Used as a catalyst in organic synthesis, particularly in coupling reactions such as Ullmann and Glaser reactions. Employed in the production of pigments for glass, ceramics, and paints due to its ability to impart blue or green colors. Applied in electroplating processes to deposit copper coatings on various substrates. Utilized in wood preservation to protect against fungal decay and insect damage. Serves as a reagent in analytical chemistry for detecting and quantifying certain compounds. Also found in some industrial processes for desulfurization of gases.