Cu2SnSe3 and alloyed (ZnSe)x(Cu2SnSe3)1−x nanocrystals with a metastable zincblende and wurtzite structure

Cu2SnSe3 nanocrystals with a metastable zincblende and wurtzite structure have been successfully synthesized. The crystal structures were confirmed by means of X-ray diffraction and selected area electron diffraction. The lattice mismatch between Cu2SnSe3 and ZnSe is only 0.26%, thus homogeneously alloyed (ZnSe)x(Cu2SnSe3)1−x nanocrystals could be synthesized. The band gaps of nanocrystals can be tuned in a wide range of 2.75 to 0.92 eV; however the bowing parameter as high as 19.1 eV for alloyed (ZnSe)x(Cu2SnSe3)1−x nanocrystals was observed. These low cost and dispersible alloyed (ZnSe)x(Cu2SnSe3)1−x nanocrystals with a targeted band gap have a high potential in thin film solar cells.

► Zincblende and wurtzite Cu2SnSe3 nanocrystals have been synthesized.
► Homogeneously alloyed (ZnSe)x(Cu2SnSe3)1−x nanocrystals with a zincblende and wurtzite structure have also been prepared.
► The band gaps of alloyed nanocrystals can be tuned in a wide range of 2.75 to 0.92 eV.