1：Experimental Design and Method Selection:

The study employs an amino acid guiding strategy for the synthesis of Au nanocrystals–metal selenide hybrid nanostructures. The method involves adjusting the initial concentration of Pb2+ to manipulate the symmetry of PbSe shells on Au nanorods.

2：Sample Selection and Data Sources:

Au nanorods are used as initial materials. The synthesis involves the deposition of an amorphous Se shell on Au nanorods, followed by the formation of metal selenide nanoshells using Au@Se NRs as seeds and Se sources.

3：List of Experimental Equipment and Materials:

Chemicals include chloroauric acid, silver nitrate, glycine acid, cetyltrimethylammonium-bromide, sodium borohydride, L-ascorbic acid, sodium hydrate, hydrochloric acid, tetrabutyl titanate, sodium sulfite anhydrous, sodium sulfide nonahydrate, selenium dioxide, lead acetate, bismuth nitrate, and cadmium acetate. Equipment includes transmission electron microscopy (TEM), high-angle annular dark-field scanning TEM (HAADF-STEM), high-resolution TEM (HRTEM), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Vis spectrophotometer, and photoelectrochemical measurement setup.

4：Experimental Procedures and Operational Workflow:

The synthesis involves the growth of Au NRs, Au@Se NRs, and Au–PbSe hybrid NRs. The morphology and structure characterizations are performed at each growth stage. Photoelectrochemical tests are conducted on TiO2 NWs photoanodes sensitized by Au–PbSe hybrid NRs.

5：Data Analysis Methods:

The optical properties of the hybrid nanostructures are analyzed using extinction spectra. Photoelectrochemical performances are evaluated through photocurrent experiments and electrochemical impedance spectroscopy (EIS).