Phase structure regulation and enhanced Curie temperature of (K,Na)NbO₃-based piezoelectric ceramics

High piezoelectric and dielectric constant of Fe/In Co‐doped KNN‐based ceramics regulated by lattice distortion

“…The ε r of the undoped ceramic is 2606, while it increases to 3432 when x = 0.003, as detailed in Figure 4(B). This work obtained high piezoelectric coefficient ( d 33 = 536 pC/N) and dielectric constant ( ε r = 3432) simultaneously in KNN‐based ceramics, as shown in Figure 5 19,28,41–54 . Conductivity and domain wall motion are the main factors controlling tan δ 55 .…”

“…The S pos reflects the sum of the intrinsic piezoelectric response strain and extrinsic reversible domain switching strain. The increase in S neg caused by the increase in grain size means the increase of non‐180 ° degree domains 53 . Increasing the grain size reduces the internal stress and facilitates domain switching, thus facilitating the retention of more non‐180 ° domains after polarization.…”

“…This work obtained high piezoelectric coefficient (d 33 = 536 pC/N) and dielectric constant (ε r = 3432) simultaneously in KNN-based ceramics, as shown in Figure 5. 19,28,[41][42][43][44][45][46][47][48][49][50][51][52][53][54] Conductivity and domain wall motion are the main factors controlling tan δ 55 . The tan δ is further reduced by a small amount of Fe 3+ and In 3+ , indicating that the conductivity of the ceramics is also low, as seen in Figure S1 and Table S1.…”

“…The increase in S neg caused by the increase in grain size means the increase of non-180 • degree domains. 53 Increasing the grain size reduces the internal stress and facilitates domain switching, thus facilitating the retention of more non-180 • domains after polarization. S pos and S neg increased with…”