Two-Dimensional Indium Selenide for Sulphur Vapour Sensing Applications

Abstract

Surface-to-volume ratio in two-dimensional (2D) materials highlights among their characteristics as an inherent and intrinsic advantage taking into account their strong sensitivity to surface effects. For this reason, we have proposed in this work micromechanically exfoliated 2D nanosheets of InSe as an optical vapour sensor. As a proof of concept, we used 2-mercaptoethanol as the chemical analyte in vapour phase to monitor the change of the InSe photoluminescence (PL) before and after exposure to the analyte. For short vapour exposure times (at low analyte concentration), we found a PL enhancement of InSe nanosheets attributed to the surface localization of Se defects. For long vapour exposure times (or higher concentrations) a PL reduction is observed, probably due to the diffusion of molecules within the nanosheet. These results confirm the capability of 2D InSe as a photoluminescent sensor of vapours, because of its sensitivity to surface passivation or volume diffusion of molecules.

Tunable electronic and magnetic properties of Cr2Ge2Te6 monolayer by organic molecular adsorption

“…Since graphene was discovered in 2004 [1], two-dimensional (2D) materials exhibit novel properties [2][3][4][5], which have great potential applications in photoelectric [6,7] and thermal [8,9] devices, sensing [10] and battery [11]. For example, MoS 2 monolayer shows excellent electronic properties with a direct band gap of about 1.62 eV [12].…”

Molecularly Imprinted Silver Nanocomposites for Explosive Taggant Sensing

“…22 Other approaches involve optical properties of nanomaterials such as absorbance (colorimetric) and fluorescence/photoluminescence (PL) and their responses for explosive detection. 3,23 Parkin and coworkers 24 reported a multicolored fluorescent array of three different functionalized CdSe/ZnS quantum dots (QDs) in solution. The PL of QDs is quenched in the presence of DNT, TNT, RDX, and PETN in water with a limit of detection (LOD) of <0.2 μg/mL.…”

“…NO 2 -containing compounds show specific redox properties depending on the composition. , Guo et al report an electrochemical sensor based on porphyrin-functionalized graphene to detect ultratrace nitroaromatic explosives, demonstrating high sensitivity, good reproducibility, and selectivity . Other approaches involve optical properties of nanomaterials such as absorbance (colorimetric) and fluorescence/photoluminescence (PL) and their responses for explosive detection. , Parkin and co-workers reported a multicolored fluorescent array of three different functionalized CdSe/ZnS quantum dots (QDs) in solution. The PL of QDs is quenched in the presence of DNT, TNT, RDX, and PETN in water with a limit of detection (LOD) of <0.2 μg/mL.…”