Effect of the substitution of titanium by chrome on the structural, dielectric and optical properties in Ca0.67La0.22Ti(1−x)CrxO3 perovskites

Polycrystalline samples of Ca0.67La0.22Ti(1−x)CrxO3(x = 0 and x = 0.1) (CLT(1−x)Crx) were synthesized by high-temperature solid-state reaction technique. The effect of replacing of titanium by chrome in the B site on the structural and physical properties of our compound was investigated. Using X-ray diffraction, scanning electron microscopy as well as dielectric characterizations and photoluminescence spectroscopy. These compounds crystallize with orthorhombic symmetry. The material is a classical ferroelectric for x = 0 and presents a relaxor behavior for x = 0.1. TC or Tm decreases when chrome is introduced in the lattice of CLT. A high permittivity of around 25,000 at Tm = 551 K for CLT0.9Cr0.1 was found, which opens the way for its possible use for capacitor applications. The observed increase in dielectric loss is explained in terms of changing oxygen vacancy concentration. The photoluminescence (PL) spectra confirm the dielectric measurements and suggested the formation of oxygen vacancies in the CLT(1−x)Crx sample.