largest usable strain shown in BNT-based solid solutions make them the most feasible lead-free materials for actuator applications. [1e,2] The major challenge for the technological application of BNT-based systems is the relatively low depolarization temperature (T d ), which is in the range from 80 to 100 °C for 0.94Bi 1/2 Na 1/2 TiO 3 -0.06BaTiO 3 (BNT-BT6). The thermal depolarization in BNT-based materials leads to a pronounced reduction of macroscopic electrical properties at T d , including the piezoelectric coefficient d 33 , the remanent polarization (P r ), and the negative strain (S neg ). [1d,3] As a consequence, the T d determines the maximum working temperature. Various approaches have been attempted to increase the T d . [4] Stress induced either by direct loading [4b] or by constructing composite structure [4a,d] is found to effectively increase the T d and broaden the temperature range in which the thermal depolarization takes place. It is believed that the stress, especially a uniaxial stress, can stabilize the ferroelectric long-range order and modulate the relaxor-toferroelectric (RE-FE) phase transition.In traditional ferroelectric thin films, the effect of stress on the phase transition temperature has been systematically studied. [5] Compared with bulk ceramics, it is much easier to introduce stress in thin films by modulating the properties of the sample and the substrate or the buffer layer, such as the thermal expansion coefficient and the lattice parameter. An efficient enhancement in Curie temperature (T c ) has been found by inducing the in-plane stress in several ferroelectric materials, such as PbTiO 3 and BaTiO 3 . [5,6] The enhancement of T c in ferroelectric perovskites has been explained by Devonshire thermodynamic formalism and interpreted as a stabilization of the long-range ferroelectric order. [6a,7] Through strain engineering, the in-plane stress could not only increase the T c but also enhance the ferroelectric properties of BaTiO 3 thin films. [8] It is worth mentioning that the stress-induced stabilization of the long-range ferroelectric order is only applicable to the case when the stress is perpendicular to or along the polarization vectors. Consequently, to enhance the phase transition temperature by modulating the in-plane stress, the film with specific orientations is preferred.Based on the analysis above, it is expected that the stabilization of long-range ferroelectric orders through Future microelectromechanical systems will need environmentally friendly lead-free piezoelectrics in the form of thin films, like Bi 1/2 Na 1/2 TiO 3 (BNT); however, its application is limited due to the relatively low depolarization temperature (T d ). In this work, not only enhanced piezoelectric properties, but also higher T d , are achieved in (001)-textured 0.94Bi 1/2 Na 1/2 TiO 3 -0.06BaTiO 3 (BNT-BT6) thin films on widely used platinized Si wafers with a LaNiO 3 buffer layer. The piezoelectric coefficient a 33,eff is increased by 65% to 43 pm V −1 in the textured films fr...