Tuning the dielectric and optical properties of PrCo–substituted calcium copper titanate for electronics applications

Publication date: Available online 15 October 2018Source: Journal of Physics and Chemistry of SolidsAuthor(s): J. Mohammed, Tchouank Tekou T. Carol, H.Y. Hafeez, B.I. Adamu, Y.S. Wudil, Z.I. Takai, Sachin Kumar Godara, A.K. SrivastavaAbstractPrCo–substituted calcium copper titanate (CCTO) ceramic with chemical composition Ca1-xPrxCu3-yCoyTi4O12 (x = 0.0, 0.1, 0.2, 0.3 and y = 0.0, 0.4, 0.5, 0.6) was synthesized by the sol-gel method. The X-ray diffraction patterns indicate that all the synthesized samples exhibit a pure phase of CCTO ceramic with absence of secondary phases such as CaTiO3 and CuO. The weight losses observed in the thermogravimetric analysis graph cease to occur at 895 °C, indicating the formation of the final CCTO product. Field-emission scanning electron microscopy micrographs show dense and closely arranged faceted grains with the absence of agglomeration and liquid oxide phase. Energy-dispersive X-ray spectroscopy spectra confirm the stoichiometry of the synthesized CCTO ceramic, and Raman analysis rules out the presence of secondary phases; hence, the purity of the synthesized CCTO ceramic is further supported by Raman and energy-dispersive X-ray spectroscopy spectra. The optical band gap increased with PrCo substitution, and a maximum value of 3.88 eV was obtained in the sample with x = 0.0/y = 0.0. The dielectric properties are explained on the basis of a Maxwell-Wagner relaxation process. The sample with x = 0.0/y = 0.0 s...
Source: Journal of Physics and Chemistry of Solids - Category: Physics Source Type: research