1：Experimental Design and Method Selection:

The study involves the construction of a Mo2C@C/g-C3N4 heterostructure where carbon nanosheets serve as a binder between Mo2C and g-C3N4. The methodology includes hydrothermal processes followed by thermal treatment for the synthesis of Mo2C@C and its deposition onto g-C3N4 nanosheets.

2：The methodology includes hydrothermal processes followed by thermal treatment for the synthesis of Mo2C@C and its deposition onto g-C3N4 nanosheets. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Samples include bulk g-C3N4, g-C3N4 nanosheets, Mo2C@C, and Mo2C/CN composites. Data sources include characterization techniques such as TEM, HRTEM, XRD, XPS, UV-vis absorption spectroscopy, and photocatalytic measurements.

3：List of Experimental Equipment and Materials:

Equipment includes a Bruker D2 Phaser for XRD, FEI Quanta 250 for SEM, JEOL JEM2100 for TEM, and a V-670 spectrophotometer for UV-vis absorption spectroscopy. Materials include dicyandiamide, (NH4)6Mo7O24·4H2O, glucose, and triethanolamine.

4：Experimental Procedures and Operational Workflow:

The procedure involves the synthesis of g-C3N4 nanosheets, Mo2C@C via hydrothermal and thermal treatments, and the assembly of Mo2C@C/g-C3N4 heterostructures. Photocatalytic H2 evolution measurements are conducted under visible-light irradiation.

5：Data Analysis Methods:

Data analysis includes PL spectra, transient photocurrent responses, EIS, and transient fluorescence decay spectra to understand charge carrier dynamics.