From (Cd2Se2)(pa) (pa = propylamine) hybrid precursors to various CdSe nanostructures: structural evolution and optical properties

Abstract

Nanostructural evolution of II–VI semiconductors emerges as a hot research field because it offers a novel route for the synthesis of functional semiconductor nanomaterials. Here, we report a “top-down” process of structural evolution from two dimensional Cd₂Se₂(pa) hybrid structures to zero- or one- dimensional CdSe nanostructures. We firstly synthesized the Cd₂Se₂(pa) hybrid by a facile solvothermal reaction and determined the hybrid crystal structure through the Rietveld refinement based on the PXRD data. The (Cd₂Se₂)(pa) hybrid consists of [Cd₂Se₂] slabs sandwiched by coordinated n-propylamine layers. Then, we used this hybrid as a precursor to explore the “top-down” fabrication process of structural evolution from two dimensional layered structures to zero- or one- dimensional nanocrystals. It has been shown that various CdSe nanostructures including lamellar structures, nanoparticles, nanowires, and nanorods can be obtained through the pyrolysis of (Cd₂Se₂)(pa) hybrid precursor under different conditions. It is worth mentioning that the oriented attachment of nanoparticles has been observed during the pyrolysis process. Additionally, the variation of optical properties with structural evolution has been investigated in detail.