxygen or nitrogen atmosphere. The layers were grown for photocatalytic applications. Evaluation of photocatalytic activity was performed by photodegradation of methyl orange under near-UV light irradiation. Our results show that nitrogen doping and addition of gold nanoparticles have complementary effects, photoactivity being significantly improved as compared to that of pure titanium oxide.