High temperature induced pyroelectricity in screen-printed Hydroxyapatite thick films

This papers reports on the electrical properties of Hydroxyapatite (HA) in the form of screen-printed thick films with novel paste composition In particular, it is revealed for the first time that both high temperature treatment alone and a combination of high temperature and high voltage, i.e. poling, can cause comparable surface modifications resulting in pyroelectric behavior being recorded off HA thick film surface. Moreover, a reversible pressure-induced changes in the values of capacitance recorded in real time confirmed the piezoelectric behavior of HA thick films. Hydroxyapatite is biocompatible material, whose electrical characteristics can be employed in implantable devices for real-time in vivo pressure sensors applications such as in knee or hip prosthesis. In particular, piezo- and pyroelectric behaviour of these films suggest that they can have potential biosensor applications. The investigation of the electric properties of HA thick films is vital for the understanding of their bioactive characteristics for effective application in medical industry.