Selenium quantum dots: Preparation, structure, and properties

Abstract

An interesting class of low-dimensional nanomaterials, namely, selenium quantum dots (SeQDs), which are composed of nano-sized selenium particles, is reported in this study. The SeQDs possess a hexagonal crystal structure. They can be synthesized in large quantity by ultrasound liquid-phase exfoliation using NbSe 2 powders as the source material and N-Methyl-2-pyrrolidone (NMP) as the dispersant. During sonication, the Nb-Se bonds dissociate; the SeQDs are formed, while niobium is separated by centrifugation. The SeQDs have a narrow diameter distribution from 1.9 to 4.6 nm and can be dispersed with high stability in NMP without the need for passivating agents. They exhibit photoluminescence properties that are expected to find useful applications in bioimaging, optoelectronics, as well as nanocomposites.

Eco‐Friendly Approach to Synthesize Selenium Nanoparticles: Photocatalytic Degradation of Sunset Yellow Azo Dye and Anticancer Activity

“…The optical property of the synthesized Se‐NPLs was evaluated by recording photoluminescence spectra (PL). As the excitation wavelength was changed to a longer wavelength, the emission peak gradually red‐shifted …”

Tantalum disulfide quantum dots: preparation, structure, and properties

“…It can be seen that a higher excitation energy (λ Ex = 320 nm) led to a larger Stokes shift (71 nm), whereas a lower excitation energy (λ Ex = 460 nm) resulted in a smaller Stokes shift (59 nm). The difference in Stokes shift is probably due to the size distribution of the prepared QDs, which has also been observed from Se QDs and Te QDs [27,28]. Comparing the PL and PLE peaks, Fig.…”

“…2e and was deconvoluted into components, such as Ta 4f 7/2 (23.2 eV), Ta 4f 5/2 (25.6 eV), and Ta 4f 7/2 (27.2 eV). The Ta 4f 7/2 peak at 27.2 eV is associated with oxidized tantalum [24,25]; oxidation has also been observed in other QDs [26][27][28]. and A 1g modes relate to the in-plane and out-of-plane vibration respectively [29].…”

Recent Advances in Semiconducting Monoelemental Selenium Nanostructures for Device Applications

“…Nanoparticles are particles with the size range of 1-100 nm, which have drawn attractive scientific attention due to their versatile potential applications in optical, electronic, and biomedical fields. [60][61][62][63][64][65][66][67][68][69] Qian et al [29] reported that Se nanoparticles with an average diameter of ≈3 nm and a narrow size distribution, were successfully fabricated in large quantities by liquid-phase exfoliation using NbSe 2 powders as the source material and N-methyl-2-pyrrolidone (NMP) as the dispersant (Figure 2a). High-resolution transmission electron microscopy (HRTEM) image (Figure 2a, inset) reveals that the as-prepared Se nanoparticles have the characteristic of crystalline lattice planes and the d-spacing is 0.23 nm.…”

“…[47] Chiou et al [54] reported that single-crystalline Se nanorods, was, Reproduced with permission. [29] Copyright 2017, AIP Publishing. b) TEM image of the samples prepared from ethanol solution of H 2 SeO 3 .…”