Lanthanide Complexes of Bis(tetrazolato)amine: A Route to Lanthanide Nitride Foams

Metal nitrides are strong refractory ceramic materials known for applications in the coatings, catalysis, and semiconductor industries. Lanthanide nitrides are difficult to prepare in high purity and often require high temperatures and sophisticated equipment. In this work, we present an approach to the synthesis of high-purity f-element nitrides through the use of simple lanthanide salts and the nitrogen-rich ligand 5,5'-bis(1H-tetrazolyl)amine (H₂BTA) to form lanthanide complexes of 5,5'-bis(tetrazolato)amine (BTA^2-). We have demonstrated that, when dehydrated, these types of complexes undergo a self-sustained combustion reaction under an inert atmosphere to yield nanostructured f-element nitride foams for lanthanum and cerium. The synthesis, characterization, and single-crystal X-ray crystallography of the BTA^2- complexes of lanthanum, cerium, praseodymium, neodymium, and europium are also discussed.