1：Experimental Design and Method Selection:

The study employed a hydrothermal method for synthesizing La-doped ZnO nanowires, with structural and piezoelectric analyses using XRD, XPS, SEM, TEM, and piezoelectric measurements.

2：Sample Selection and Data Sources:

Samples included undoped and La-doped ZnO nanowires grown on Si wafers and Pt-coated polyimide films, prepared using analytical grade reagents.

3：List of Experimental Equipment and Materials:

Equipment included XRD (D/max-RC, Rigaku), FE-SEM (Nova NanoSEM 450, FEI), FE-TEM (JEM-2100F, Jeol), XPS (ESCALAB 250, Thermo Scientific), bending tester (ZBT-200, Zeetech), and nanovoltmeter (Keithley 2182A). Materials included zinc acetate dehydrate, zinc nitrate hexahydrate, hexamethylenetetramine, lanthanum(III) nitrate hexahydrate, ethyl alcohol, deionized water, N2 gas, Si wafer, Pt-coated polyimide film, and conductive tape.

4：Experimental Procedures and Operational Workflow:

A ZnO seed layer was spin-coated on a Si wafer, annealed, and then La-doped ZnO nanowires were hydrothermally synthesized at 95°C for 5 hours. Samples were washed and dried. For piezoelectric measurements, nanogenerators were fabricated on flexible substrates with conductive tape as the top electrode, and stress was applied using a bending tester to measure open-circuit voltage.

5：Data Analysis Methods:

XRD data were analyzed for lattice parameters and phase identification, XPS for surface compositions, SEM and TEM for morphology, and piezoelectric output was measured and compared between doped and undoped samples.