The spectroscopy of InSe nanoparticles

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Physics

Background:

• Indium Selenide (InSe) is a layered semiconductor with potential applications in electronics and optoelectronics.
• Understanding quantum confinement effects in low-dimensional InSe is crucial for tailoring its properties.

Purpose of the Study:

• To synthesize and characterize Indium Selenide (InSe) nanoparticles of varying sizes.
• To investigate the structural and optical properties of these nanoparticles, focusing on quantum confinement.

Main Methods:

• Synthesis of InSe nanoparticles using organometallic precursors.
• Characterization via transmission electron microscopy (TEM) and electron diffraction.
• Optical spectroscopy (absorption and fluorescence) to probe electronic properties.

Main Results:

• Successfully synthesized InSe nanoparticles exhibiting a two-dimensional disk morphology, composed of single tetralayer sheets.
• Observed significant quantum confinement effects along the z-axis and in the x,y plane for smaller particles.
• Absorption spectra showed a reversal of direct and indirect transitions in larger particles due to z-axis confinement.
• Strong, polarized fluorescence was detected, correlating with the bulk InSe band structure.

Conclusions:

• The synthesized InSe nanoparticles are single tetralayer 2D disks.
• Quantum confinement significantly modifies the electronic and optical properties of InSe nanoparticles.
• The observed phenomena can be explained by the band structure of bulk Indium Selenide.