Synthesis, characterization and optical properties of ligand-protected indium nanoparticles

Unlike silver and gold, indium has material properties that enable strong resonances extended up to the ultraviolet. This extended response, combined with low cost, and ease of synthesis process, makes indium a highly promising material for applications. In this work, we have synthesized ligand-protected indium nanoparticles by a metal reduction method. Powder X-ray diffraction and EDX analyses are consistent with the presence of metallic indium in the nanoparticles. Ligand binding was proven by IR spectroscopy and TGA experiments. TEM analyses reveal that the particle size ranges from 6.3 to 4.8 nm. Optical measurements show that the absorption maximum is red shifted as the particle size decreases.