Piezoelectric Sensors

Lateral‐Structure Single‐Crystal Hybrid Perovskite Solar Cells via Piezoelectric Poling

“…This device showed positive and negative voltage pulse when it was squeezed and released by simple striking it gently (Figure 1 b), providing a direct evidence for the presence of piezoelectric effect in MAPbI 3 single crystals. [ 31,32 ] We did not see such a phenomenon in the reference device based on MAPbI 3 polycrystalline thin fi lm with the same test condition as single crystal devices. This possibly due to the random distribution of grain orientation in polycrystalline fi lms, which indicates a single crystal is critical for the piezoelectric property measurement.…”

“…The grain boundaries caused by the crystal facture, which is caused by the piezoelectric poling, in single crystal enabled ion migration, which resulted in the p -i -n structure formation. Piezoelectric effect is a reversible process exhibiting both the direct piezoelectric effect (electrical charges generated by an applied mechanical force) and reverse piezoelectric effect (mechanical strain response to an applied electrical fi eld) [ 31,32 ] Previous work of Coll et al has studied the local piezoelectric response of polycrystalline OTP fi lm with piezoresponse force microscopy (PFM) measurement. [ 33 ] Nevertheless, study of the piezoelectric response from a large size single-crystal device is needed for direct evidence and quantitative measurement of the piezoelectric properties of OTP crystals, since the local PFM study on polycrystalline fi lm could be limited by the inaccurate estimation of tip contact area and other artifacts [ 34 ] coming from surface topography and crystal orientation.…”

Magnetic Amorphous Micro-Force Sensor

“…They have broad measurement range, are mechanically robust, and have high sensitivity. However, they are suitable only for dynamic load measurements, with the best available transducers allowing for quasi-static forces detection [2,3]. The most demanding force sensing applications are encountered in mass measurement, especially in analytic scales.…”

Progress in Piezo‐Phototronic‐Effect‐Enhanced Light‐Emitting Diodes and Pressure Imaging

“…Traditional piezoelectric materials such as Pb(Zr x Ti 1− x )O 3 (PZT) and poly(vinylidene fluoride) (PVDF) are almost dielectric and excluded as building blocks for functional electronics . The effect of mechanical strain‐induced polarization on electronic transport processes of charge carriers in piezoelectric materials has therefore been long overlooked …”