1：Experimental Design and Method Selection:

The overall experimental design involved using the diffusion embedding of ready-made semiconductor nanoparticles (CdSe quantum dots and nanocrystalline silicon) into a porous fibrous matrix of F42 copolymer in a supercritical CO2 medium. The method included swelling the polymer in SC-CO2 to increase internal free volume, efficient transport of nanoparticles due to low viscosity of SC-CO2, and compression after pressure release to isolate nanoparticles in the polymer matrix. Cold or hot pressing was used at the final stage to create transparent and mechanically robust film composites.

2：Sample Selection and Data Sources:

Initial samples were fibrous F42 copolymer porous films (1 × 1 cm, 2–3 mm thick) obtained by electroforming a copolymer with 85% tetrafluoroethylene and 15% vinylidene fluoride. Colloidal solutions of CdSe quantum dots (5 mg/mL in toluene, Sigma-Aldrich) and nanocrystalline silicon particles (in hexane) were used as nanoparticle sources. Nanoparticles were synthesized via disproportionation reaction from silicon monoxide.

3：List of Experimental Equipment and Materials:

Equipment included a supercritical CO2 chamber (pressure 18–20 MPa, temperature 50°C), pressing apparatus (for cold pressing at room temperature and hot pressing at 140°C with pressures of 7–20 MPa), USB4000 fiber spectrometer (Ocean Optics), KLM-405-200 semiconductor laser (Russia), Phenom ProX desktop scanning electron microscope (SEM, Phenom-World BV), Charge Reduction Sample Holder, metal substrates (Agar Scientific), conductive carbon adhesive tape, graphite suspension, and optical fibers with short-focus lenses.

4：Experimental Procedures and Operational Workflow:

Porous F42 films were maintained in colloidal nanoparticle solutions, then treated in SC-CO2 medium at 18–20 MPa and 50°C for 1 hour. Pressure was lowered to atmospheric over 30 minutes while maintaining temperature above 31°C. Impregnated films were pressed (cold for nc-Si at room temperature and 20 MPa, hot for CdSe at 140°C and 7 MPa) to enhance transparency and mechanical properties. Photoluminescence spectra were measured using a USB4000 spectrometer with excitation from a 405 nm laser, and SEM images were recorded at accelerating voltages of 5, 10, and 15 kV.

5：Data Analysis Methods:

Photoluminescence spectra were analyzed for intensity changes and band shifts under laser exposure. SEM images were used to study surface morphology and porosity. Kinetic curves of photoluminescence intensity decay or growth were approximated using exponential or linear functions, and comparisons were made with previous studies on similar composites.