title: Hydrazine-mediated construction of nanocrystal self-assembly materials.
abstract: Self-assembly is the basic feature of supramolecular chemistry, which permits to integrate and enhance the functionalities of nano-objects. However, the conversion of self-assembled structures to practical materials is still laborious. In this work, on the basis of studying one-pot synthesis, spontaneous assembly, and in situ polymerization of aqueous semiconductor nanocrystals (NCs), NC self-assembly materials are produced and applied to design high performance white light-emitting diode (WLED). In producing self-assembly materials, the additive hydrazine (N2H4) is curial, which acts as the promoter to achieve room-temperature synthesis of aqueous NCs by favoring a reaction-controlled growth, as the polyelectrolyte to weaken inter-NC electrostatic repulsion and therewith facilitate the one-dimensional self-assembly, and in particular as the bifunctional monomers to polymerize with mercapto carboxylic acid-modified NCs via in situ amidation reaction. This strategy is versatile for mercapto carboxylic acid-modified aqueous NCs, for example CdS, CdSe, CdTe, CdSe(x)Te(1-x), and Cd(y)Hg(1-y)Te. Because of the multisite modification with carboxyl, the NCs act as macromonomers, thus producing cross-linked self-assembly materials with excellent thermal, solvent, and photostability. The assembled NCs preserve strong luminescence and avoid unpredictable fluorescent resonance energy transfer, the main problem in design WLED from multiple NC components. These advantages allow the fabrication of NC-based WLED with high color rendering index (86), high luminous efficacy (41 lm/W), and controllable color temperature.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, PR China.
authors.forename: Ding
authors.initials: D
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.forename: Min
authors.initials: M
authors.lastname: Lin
authors.forename: Xinyuan
authors.initials: X
authors.lastname: Bu
authors.forename: Xintao
authors.initials: X
authors.lastname: Luo
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Bai
authors.initials: B
authors.lastname: Yang
keywords: aqueous synthesis; nanocomposites; quantum dots; self-assembly materials; white light-emitting diode