Question

what are piezoelectric materials

Answer 1

Piezoelectricity is the electric charge that accumulates in certain solid materials in response to applied mechanical stress

Answer 2

Piezoelectric materials are materials that produce an electric current when they are placed under mechanical stress. The piezoelectric process is also reversible, so if you apply an electric current to these materials, they will actually change shape slightly (a maximum of 4%).

There are several materials that we have known for some time that posses piezoelectric properties, including bone, proteins, crystals (e.g. Quartz) and ceramics (e.g. Lead Zirconate Titanate).

However, in May 2012, it was announced that University of California Berkeley lab scientists have found a mechanism of harnessing piezoelectricity from viruses. This is the first time a biological material has been used to make piezoelectricity.

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