1：Experimental Design and Method Selection:

The Ni-doped PZT ceramic pellets were prepared via conventional solid-state reaction method with Ni content chosen in the range 0-20 at.%. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were employed to investigate the crystal structure of the prepared ceramics.

2：Sample Selection and Data Sources:

High purity raw materials PbO, ZrO2, TiO2, and NiO of Alfa Aesar (> 99.9%) were used.

3：9%) were used. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Agilent 4284A precision LCR meter, Keithley 236 source meter unit, piezometer- model PM 35, LAKE SHORE vibrating sample magnetometer.

4：Experimental Procedures and Operational Workflow:

The mixture of constituent oxide compounds was thoroughly grinded in air atmosphere using an agate mortar and pestle and later it was grinded with a little amount of alcohol to achieve high quality homogenized powder. After grinding for 4 hrs the powder was calcined in a furnace at 800°C for 5hrs. The PZT powder was again grinded to fine powder and mixed with a small amount of polyvinyl alcohol (PVA) to help in binding the powder together during pelletisation. Pellets of 12mm diameter and 1.8mm thickness, fabricated in a steel puncher dye by applying pressure of 5 ton/cm2 using a hydraulic press, were sintered at 1250oC for 2hrs in a programmable muffle furnace with temperature accuracy of ± 1oC and heating rate of 5oC/min.

5：8mm thickness, fabricated in a steel puncher dye by applying pressure of 5 ton/cm2 using a hydraulic press, were sintered at 1250oC for 2hrs in a programmable muffle furnace with temperature accuracy of ± 1oC and heating rate of 5oC/min. Data Analysis Methods:

5. Data Analysis Methods: The crystallite size was calculated using the Debye-Scherrer formula and Size-Strain Plot (SSP) method. The dielectric constant and loss were measured as a function of frequency and temperature.