Investigation of Zn2TiO4 as fluorescence quenching probe for sensing of metal ions

Abstract

In the present work, rutile-free Zn2TiO4 has been synthesized by the solid-state method using TiO2 as hydrated titania and ZnO of 1:2 molar ratio. The reaction mixture was calcined at different temperature ranges, 550 °C to 950 °C. The rutile-free, cubic spinel-type Zn2TiO4 powders were obtained at 950 °C and confirmed by Raman, FI-IR spectroscopy, and XRD results. SEM images showed that the particles are irregular micron-sized and highly aggregated. From the diffuse reflectance spectral studies, the optical bandgap of the calcined products was calculated and it was found to be in the range of 3.25 to 3.79 eV. An attempt was made to examine the metal ion sensing properties of the prepared Zn2TiO4, by monitoring their photoluminescence intensity via quenching effects upon adding various metal ions. The sensing abilities were also evaluated using the standard Stern–Volmer quenching model. The results showed that Zn2TiO4 possesses high sensitivity toward iron ions.

Keywords

• Zn2TiO4
• Raman spectroscopy
• Scanning electron microscopy
• FT-IR
• Bandgap
• Sensitivity of metal ions