title: Phosphine-Free Synthesis of Metal Chalcogenide Quantum Dots by Directly Dissolving Chalcogen Dioxides in Alkylthiol as the Precursor.
abstract: Semiconductor quantum dots (QDs) are competitive emitting materials in developing new-generation light-emitting diodes (LEDs) with high color rendering and broad color gamut. However, the use of highly toxic alkylphosphines cannot be fully avoided in the synthesis of metal selenide and telluride QDs because they are requisite reducing agents and solvents for preparing chalcogen precursors. In this work, we demonstrate the phosphine-free preparation of selenium (Se) and tellurium (Te) precursors by directly dissolving chalcogen dioxides in the alkylthiol under the mild condition. The chalcogen dioxides are reduced to elemental chalcogen clusters, while the alkylthiol is oxidized to disulfides. The chalcogen clusters further combine with the disulfides, generating dispersible chalcogen precursors. The resulting chalcogen precursors are suitable for synthesizing various metal chalcogenide QDs, including CdSe, CdTe, Cu2Te, Ag2Te, PbTe, HgTe, and so forth. In addition, the precursors are of high reactivity, which permits a shorter QD synthesis process at lower temperature. Owing to the high quantum yield (QYs) and easy tunability of the photoluminescence (PL), the as-synthesized QDs are further employed as down-conversion materials to fabricate monochrome and white LEDs.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Dong
authors.initials: D
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xin
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Zhaoyu
authors.initials: Z
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Ze
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Jianyou
authors.initials: J
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Chunwei
authors.initials: C
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Yi
authors.identifier: http://orcid.org/0000-0003-0548-6073
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Bai
authors.identifier: http://orcid.org/0000-0002-3873-075X
authors.initials: B
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
authors.forename: Hao
authors.identifier: http://orcid.org/0000-0002-2373-1100
authors.initials: H
authors.lastname: Zhang
keywords: chalcogen precursors; light-emitting diodes; metal selenide/telluride nanocrystals; phosphine-free synthesis; quantum dots