Relaxor ferroelectric

"Relaxor" redirects here. For the hair treatment, see Relaxer.

Relaxor ferroelectrics are ferroelectric materials that exhibit high electrostriction. As of 2015^[update], although they have been studied for over fifty years,^[1] the mechanism for this effect is still not completely understood, and is the subject of continuing research.^[2][3][4][5]

Examples of relaxor ferroelectrics include:

• lead magnesium niobate (PMN) ^[6][7][8]
• lead magnesium niobate-lead titanate (PMN-PT) ^[9]
• lead lanthanum zirconate titanate (PLZT)^[10]
• lead scandium niobate (PSN) ^[11]
• Barium Titanium-Bismuth Zinc Niobium Tantalum (BT-BZNT)^[12]
• Barium Titanium-Barium Strontium Titanium (BT-BST) ^[13]

Applications

Relaxor Ferroelectric materials find application in high efficiency energy storage and conversion as they have high dielectric constants, orders-of-magnitude higher than those of conventional ferroelectric materials. Like conventional ferroelectrics, Relaxor Ferroelectrics show permanent dipole moment in domains. However, these domains are on the nano-length scale, unlike conventional ferroelectrics domains that are generally on the micro-length scale, and take less energy to align. Consequently, Relaxor Ferroelectrics have very high specific capacitance and have thus generated interest in the fields of energy storage.^[10] Furthermore, due to their slim hysteresis curve with high saturated polarization and low remnant polarization, Relaxor ferroelectrics have high discharge energy density and high discharge rates. BT-BZNT Multilayer Energy Storage Ceramic Capacitors (MLESCC) were experimentally determined to have very high efficiency(>80%) and stable thermal properties over a wide temperature range.^[12]