Piezoelectrics
Piezoelectric materials produce an electrical current in response to mechanical stress, making them exceptional vibration sensors and actuators. Piezoelectric materials tend to be oxides, the most common example being quartz (SiO2). Stenner et al. show that the nanoporous gold impregnated with electrolyte solution produces an exceptionally large electrical charge in response to stress. The electrical response to strain comes from the charge polarization of internal interfaces. The distinct mechanism for generating a charge from traditional piezoelectrics suggests that other nanoporous metals may also be useful for electromechanical coupling applications.
Adv. Funct. Mater. 10.1002/adfm.201600938 (2016).