TY - JOUR
T1 - Phase determination of zinc selenide nanocrystals depending on the ligand species of precursor complexes
AU - Omata, Takahisa
AU - Uesugi, Hideo
AU - Kita, Masao
N1 - Funding Information:
This study was supported in part by Grants-in-Aid for Scientific Research (B) from the Japan Society for the Promotion of Science (Grant nos. 20360299 and 23360287 ).
PY - 2014/5/15
Y1 - 2014/5/15
N2 - The two polytypes of ZnSe nanocrystals (NCs), the wurtzite (WZ) and zincblende (ZB) phases, were synthesized in hot organic solutions using zinc acetate as the zinc monomer with oleic acid and oleylamine as ligands. The growth rate, number and size of NCs during the growth stage were evaluated based on the X-ray diffraction profiles, high-resolution transmission electron microscope observations and optical absorption spectra. Experimental results suggested that in these systems, the phase that appeared was not determined during the growth stage but during the nucleation stage. High supersaturation during the nucleation stage resulted in the thermodynamically stable ZB phase, while low supersaturation resulted in the metastable WZ phase. The reason why supersaturation during nucleation determined the phase was discussed on the basis of the size of the critical nucleus influenced by the total free energy change in the system during nucleation.
AB - The two polytypes of ZnSe nanocrystals (NCs), the wurtzite (WZ) and zincblende (ZB) phases, were synthesized in hot organic solutions using zinc acetate as the zinc monomer with oleic acid and oleylamine as ligands. The growth rate, number and size of NCs during the growth stage were evaluated based on the X-ray diffraction profiles, high-resolution transmission electron microscope observations and optical absorption spectra. Experimental results suggested that in these systems, the phase that appeared was not determined during the growth stage but during the nucleation stage. High supersaturation during the nucleation stage resulted in the thermodynamically stable ZB phase, while low supersaturation resulted in the metastable WZ phase. The reason why supersaturation during nucleation determined the phase was discussed on the basis of the size of the critical nucleus influenced by the total free energy change in the system during nucleation.
KW - A1: Nanostructures
KW - B1: Inorganic compounds
KW - B1: Nanomaterials
KW - B2: Phosphors
KW - B2: Semiconducting II-VI materials
UR - http://www.scopus.com/inward/record.url?scp=84896774329&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84896774329&partnerID=8YFLogxK
U2 - 10.1016/j.jcrysgro.2014.02.019
DO - 10.1016/j.jcrysgro.2014.02.019
M3 - Article
AN - SCOPUS:84896774329
VL - 394
SP - 81
EP - 88
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
SN - 0022-0248
ER -