INFLUENCE OF PREPARATION PROCEDURE ON SOME PHYSICAL-PROPERTIES OF BICUVOX

The influence of preparation conditions on some physical properties of BICUVOX.10 (Bi2V0.90Cu0.10O5.35) is reported. Differential thermal an d X-ray analyses indicate that synthesis of the compound can be accomp lished at 610-degrees-C. The densification characteristics show that h igh density BICUJVOX ceramic can be obtained after several minutes of sintering at 800-degrees-C. The electrical conductivity was studied by a.c. impedance methods. Separation of the contributions of grain inte riors and grain boundaries to the total resistance was possible at tem peratures below around 350-degrees-C. The Arrhenius plots of the total conductivity consist of two straight line sections with a change in s lope at around 500-degrees-C. The activation energy was about 0.48 eV at high temperatures for all the samples. Below around 500-degrees-C t he activation energy was in the range from 0.62 to 0.72 eV depending o n the preparation procedure. Lower values of activation energy and hig her values of conductivity were obtained for well-sintered samples, wh ich is related to the smaller contribution of the grain boundaries to the total electrical resistance of a sample.