1：Experimental Design and Method Selection:

The study employed a combination of bio-reduction, sol-deposition, and calcination to synthesize g-C3N4-SiC-Pt composite photocatalysts. The design rationale was to create a heterojunction between g-C3N4 and SiC with Pt nanoparticles to enhance charge separation and photocatalytic activity. Theoretical models included band structure analysis and heterojunction formation mechanisms.

2：Sample Selection and Data Sources:

Samples included g-C3N4-bulk, g-C3N4-nanosheet, SiC, and various composite photocatalysts (e.g., g-C3N4-SiC, g-C3N4-SiC-Pt) with different mass ratios and calcination temperatures. Materials were sourced from Sinopharm Chemical Reagent Co., Ltd., Aladdin Reagents (Shanghai) Co. Ltd., and Xiamen Peony Perfume & Chemicals Industry Co. Ltd.

3：List of Experimental Equipment and Materials:

Equipment included transmission electron microscope (Tecnai F30, FEI), scanning electron microscope (Sigma, ZEISS), X-ray diffractometer (Rigaku), FTIR spectrometer (Nicolet N6700), UV-visible spectrophotometer (Varian Cary 5000), BET surface area analyzer (Tristar II 3020), fluorescence spectrophotometer (F-7000, Hitachi), thermogravimetric analyzer (SDT Q600), photocatalytic reaction system (CEL-SPH2N, Beijing Education Au-light Co. Ltd), xenon lamp (300 W), optical power meter (CEL-NP2000-2), and gas chromatography (GC-9160, Shanghai OH). Materials included H2PtCl6·6H2O, isopropanol, triethanolamine, melamine, SiC, Cinnamomum camphora leaf extract, and deionized water.

4：Experimental Procedures and Operational Workflow:

Synthesis involved dispersing g-C3N4-nanosheet and SiC in deionized water, sonication, mixing, evaporation, grinding, and calcination at specified temperatures (e.g., 250-550 °C). Pt-sol was prepared by adding H2PtCl6·6H2O to Cinnamomum camphora extract, reacting at 90 °C, and cooling. For g-C3N4-SiC-Pt, Pt-sol was added to the mixed solution, stirred, evaporated, ground, and calcined. Photocatalytic tests involved dispersing photocatalyst in triethanolamine solution, bubbling with N2, irradiating with xenon lamp (λ ≥ 420 nm), and measuring H2 production via gas chromatography.

5：Data Analysis Methods:

Data analysis included characterization techniques (TEM, SEM, XRD, FTIR, UV-vis DRS, BET, PL, TGA, XPS) to assess morphology, structure, optical properties, surface area, and chemical states. Photocatalytic activity was evaluated based on hydrogen evolution rate and quantum efficiency, calculated using equations provided in the paper. Statistical analysis involved comparing performance across different samples and conditions.