Copper selenide nanoparticles are important materials with desirable properties for a broad scope of applications. Copper selenides are additionally known to adopt several different crystal structures and compositions. Here, we report the direct solution-phase synthesis of colloidal Cu2-xSe nanoparticles that adopt a structure distinct from other known copper selenide phases. This Cu2-xSe phase was determined to be structurally related to weissite Cu2-xTe, which is a layered compound containing alternating Cu-rich and Cu-deficient layers sandwiching distorted hexagonal layers of chalcogen atoms. When the weissite-like Cu2-xSe nanoparticles were annealed in solution, they converted to the more stable cubic berzelianite phase, indicating that they are metastable. Optical characterization of the weissite-like Cu2-xSe nanoparticles showed a broad plasmon absorption band centered around 1550 nm, and the position of this absorption band shifted only slightly when subjected to reductive and oxidative conditions.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Chemistry