Piezoelectric materials–ie., those that generate an electrical voltage when pressure is applied to them–clearly have a lot of promise in terms of renewable energy, but applications so far have tended to hover in the conceptual realm. Recently, engineers at Princeton University have taken piezoelectrics a little closer to practical application with power-generating rubber films that could power the pacemakers of the future.
According to a release, the films are composed of ceramic nanoribbons of piezoelectric material embedded onto silicone rubber sheets. These nanoribbons are highly efficient at converting mechanical energy into electrical energy, and when placed against the lungs, sheets of these power-generating rubber films could use the pressure exerted by the motion of breathing to power pacemakers. (That would be a huge boon to those whose lives depend on the medical devices, as current technology requires surgery to replace batteries.)
The heart of the new material is lead zirconate titanate (PZT), considered to be the most efficient of all piezoelectric materials, able to convert 80 percent of the mechanical energy applied to it into electrical energy. A paper on the new material–“Piezoelectric Ribbons Printed Onto Rubber for Flexible Energy Conversion”–was recently published online in Nano Letters, a journal associated with the American Chemical Society.