Textured Potassium Sodium Niobate Lead-Free Ceramics with High d₃₃ and Q_m for Meeting High-Power Applications

Potassium sodium niobate (KNN) lead-free piezoceramics have garnered significant attention for their environmentally friendly attributes, desired piezoelectric activity (d(33)), and high Curie temperature (T-c). However, the limited applicability of most KNN systems in high-power apparatus, including ultrasonic motors, transformers, and resonators, persists due to the inherent low mechanical quality factor (Q(m)). Herein, we proposed an innovative strategy for achieving high Q(m) accompanied by desirable d(33) via synergistic chemical doping and texturing in KNN piezoceramics. Comprehensive electrical measurements along with quantitative structural characterization at multilength scales reveal that the excellent electromechanical properties (k(p) = 0.58, d(33) similar to 134 pCN-1, Q(m) = 582, and T-c similar to 415 degrees C) originate from the high <001> texturing degree, nanodomain, as well as acceptor hardening. Our findings provide an insight and guidance for achieving high-power performance in lead-free KNN-based piezoceramics, which were expected to be used in advanced transducer technology.