Effects of humidity on the electrical behaviour of Sr_(0.97)Ti_(0.97)Fe_(0.03)O_(3- delta )

摘要

It is widely recognised that the electrical behaviour of acceptor-doped strontium titanate ceramics is often controlled by resistive grain boundaries. This work shows that the electrical behaviour of Sr_(0.97)Ti_(1-x)-Fe_xO_(3- delta ) materials may also be affected by other factors such as the humidity in the atmosphere, especially for materials with open porosity. For example, the impedance of dense samples with large grain size may exceed the impedance of samples with residual porosity. The bulk and grain boundary resistivities both increase with the humidity in the atmosphere.