Composition induced rhombohedral–tetragonal phase boundary in BaZrO3 modified (K0.445Na0.50Li0.055)NbO3 lead-free ceramics

Composition and temperature dependence of structure and piezoelectricity in (1−x)(K1−yNay)NbO3‐x(Bi1/2Na1/2)ZrO3 lead‐free ceramics

“…(2004) reported giant d 33 ∼ 416 pC/N, comparable to those of PZTs, in textured (Li,Ta,Sb)‐modified KNN, However, disadvantages such as attaining well‐densified ceramics due to the high volatility of the alkaline components and low piezoelectric properties in polycrystalline ceramics have prevented KNN being commercialized . In general, dopants in KNN enhance piezoelectricity ( d 33 > 200 pC/N) by pushing the orthorhombic (O) to tetragonal (T) transition boundaries closer to room temperature . This effect is well documented for dopants such as LiSbO 3 , LiTaO 3 , Bi 0.5 Na 0.5 TiO 3 , and BaTiO 3 .…”

“…Recently, PZT‐like morphotropic phase boundary (MPBs) (R‐T) have been reported in KNN‐based ceramics by integrating compositions which were previously used to optimize the O‐T and R‐O phase boundaries . In 2011, Zuo et al.…”

“…obtained d 33 ∼ 425 pC/N . But more recently, Sb together with (Bi,M)NO 3 (M=Na, K, Li, Ag, N=Zr, Hf, Sn) have been used to enhance d 33 and electromechanical strain ( S ) with d 33 and S improved to >400 pC/N and 0.46% at 3 kV/cm, respectively . Despite promising d 33 and S values there are still a number of concerns.…”

Phase structure and electrical properties of 0.965(K0.45Na0.55)0.95Ag0.05(Nb1−x Sb x )O3–0.035Bi0.5(Na0.5Li0.5)0.5ZrO3 lead-free ceramics

“…Lead zirconate titanate {Pb(Zr,Ti)O 3 , PZT)} ceramics have been widely applied in commercial devices because of their excellent dielectric and piezoelectric properties [1]. However, the lead-based ceramics like PZT have seriously damaged both the environment and human health in the processes of their production, usage, and waste treatment [2,3].…”

“…substitutions for A site of KNN-based ceramics can shift orthorhombic-tetragonal phase transition temperature (T O-T ) downward near room temperature, in which Li ? has been proved to be the most effective alternative [1,7]. In addition, Sb 5?…”