Structural XANES characterization of Ca0.99Sm0.01TiO3 perovskite and correlation with photoluminescence emission

In this work, CaTiO₃:Sm (CT:Sm) were prepared by a soft chemical processing at different annealing temperatures starting with a disordered structure and reaching an ordered one, with the propose to understand the relationship between structural order-disorder and photoluminescence emission. The samples were characterized by titanium K-edge, Titanium L_II and L_III-edge XANES, electron paramagnetic resonance (EPR) and photoluminescence (PL) measurements. XANES results clearly point the presence of local distortion in [TiO₆] octahedral clusters until the crystallization was completed. The interactions of the network clusters that form the CT:Sm structures provides favorable structural and electronic conditions for the appearance of PL phenomena.