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Lead-based ferroelectric materials dominate the electronic industry due to their possible applications in sensors, actuators, advanced storage materials, microwave devices, and MEMS. Due to the toxicity of lead, there is a need for the development of environmentally compatible alternatives. Lead-free ternary solid solutions of (1−2x)K0.5Bi0.5TiO3-xBaTiO3-xLiNbO3 (KBLN100x) with x = 0.03, 0.05, 0.07, and 0.09 are synthesized using a standard solid-state reaction method. X-ray diffraction studies confirm the pseudocubic structure of the samples. Structural, Raman, dielectric and piezoelctric studies indicate that a normal to relaxor ferroelectric transition occurs as dopant concentration increases, and it is attributed to the increase in charge fluctuation and site disorder that resulted in the reduction in correlation lengths of the inbuilt dipole moments. A recoverable energy density of 1.3 J/cm3 was achieved for the KBLN7 sample, making it an attractive candidate in the energy storage realm. A strain value of 0.17% with Smax/Emax of 218 pm/V is observed for KBLN3 sample, indicating that K0.5Bi0.5TiO3 (KBT)-based systems can be used for actuator applications on further improvement. The normal-relaxor crossover of KBT with appropriate dopants indicates that KBT-based systems are efficient for both actuator and energy storage applications on improvising and tuning as required.

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Here, we report the dynamic scaling of a ferroelectric material at the transition compositions, from normal ferroelectric to relaxor ferroelectric (relaxor), with K0.5B0.5TiO3 (KBT) as base material and LiNbO3 (LN) as the substituent. Ferroelectric (Polarization Vs Electric field), piezoelectric (Strain Vs. Electric field) and temperature dependent dielectric data reveals that 0.98KBT-0.02LN (KLN2) has more of normal ferroelectric character while relaxor character is dominating in 0.97KBT-0.03LN (KLN3). The dynamic scaling study with constant frequency and varying electric field shows the evolution of a four-stage behavior for KLN2, distinct from previous reports with two-stage and three-stage behavior, while KLN3 shows 3-stage dynamic behavior. The evolution of a four-stage dynamic behavior is attributed to the clamping of domain walls at lower electric fields. The dissolution of the first and second stages into a single stage with the increase of LN content from 2% to 3% is attributed to the extinction of the clamping effect due to the emergence of polar nanodomains. To generalize the dissolution of stages with the increase of relaxor character, further studies are required.