1,2,3, Benzotriazole in the spotlight

Benzotriazole (BTA) is a heterocyclic compound containing three nitrogen atoms, with the chemical formula C₆H₅N₃. This aromatic compound is colorless and polar and can be used in various fields.Benzotriazole has been known for its great versatility. It has already been used as a restrainer in photographic emulsions and as a reagent for the analytical determination of silver. More importantly, it has been extensively used as a corrosion inhibitor in the atmosphere and underwater. Also, its derivatives and their effectiveness as drug precursors have been drawing attention. Besides all the application mentioned above, the BTA can be used as antifreezes, heating and cooling systems, hydraulic fluids and vapor phase inhibitors as well. 

Corrosion inhibitor

Benzotriazole is an effective corrosion inhibitor for copper and its alloys by preventing undesirable surface reactions. It is known that a passive layer, consisting of a complex between copper and benzotriazole, is formed when copper is immersed in a solution containing benzotriazole. The passive layer is insoluble in aqueous and many organic solutions. There is a positive correlation between the thickness of the passive layer and the efficiency of preventing corrosion. BTA is used in conservation, notably for the treatment of bronze disease. The exact structure of the copper-BTA complex is controversial and many proposals have been suggested. Source: Wikipedia