Structural and Electrical Transport Properties of ZnO doped Calcium Titanate

A series of perovskite type compounds ZnxCa1-xTiO3(x=0.1 to 0.9) were synthesized by ceramic technique in air (final temperature 950°C). Crystal structure of the ZnxCa1-xTiO 3 compounds was characterized at room temperature as rhombohedral in space group R-3 (148) (samples with 0.4≥x≥0.1). It was also observed that Zn atoms replaced Ca atoms at B sites. Electrical conductivity was studied from room temperature upto 600K. The compounds were found to be p-type conducting and conductivity increases with the increase of temperature. Conductivities are in the range of 6X10 -9 to 5X10 -10 mho/cm. Maximum conductivity was observed for x=0.1. As Zn concentration increases electrical conductivity decreases for upto x=0.4 and then conductivity gradually increases indicating multiple phases of perovskites. Thermoelectric power measurements were also carried from room temperature upto 600K. Thermoelectric power varies from 1800 µV/K to 300µV/K as x varies from 0.1 to 0.9. Maximum thermoelectric power was observed for x=0.1. It was found that thermoelectric power decreases with the increase of temperature for all the samples. Structural properties were correlated with the electrical transport properties in these compounds.