A facile strategy of using MoS₂ quantum dots for fluorescence-based targeted detection of nitrobenzene

Abstract

We present a simple approach for producing photoluminescent MoS2 quantum dots (QDs) using commercial MoS2 powder as a precursor along with NaOH and isopropanol.

Hydrothermal Synthesis of Fluorescent Functionalized MoS2 Quantum Dots for Heavy Metal Detection

“…At higher concentrations (>10–1000 μM) the interaction between Cu 2+ and MoS 2 QDs cannot be exclusively ascribed to the Stern–Volmer model. Therefore, it can also be assumed that other types of interactions beyond the formation of complexes (static quenching) ,,, or/and electrostatic interactions also participate in the quenching process at higher concentrations (>10–1000 μM). Additionally, from 10 to 1000 μM, the PL emission peak red-shifted from ≈425 to ≈437 nm for all MoS 2 QDs in the presence of Cu 2+ , which may indicate the formation of large particle size.…”

“…The literature reports that electrons pairs of functional surface groups, such as −CN and −NH, can promote the complex formation between MoS 2 QDs and Fe 3+ . Moreover, the contribution of dynamic quenching, which is related to the time-resolved lifetime PL, together with inner filter effect (IFE) is also reported in some cases, and the total quenching may result from multiple quenching mechanism contributions …”

“…The synthesis of QDs employing ultrasonic exfoliation of bulk MoS 2 can also lead to the surface functionalization of MoS 2 QDs by introducing sulfate bonds. 33 Carboxylic-(−COOH), amine-(−NH 2 ), and thiol-functionalized (−SH) MoS 2 QDs obtained by the hydrothermal route have demonstrated that MoS 2 QDs' functionalization surface can modify the fluorescent absorption and emission as well as the selectivity and affinity toward heavy metals detection. 14 MoS 2 /COOH QDs have demonstrated PL quenching for Co 2+ , MoS 2 /NH 2 for Cd 2+ , and MoS 2 /SH for Pb 2+ , demonstrating selectivity to specific metals ions as a consequence of surface modification groups.…”

“…It was shown that the increment of iodine led to a red-shift emission from blue to green. The synthesis of QDs employing ultrasonic exfoliation of bulk MoS 2 can also lead to the surface functionalization of MoS 2 QDs by introducing sulfate bonds . Carboxylic- (−COOH), amine- (−NH 2 ), and thiol-functionalized (−SH) MoS 2 QDs obtained by the hydrothermal route have demonstrated that MoS 2 QDs’ functionalization surface can modify the fluorescent absorption and emission as well as the selectivity and affinity toward heavy metals detection .…”

A Review of Top‐Down Strategies for the Production of Quantum‐Sized Materials

“…Cyraic et al introduced a cost‐effective platform for the production of MoS 2 QSs by the ion intercalation without any external stimuli. [ 193 ] The intercalation of Na + ions into MoS 2 layers and subsequent oxidative cutting reaction resulted in the formation of MoS 2 QSs (with an average lateral size of 3.8 nm). However, the intrinsic properties of the material could be changed under the action of ions.…”