1：Experimental Design and Method Selection:

The study involved synthesizing TiO2/CNTs-filters using chemical vapor deposition (CVD) for CNTs growth on nickel foam modified with an Al2O3 barrier layer, followed by dip-coating with TiO2 nanoparticles (Degussa P25). Filtration and photocatalytic performance tests were conducted to evaluate efficiency and degradation rates.

2：5). Filtration and photocatalytic performance tests were conducted to evaluate efficiency and degradation rates. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Nickel foams (thickness ~3 mm, PPI 110, Ni≥99.9 wt.%) were used as substrates. Oleic acid aerosols served as mock oil mist for testing.

3：9 wt.%) were used as substrates. Oleic acid aerosols served as mock oil mist for testing. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Equipment included SEM (FEI Quanta 200), TEM (FEI Tecnai G20), contact angle goniometer (Powereach JC2000D), pore-size distribution analyzer (GaoQ PSDA-20), ELPI (DEKATI), pressure transmitter (Asmik MIK-9600D), electron balance (Sartorius), UV light (Cnlight, 15 W, 253.7 nm), digital radiometer (Sentry ST-512), and type K thermocouple. Materials included aluminium isopropoxide, xylene, ferrocene, Degussa P25 TiO2, hydrochloric acid, and oleic acid.

4：7 nm), digital radiometer (Sentry ST-512), and type K thermocouple. Materials included aluminium isopropoxide, xylene, ferrocene, Degussa P25 TiO2, hydrochloric acid, and oleic acid. Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: Synthesis involved CVD growth of CNTs at 800°C with xylene/ferrocene solution, purification with HCl, dip-coating with TiO2 suspension, and calcination. Filtration tests measured pressure drop and efficiency using oleic acid aerosols; photocatalytic tests measured mass loss under UV irradiation.

5：Data Analysis Methods:

Data were analyzed using equations for pressure drop (proportional to face velocity), filtration efficiency, quality factor, and degradation rates, with comparisons to HEPA filters.