Characterization of nickel doped CCTO: CaCu_(2.9)Ni_(0.1)Ti_4O_(12) and CaCu_3Ti_(3.9)Ni_(0.1)O_(12) http://CaCu3Ti3.9Nio.1O12 synthesized by semi-wet route

摘要

Nickel doped CaCu_3Ti_4O_(12) (CCTO) samples, i.e. CaCu_(2.9)Ni_(0.1)Ti_4O_(12) (CCNTO) and CaCu_3Ti_(3.9)Ni_(0.1)O_(12) (CCTNO) were prepared by semi-wet route using TiO_2 powder and metal nitrate solutions. According to both the stoichiometry, structure does not change on doping with nickel in both the samples and it remains cubic. Scanning electron micrographs (SEM) show that the grain size for both doped samples is in the range of 10-50 μm. Energy dispersive X-ray spectrometer (EDX) studies confirmed the presence of copper rich phase at grain boundaries. X-ray photoelectron spectroscopy (XPS) studies confirm the presence of Cu~(2+) and Ti~(4+) in both the samples of nickel doped CCTO ceramics. Dielectric constant (ε_r) and dielectric loss (tan δ) of Ni doped sample in CCTO on copper site is comparatively more than the Ni doped on titanium site sample.