摘要
The formation pathway of aqueous-phase colloidal semiconductor magic-size clusters(MSCs)remains unrevealed.In the present work,we demonstrate,for the first time,a precursor compound(PC)-enabled formation pathway of aqueous-phase CdSe MSCs exhibiting a sharp absorption peaking at about 420 nm(MSC-420).The CdSe MSC-420 is synthesized with CdCl2 and selenourea as the respective Cd and Se sources,and with 3-mercaptopropionic acid or L-cysteine as a ligand.Absorption featureless CdSe PCs form first in the aqueous reaction batches,which transform to MSC-420 in the presence of primary amines.The coordination between primary amine and Cd^(2+)on PCs may be responsible to the PC-to-MSC transformation.Upon increasing the reactant concentrations or decreasing the CdCl_(2)-ligand feed molar ratios,the Cd precursor self-assembles into large aggregates,which may encapsulate the resulting CdSe PCs and inhibit their transformation to MSC-420.The present study sheds essential light on the syntheses and formation mechanisms of nanocrystals.
基金
K.Y.thanks the National Natural Science Foundation of China(No.21773162)
the Fundamental Research Funds for the Central Universities,the Applied Basic Research Programs of Science and Technology Department of Sichuan Province(No.2020YJ0326)
the State Key Laboratory of Polymer Materials Engineering of Sichuan University(No.sklpme2020-2-09)
the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2021030)
the National Major Scientific and Technological Special Project for“Significant New Drugs Development”(No.2019ZX09201005-005-002)
M.Z.is grateful to the National Natural Science Foundation of China(No.22002099)
China Postdoctoral Science Foundation(No.2020T130441)
Sichuan University postdoctoral interdisciplinary Innovation Fund,and the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2021032).
