Tailoring of morphology and crystal structure of CdSe nanostructures by controlling the ratio of triethylenetetraamine and water in their mixed solution

The morphological manipulation, structural characterization, and optical properties of different CdSe nanocrystals were reported. Several different CdSe nanostructures, including nanowires, tetrapod crystals, and nanoparticles were grown by varying the volume ratio of triethylenetetraamine (TETA) and water (WA) in their mixed solution. By manipulating the growth driving force (i.e., the degree of supersaturation) and kinetics of the process (i.e., growth rate), the morphology and crystal structure of CdSe nanocrystals can be tailored. Growth driving force changed their morphology from nanowires to tetrapod structures and from the latter structure to nanoparticles. Moreover, kinetics of the process altered their crystal structure from wurtzite to zinc blende. The optical property of CdSe nanocrystals was investigated using UV-vis spectroscopy. The absorption edge of CdSe nanostructures showed a blue shift. CdSe nanocrystals prepared under optimized conditions showed good microstructural and optical properties for solar cell application.