Leading the Way to Lead-Free Piezoelectrics
LQ13398 -
Energy
and environment are two pressing global challenges. Piezoelectric
materials enable the conversion between
electrical and mechanical energies, and have been used in many important applications, such as devices
for ultrasound medical imaging and for energy harvesting from vibrations. In the past
six decades, lead-containing ceramics (greater than 60% weight of lead) have
dominated the piezoelectric technology even though they pose a serious threat to the environment and human health. For best piezoelectric performances, the
compositions are fine tuned to be at the so-called morphotropic phase boundaries
and the ceramics go through a poling processing where they are exposed to a
highest possible electric field. A recent discovery (to be published in the September 6 issue of Physical Review Letters) breaks the ice for new lead-free piezoelectrics. The original approach of
poling to the highest possible field is incorrect and the composition is not
necessary to be at the morphotropic
phase boundary. Such
a fundamental alteration to the long-standing paradigm adds a new dimension to the development of
high-performance lead-free piezoelectrics.
LQ13398 - Energy
and environment are two pressing global challenges. Piezoelectric
materials enable the conversion between
electrical and mechanical energies, and have been used in many important applications, such as devices
for ultrasound medical imaging and for energy harvesting from vibrations. In the past
six decades, lead-containing ceramics (greater than 60% weight of lead) have
dominated the piezoelectric technology even though they pose a serious threat to the environment and human health. For best piezoelectric performances, the
compositions are fine tuned to be at the so-called morphotropic phase boundaries
and the ceramics go through a poling processing where they are exposed to a
highest possible electric field. A recent discovery (to be published in the September 6 issue of Physical Review Letters) breaks the ice for new lead-free piezoelectrics. The original approach of
poling to the highest possible field is incorrect and the composition is not
necessary to be at the morphotropic
phase boundary. Such
a fundamental alteration to the long-standing paradigm adds a new dimension to the development of
high-performance lead-free piezoelectrics. 