Tuning the Ferroelectric and Piezoelectric Properties of 0.91Pb(Zn1/3Nb2/3M/sub>)O-3-0.09PbTiO3 Single Crystals and Lead Zirconate Titanate Ceramics by Doping Hydrogen

Systematically experimental investigations were conducted on H-doped 0.91Pb(Zn1/3Nb2/3)O-3-0.09PbTiO(3) (PZNT) single crystals and lead zirconate titanate (PZT) ceramics. The experimental results show that doping hydrogen with appropriate content advances the ferroelectric and piezoelectric properties effectively. For example, when trapped hydrogen concentration was C-1 = 1.7 wppm in the H-doped PZNT single crystals, the remanent polarization P-r and piezoelectric constant d(33) increased by 80\% and 41.7\% in comparison with the H-free samples, respectively, to 28.8 mu C/cm(2) and 391 pC/N. However, high hydrogen concentration damages the ferroelectric and piezoelectric properties. The remanent polarization P-r and piezoelectric constant d(33) of the H-doped PZNT single crystals decreased to 0 mu C/cm(2) and 24 pC/N, respectively, when C-1 = 3.1 wppm. The H-doped PZT ceramics exhibited the same behavior, where the values of P-r and d(33) increased respectively by 45.3\% and 27.3\% to 48.1 mu C/cm(2) and 420 pC/N, when C-t = 1.1 wppm, and decreased to 0 mu C/cm(2) and 84 pC/N, respectively, as C-t increased to 2.1 wppm. Hydrogen also increases the dielectric constant and dielectric loss for both ferroelectric materials. The experimental results indicate that doping hydrogen into ferroelectric materials is a feasible technique to tune the ferroelectric and piezoelectric properties effectively, furthermore as a subsequent treated technology for the ferroelectric product.