Highly Sensitive Piezoelectric Response of Sodium Nitrite Nano-crystals to Low Applied Mechanical Pressures

Development of highly-sensitive detectors of low mechanical pressures in the scale of few Pascal and below in environmental conditions are of a high technological demand for a variety of applications such as a remote control of infants breathing and a leakage alert of hazardous gases.This paper reports on a highly sensitive piezoelectric detector of low applied mechanical pressures down to 0.1 Pa in atmospheric environment(10-4%pressure change).It is made of SN(sodium nitride)nanocrystals grown inside alumina pores with a preferred crystallographic orientation that can be controlled by their formation conditions based on a thermodynamic driving force.The SN nanocrystals inside the pores show a piezoelectric current response to low applied mechanical pressure which depends on the crystallographic orientation of the crystals and the level of residual or applied static strains.The piezoelectric current response is correlated with the unique molecular structure of the SN crystals.