Used as a precursor in the synthesis of thulium-containing materials for specialized optical devices and lasers. Employed in research for doping in solid-state lasers and luminescent materials due to its unique emission properties in the near-infrared range. Applied in the preparation of catalysts for organic reactions and in the development of phosphors for display technologies. Also utilized in scientific studies involving lanthanide chemistry and material science where a soluble thulium source is required.