1：Experimental Design and Method Selection:

The MoS2(1?x)Se2x nanostructures were synthesized via a hydrothermal method. The photodetector was fabricated using the synthesized material as a light-sensitive material.

2：Sample Selection and Data Sources:

Samples were prepared with different selenium contents by varying the addition ratio of selenium powder and thiourea during the synthesis process.

3：List of Experimental Equipment and Materials:

Hydrazine hydrate, ammonium molybdate tetrahydrate, thiourea, hydrochloric acid, selenium powder, and N-methyl-2-pyrrolidone were used. Equipment included a stainless steel autoclave, scanning electron microscope (SEM), X-ray diffractometer (XRD), UV-vis spectrophotometer, and Keithley's 2612B semiconductor characterization system.

4：Experimental Procedures and Operational Workflow:

The synthesis involved dissolving chemicals in a mixed solution, transferring to an autoclave, and heating. The photodetector was fabricated by filtering the material through an organic filter membrane and depositing metallic Cu interdigital electrodes.

5：Data Analysis Methods:

The performance of the photodetector was evaluated by measuring photocurrent and responsivity under different wavelengths and power densities.