Enhancing strain performance in KNN-based ceramics profiting from synergistic effect at ferroelectric-to-relaxor cross region

Owing to the demand for sustainable development, a lot of attention has been received by eco-friendly lead-free KNN based ceramics. Although a series of breakthroughs have been achieved in their electric properties, their poor temperature stability still hinders their practical application. A KNN-based ceramic of (1-x) K0.54Na0.46NbO3-xBi(0.5)Na(0.5)ZrO(3) (KNN-xBNZ) was designed to solve the issue of temperature-dependent degradation while taking advantage of the synergistic effect at the ferroelectric-to-relaxor cross region. A mixed-phase boundary, including tetragonal and pseudocubic phases, is observed in all samples, and the dominant phase structure gradually transforms from a tetragonal phase to a pseudocubic phase as BNZ increases. A favorable strain performance (strain >= 0.08%, and temperature stability >= 95.35%) is observed at the temperature range of 20-180 degrees C, profiting from the synergistic effect at the ferroelectric-to-relaxor cross region at x = 0.08. It is superior or comparable to some typical NN-based, KNN-based, and PZT-based materials regardless of the driving electric field. These results would shed light on the future work of achieving excellent comprehensive performance in KNN-based materials.