The effect of Ni doping on the properties of BaTiO3 based X7R ceramic materials

The effect of Ni doping on the dielectric properties of BaTiO3 based X7R ceramic materials were investigated. Ni powder with the grain size of 50 nm is mixed with X7R materials by different volume content, milled in alcohol for 24 h and sintered in reducing atmosphere. The results show that with increasing of Ni content, the dielectric constant of the ceramic at room temperature also increases. When the content of Ni is 28vol%, the dielectric constant is 7 166, which is 2.9 times of that without Ni doping. On the other hand, with increasing of Ni content, the temperature stability decreases rapidly. When Ni content is larger than 30%, the samples become semiconductor, which are not suitable for MLCC. X-ray diffraction shows that no chemical reaction occurs between BaTiO3 and Ni.