Theoretical Prediction and Experimental Validation of Enhancing the Piezoelectric Properties of (K, Na)NbO 3 Modified by Li, Ta, and Sb According to the Linear Combination Rule

Lead‐free piezoelectric ceramics of ( K , Na ) NbO 3 modified by Li , Ta , and Sb (KNN‐LTS) have been widely investigated recently. In this research, this optimized composition of KNN‐LTS ceramics near polymorphic phase transition is explored according to the linear combination rule (LCR) for the first time. Changing with the compositions monotonically, remanent polarization ( P r ) decreased monotonically, whereas permittivity ( ) increased similarly. The increase in either or P r initially enhances piezoelectric coefficient d 33 before reducing it because d 33 can be improved by and P r . The optimal composition of ( Na 0.52 K 0.4415 Li 0.0385 )( Nb 0.8735 Ta 0.064 Sb 0.0625 ) O 3 , predicted by LCR, exhibits the excellent electric properties of d 33 = 359 pC/N, k p = 42%, thus suggesting that the LCR effectively predicts the electric properties of the KNN‐LTS ceramics.