1：Experimental Design and Method Selection

The study involves the synthesis of ZnO nanoparticles films by sol-gel process and GaxSe10-x material by mechanical alloying. The performance of solar cells was evaluated using current-voltage measurements, impedance spectroscopy, and capacitance-voltage profiling.

2：Sample Selection and Data Sources

Se (Aldrich, purity > 99.99%) and Ga (Aldrich, purity > 99.95%) were used as starting materials for the synthesis of GaxSe10-x alloys. Transparent electrodes were prepared from thin film coatings of fluorine-doped tin oxide (FTO) on glass.

3：List of Experimental Equipment and Materials

Fritsch Pulverisette 7 Premium planetary ball mill, Shimadzu XRD-7000 X-ray diffractometer, FEI Phenom scanning electron microscope, Perkin Elmer Lambda 1050 UV–vis spectrophotometer, Bruker DektakXT surface profiler, Oriel Solar simulator, Keithley 6487 picoammeter, Agilent 4284A LCR meter.

4：Experimental Procedures and Operational Workflow

ZnO nanoparticles solution was deposited over the FTO by spin-coating. The active layer was thermally evaporated on top of the FTO/ZnO NPs substrates. Gold back contacts were deposited by thermal evaporation. The crystalline phase of GaxSe10-x active layer was obtained by thermal treatment.

5：Data Analysis Methods

The electrical characterization of solar cell devices was performed by current density – voltage measurements under AM 1.5 G 100 mW/cm2 irradiance or darkness. Capacitance and impedance measurements were performed with an Agilent 4284A LCR meter.