1：Experimental Design and Method Selection:

The ceramics were synthesized using conventional solid-state reaction method. The overall design rationale was to create a new ternary system (BNT-KT-ST) to improve strain properties under low electric fields. Theoretical models involved phase transition behavior between nonergodic relaxor and ergodic relaxor states.

2：Sample Selection and Data Sources:

Compositions of (0.99-x)Bi1/2Na1/2TiO3-0.01KTaO3-xSrTiO3 with x = 0.20, 0.21, 0.215, 0.225, 0.235 were prepared. Raw materials included Bi2O3, Na2CO3, TiO2, SrCO3, K2CO3, Ta2O5. Selection criteria were based on stoichiometric formulas after drying at 100°C for 24 h.

3：99-x)Bi1/2Na1/2TiO3-01KTaO3-xSrTiO3 with x = 20, 21, 215, 225, 235 were prepared. Raw materials included Bi2O3, Na2CO3, TiO2, SrCO3, K2CO3, Ta2OSelection criteria were based on stoichiometric formulas after drying at 100°C for 24 h. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Raw materials: Bi2O3 (

4：99%), Na2CO3 (0%), TiO2 (99%), SrCO3 (9%), K2CO3 (0%), Ta2O5 (9%). Equipment:

Polyethylene jar with ZrO2 balls (5-10 mm diameter), ethanol as solvent, ball milling at 400 rpm for 24 h, calcination furnace (850°C for 2 h, heating rate 5°C/min), sintering furnace (1175°C for 2 h), polyvinyl alcohol (PVA) binder, electronic densimeter (SD-120L, A&D, Japan), X-ray diffractometer (XRD RAD III, Rigaku, Japan), field-emission electron microscope (FE-SEM, JEOL, JSM-65OFF, Japan), high temperature electric prober system (KEYSIGHT-E4980AL Precision LCR Meter, USA), commercial aixPES setup (aixACCT aixPES, Aachen, Germany).

5：Experimental Procedures and Operational Workflow:

Weighing and drying raw materials → mixing and milling with ZrO2 balls and ethanol for 24 h → drying at 100°C for 24 h → calcination at 850°C for 2 h → ball milling again → adding PVA binder → forming disk-shaped green bodies (12 mm diameter, 1.2 mm thickness) → sintering at 1175°C for 2 h → density measurement by Archimedes' principle → XRD characterization (20-70 degrees, step size 0.02°, speed 2°/min) → SEM microstructure study → electrode formation with silver paste sintered at 700°C for 30 min → dielectric property measurement with LCR meter → polarization and strain measurement with aixPES at 1 Hz.

6：2 mm thickness) → sintering at 1175°C for 2 h → density measurement by Archimedes' principle → XRD characterization (20-70 degrees, step size 02°, speed 2°/min) → SEM microstructure study → electrode formation with silver paste sintered at 700°C for 30 min → dielectric property measurement with LCR meter → polarization and strain measurement with aixPES at 1 Hz. Data Analysis Methods:

5. Data Analysis Methods: XRD patterns deconvoluted and fitted using Voigt profile function; dielectric constant and loss analyzed for temperature and frequency dependence; polarization and strain curves analyzed for hysteresis and strain values; statistical comparison of properties across compositions.