Synthesis of In2S3 microspheres using a template-free and surfactant-less hydrothermal process and their visible light photocatalysis

Abstract

Indium sulfide (In₂S₃) microspheres of (β-) tetragonal phase were synthesized by varying the indium precursors using a template-free and surfactant-less hydrothermal process at 150 °C. The as-synthesized samples were found to be crystalline and phase pure as confirmed by X-ray diffraction and X-ray photoelectron spectroscopy studies, respectively. Indium precursors play an important role in controlling the shape of the building blocks, i.e. nanoflakes or nanobricks, of In₂S₃ microspheres. The photocatalytic activity of as-synthesized In₂S₃ microspheres was tested for the degradation of methylene blue and crystal violet in the presence of visible light produced by an incandescent lamp. The terephthalic acid test using photoluminescence spectroscopy shows hydroxyl radicals as active species for the degradation of organic contaminants. Repeat photocatalysis measurements suggest the high stability of In₂S₃ microspheres without a change in their morphology and phase.