Aqueous synthesis of highly luminescent CdSe quantum dots with narrow spectra using hydrazine hydrate reduction selenium

Abstract

Highly luminescent CdSe quantum dots (QDs) with narrow spectra were synthesised by the reaction of CdCl 2 •2.5H 2 O, Se and hydrazine hydrate (N 2 H 4 •H 2 O), respectively, in water and in the presence of 3-mercaptopropionic acid as the stabiliser. The effects of the experimental conditions, including the refluxing time and the selenium to cadmium molar ratio, on the luminescent properties of the obtained QDs have been investigated. Furthermore, the obtained QDs were characterised by UV-vis absorption spectra, photoluminescence (PL) spectra, X-ray powder diffraction and transmission electron microscopy, respectively. The results showed that the proposed method led to the formation of the cubic CdSe QDs with a narrow fluorescence full-width at half-maximum (47 nm) and a high PL quantum yield (up to 16%), respectively.

Synthesis and characterisation of CdSe QDs by using a chemical solution route

“…By using various methods or employed Cd and Se precursors, many researchers have attempted to synthesise the CdSe QDs. The CdSe QDs preparation has been recently attempted via colloidal reaction method [8], one-pot hydrothermal synthesis [9], liquid paraffin with a mixture [10], microwave and electron beam irradiation [11,12] and aqueous solution [13][14][15]. When comparing with these routes, the synthesis procedures by using an aqueous solution is exhibiting good water solubility that is simple, green and highly reproducible.…”

Pontos quânticos ambientalmente amigáveis: destaque para o óxido de zinco

“…Entre as diversas sínteses reportadas na literatura, algumas se destacam por serem reproduzidas com os precursores em solução, tendo os QDs como a fase coloidal, o que permite controlar a cristalização através dos processos de nucleação e crescimento. 60 Como exemplos da utilização destes métodos estão as sínteses de redução, 70 decomposição térmica 71 e sol-gel.…”

Facile synthesis of CdTe-based quantum dots promoted by mercaptosuccinic acid and hydrazine

“…[17][18][19][20][21][22] Though N 2 H 4 shows good performance, a large dosage of N 2 H 4 was employed in the above work (N 2 H 4 :Cd 2+ Z 800), leading to a wastage of N 2 H 4 and low stability of CdTe QDs in N 2 H 4 -rich solutions. Mercaptosuccinic acid (MSA) is a new stabilizer that shows good performance in synthesizing aqueous QDs, [23][24][25][26][27][28] but not used so widely as the classical stabilizers like thioglycolic acid (TGA) and mercaptopropionic acid (MPA).…”

“…Herein we present a green and facile method to synthesize high-quality aqueous CdTe QDs with tunable sizes by employing MSA as a stabilizer and N 2 H 4 as a growth promoter. There are reports on the application of MSA or N 2 H 4 (or some alkyl chain diamines) in the aqueous synthesis of QDs, [17][18][19][24][25][26][27][28] but to the best of our knowledge no literature has referred to the combined use of the two reagents. There was no need to prepare precursors and use N 2 to protect the reaction systems in this work.…”