Properties of non-stoichiometric 0.935(K0.5+xNa0.5+x)NbO3-0.065LiSbO3 lead-free piezoelectric ceramics

► The volatilization loss of alkaline elements were effectively compensated by adding excess Na/K. ► Good piezoelectric properties were obtained. ► The results could guide the design of high performance KNN-based piezoceramics.