Diamond's Century-Old Reputation Shattered: Polycrystalline Membranes Show Strong Piezoelectricity
Piezoelectric effect in polycrystalline diamond membranes
For over a century, diamond was considered non-piezoelectric. Now, ultrathin polycrystalline diamond membranes exhibit a notable piezoelectric effect, with a peak response at ~5 micrometers thickness. The piezoelectric voltage coefficient reaches ~82.2 mV·m/N, surpassing many conventional materials. First-principles calculations attribute the effect to local asymmetry at grain boundaries. These flexible, robust membranes could enable energy harvesting, sensing, and wearable electronics.
Diamonds have been regarded as nonpiezoelectric materials for more than one century. Here, we uncover a notable piezoelectric effect in ultrathin and ultraflexible polycrystalline diamond membranes.