Enhancement of visible light irradiation photocatalytic activity of ${\text{SrTiO}}_3$ nanoparticles by Pt doping for oxidation of cyclohexane

In this research, strontium titanate (${\text{SrTiO}}_3)$ nanoparticles were synthesised using an ultrasonic method, then were doped with Pt using a photo-assisted deposition method to form $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles. ${\text{SrTiO}}_3$ and $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles were characterized by XRD, XPS, TEM, BET surface area UV–Vis and PL techniques in order to explore their chemical and physical properties. The visible light irradiation photocatalytic performances of ${\text{SrTiO}}_3$ nanoparticles and $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles for photocatalytic oxidation of cyclohexane was investigated, and the results revealed that platinum was doped onto the ${\text{SrTiO}}_3$ nanoparticles surfaces as metallic platinum, and the weight percent of doped platinum greatly affected the band gap, and the 1.5 wt% $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles showed the highest photocatalytic activity due to the low band gap. The stability of the $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles for the photocatalytic oxidation of cyclohexane was examined and the results revealed that the $\text{Pt}/{\text{SrTiO}}_3$ nanoparticles could be used five times without losing their efficiency.

Graphical Abstract

TEM images of ${\text{SrTiO}}_3$ (A) and 1.5 wt% $\text{Pt}/{\text{SrTiO}}_3$ (B) nanoparticles, which showed that ${\text{SrTiO}}_3$ is a spherical nanoparticle (A) and that platinum was doped as dots (B). .