1：Experimental Design and Method Selection:

The study used non-conventional synthesis methods (Sol-gel and Single-step solid state method) to prepare (1-x)BiFeO3-xPbTiO3 solid solutions with x=0.3, 0.4, 0.5, 0.6. The rationale was to reduce volatilization of Bi and Pb, minimize defect formation, and avoid impurity phases.

2：3, 4, 5, The rationale was to reduce volatilization of Bi and Pb, minimize defect formation, and avoid impurity phases. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Samples were prepared with specific compositions (N1-N4 for Sol-gel, S1-S4 for Single-step method) using high-purity precursors. Data were collected from XRD, SEM, dielectric measurements, and ferroelectric tests.

3：List of Experimental Equipment and Materials:

Equipment included PANalytical Empyrean Diffractometer for XRD, JSM-7610F Schottky Field Emission Scanning Electron Microscope for SEM, Wayne-Kerr model 4275 LCR meter for dielectric measurements, and Radiant Technologies Precision LC II Ferroelectric Test System for P-E loops. Materials included ferric nitrate, bismuth nitrate, lead acetate, titanium iso-propoxide, bismuth oxide, iron oxide, lead oxide, titanium oxide, acetic acid, 2-methoxyethanol, and acetone.

4：Experimental Procedures and Operational Workflow:

For Sol-gel method, precursors were mixed in solvents, stirred, dried to gel, calcined at 923 K, pressed into pellets, and sintered at 1098-1123 K. For Single-step method, oxides were mixed, pressed, and sintered similarly. XRD was performed with Rietveld refinement, SEM for morphology, dielectric measurements from 80-700 K and 10^2-10^6 Hz, and ferroelectric loops at room temperature.

5：Data Analysis Methods:

Rietveld refinement using X-pert High Score plus software, Scherrer's equation for crystallite size, Arrhenius equation for ac conductivity activation energies, and analysis of dielectric and ferroelectric properties.