Novel solution synthesis of the overlooked cubic phase Cu₂GeTe₃ nanocrystals for optoelectronic devices

Herein, for the first time, we present a novel solution method for controllable synthesis of the overlooked cubic phase Cu₂GeTe₃ nanocrystals. The resulting Cu₂GeTe₃ nanocrystals are of high quality with monodispersed size and uniform shape. Optical characterization demonstrates that Cu₂GeTe₃ nanocrystals have a broad absorption in the visible to near-infrared region. Furthermore, an optoelectronic device based on Cu₂GeTe₃ nanocrystals exhibits excellent stability, reproducibility and responsivity. The novel synthetic route presented here not only can open a new avenue for fabricating Cu₂GeTe₃ nanocrystals, especially at the nanoscale, but also may further expand their applications.