One‐Dimensional Cuprous Selenide Nanostructures with Switchable Plasmonic and Super‐ionic Phase Attributes

Cuprous selenide nanocrystals have hallmark attributes, especially tunable localized surface plasmon resonances (LSPRs) and super‐ionic behavior. These attributes of cuprous selenide are now integrated with a one‐dimensional morphology. Essentially, Cu₂Se nanowires (NWs) of micrometer‐scale lengths and about 10 nm diameter are prepared. The NWs exhibit a super‐ionic phase that is stable at temperatures lower than in the bulk, owing to compressive lattice strain along the radial dimension of the NWs. The NWs can be switched between oxidized and reduced forms, which have contrasting phase transition and LSPR characteristics. This work thus makes available switchable, one‐dimensional waveguides and ion‐conducting channels.