Size, Shape-Dependent Growth of Semiconductor Heterostructures Mediated by Ag₂Se Nanocrystals as Seeds

Size- and shape-controllable Ag₂Se-ZnS nanorods (NRs) and nanowires (NWs) have been synthesized successfully by the solution–liquid–solid (SLS) method. By using Ag₂Se nanocrystals (NCs) as seeds and catalyst, colloidal Ag₂Se-ZnS NRs and NWs with controllable diameters and lengths in ranges of 5–12 nm and 15–600 nm were successfully synthesized by altering the experimental variables, such as diameter of Ag₂Se NCs, amount of precursor, reaction time, and reaction temperature. The Ag₂Se NCs not only played a key role in the control of the shape of ZnS NCs but also influenced the crystal structure of ZnS NCs. The related surface photovoltage of heterostructured Ag₂Se-ZnS NWs have also been studied and the formation of Ag₂Se-ZnS heterostructure was confirmed. Moreover, this SLS method was successfully exploited to synthesize Ag₂S-ZnS heterostructures