Nanoparticles of the giant dielectric material, calcium copper titanate from a sol–gel technique

The precursor of CaCu3Ti4O12 (CCTO) nano particles have been successfully synthesized by sol–gel method at 90 °C. The dried precursor powder was milled and then calcined at 450 °C, 550 °C, 650 °C, 800 °C, 850 °C and 950 °C for 3 h. The phase formation of CCTO was analyzed by step by step using FTIR and XRD. Particle size and shape were evaluated by AFM. The XRD results of the powder calcined at 800 °C indicated the formation of CCTO phase. AFM studies showed that average particle size of the CCTO powder range 90–120 nm. The absorption bands corresponding to vibrations of CaO, CuO and TiOTi were observed at 606, 525 and 463 cm− 1 using FTIR. The samples sintered at 1040 °C showed the densities as high as 96% of theoretical density. The grain sizes of sintered pellets were determined by FE-SEM. The dielectric properties of prepared samples were studied by LCR meter.

► CCTO powder has been synthesized using sol gel process.
► The particle size of the powder ranges from 90–120 nm.
► Less sintering at 1040 °C results in density as high as 96%.
► High dielectric constant of 50,300 has been obtained at 50 Hz.
► The dielectric constant drops to 11,000 at 1.0 MHz.