Synthesis, characterization, EPR and thermoluminescence properties of CaTiO3 nanophosphor

Calcium titanate (CaTiO3) nanophosphors were synthesized by three different routes namely solution combustion (SC), modified solid-state reaction (MSS) and solid-state (SS) methods. Rietveld refinement studies revealed the presence of an orthorhombic structure with traces of CaCO3. The crystallite sizes were found to be in the 43–45 nm range. TEM studies also confirm the nano size with well crystalline nature. EPR spectrum for SS method exhibits a broad resonance signal at g = 2.027 is attributed to [TiO6]9− center, whereas in MSS sample the resonance signals are attributed to surface electron and hole trapping sites. The TL behavior has been investigated for the first time using γ-irradiation. TL glow peak at 169 °C were recorded in CaTiO3 prepared by SC, MSS and SS methods. The trapping parameters such as activation energy (E) and order of kinetics (b) were estimated using peak shape method and results are discussed in detail.

Packing diagram of CaTiO3 prepared by MSS method.Figure optionsDownload as PowerPoint slideHighlights
► Orthorhombic CaTiO3 nanophosphor was synthesized by three different routes.
► Well characterized by PXRD, SEM, TEM, FTIR, UV–vis spectroscopy.
► EPR spectrum reveals that g = 2.027 signal and is attributed to [TiO6]9− center.
► Subjected to γ-irradiation and TL behavior has been studied for the first time.
► Trapping parameters have been evaluated and discussed in detail.