Solvo-thermal synthesis and characterization of indium selenide nanocrystals

Zinc-blende-type cubic InSe and β-In₂Se₃ crystallites were synthesized using the solvo-thermal method in this study. The crystalline structure, electronic and optical characterization of indium selenide particles were investigated using transmission electron microscopy (TEM), X-ray diffractometer (XRD), UV-visible absorbance spectra. It was observed that the dominant crystalline structure of samples synthesized at 180°C for 1.5-48 h is zinc-blende-type cubic InSe phase with lattice parameter of about 0.573 nm. As the reaction temperature was raised to 200°C, the zinc-blende-type cubic InSe phase diminished and the β-In₂Se₃ phase was produced. The zinc-blende-type cubic InSe phase band gap is about 1.68 eV. These synthesized compounds provide promising candidates for solar cell applications.