1：Experimental Design and Method Selection:

The study involves synthesizing g-C3N4 nanosheets using a probe sonication-assisted liquid exfoliation method and constructing 2D-2D MoS2/g-C3N4 photocatalysts via a solvothermal method to enhance photocatalytic H2 production. Theoretical models include bandgap analysis and charge transfer mechanisms.

2：Sample Selection and Data Sources:

Bulk g-C3N4 is prepared from urea, and nanosheets are exfoliated in N-methyl pyrrolidone (NMP). MoS2 is grown on nanosheets using ammonium tetrathiomolybdate in dimethylformamide (DMF).

3：List of Experimental Equipment and Materials:

Equipment includes an ultrasonic cell disruptor (JY96-IIN, Fuxi), autoclave, photoreactor with Xenon lamp, gas chromatography (CG1690, Jiedao), SEM (Carl Zeiss Gemini Ultra55), TEM (JEOL JEM 2010), AFM (Bruker Multimode 8), XRD (Rigaku Miniflex6), BET surface area analyzer (Quantachrome Quadrasorb SI), photoluminescence spectrometer (FLS980, Edinburgh Instruments), XPS (VG ESCALAB MKII), Raman spectrometer (Horiba LabRam HR), UV-Vis spectrophotometer (Shimadzu UV-2550), electrochemical workstation (CHI660E, Shanghai Chenhua). Materials include urea, NMP, (NH4)2MoS4, DMF, TEOA, ethanol, Nafion solution, Na2SO

4：Experimental Procedures and Operational Workflow:

Bulk g-C3N4 is synthesized by heating urea at 550°C. Nanosheets are obtained by ultrasonication in NMP and centrifugation. MoS2/g-C3N4 composites are prepared via solvothermal treatment. Photocatalytic H2 production is conducted in a Pyrex reactor with TEOA solution under visible light, with H2 quantified by gas chromatography. Characterization involves SEM, TEM, AFM, XRD, BET, PL, time-resolved fluorescence, XPS, Raman, UV-Vis DRS, and electrochemical measurements.

5：Data Analysis Methods:

Data analysis includes fitting PL decay curves with exponential functions, calculating BET surface areas, determining bandgaps from UV-Vis spectra, and using electrochemical techniques for Mott-Schottky analysis.