1：Experimental Design and Method Selection:

The study involved the synthesis of a WO3–TiO2 vertical heterojunction via a hydrolysis–hydrothermal method, characterization using various techniques, and evaluation of photocatalytic activity.

2：Sample Selection and Data Sources:

TiO2 nanosheets and WO3 nanosheets were synthesized and characterized. The photocatalytic activity was evaluated using E. coli disinfection as a model.

3：List of Experimental Equipment and Materials:

Equipment included X-ray diffractometer, FTIR spectrometer, Raman spectrometer, XPS spectrometers, SEM, TEM, UV-vis spectrophotometer, fluorescence spectrophotometer, and electrochemical workstation. Materials included titanium(IV) butoxide, hydrofluoric acid, Na2WO4, and others.

4：Experimental Procedures and Operational Workflow:

The synthesis involved adsorption of WO4^2? ions onto TiO2 nanosheets, hydrolysis to H2WO4 nanosheets, and hydrothermal treatment to form WO3 nanosheets. Photocatalytic activity was assessed through ROS generation and E. coli disinfection.

5：Data Analysis Methods:

Data analysis included XRD, FTIR, Raman spectroscopy, XPS, SEM, TEM, UV-vis DRS, PL spectra, and electrochemical measurements.