Metal-Organic Frameworks (MOFs) as Safer, Structurally Reinforced Energetics

• Published in: Chemistry : a European journal 2013-01, Vol.19 (5), p.1706-1711
• Main Authors: Bushuyev, Oleksandr S., Peterson, Geneva R., Brown, Preston, Maiti, Amitesh, Gee, Richard H., Weeks, Brandon L., Hope-Weeks, Louisa J.
• Format: Article
• Language: English
• Subjects: Anions; Architecture; Chemistry; coordination polymers; crystal engineering; Crystal structure; density functional calculations; Detonation; Energetic materials; Lead (metal); Ligands; Metal-organic frameworks; Reinforcement; Zinc coordination
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201203610

Second‐generation cobalt and zinc coordination architectures were obtained through efforts to stabilize extremely sensitive and energetic transition‐metal hydrazine perchlorate ionic polymers. Partial ligand substitution by the tridentate hydrazinecarboxylate anion afforded polymeric 2D‐sheet structures never before observed for energetic materials. Carefully balanced reaction conditions allowed the retention of the noncoordinating perchlorate anion in the presence of a strongly chelating hydrazinecarboxylate ligand. High‐quality X‐ray single‐crystal structure determination revealed that the metal coordination preferences lead to different structural motifs and energetic properties, despite the nearly isoformulaic nature of the two compounds. Energetic tests indicate highly decreased sensitivity and DFT calculations suggest a high explosive performance for these remarkable structures. More than the sum of the parts: Crystal engineering efforts have generated energetic 2D MOFs to replace conventional heavy‐metal‐based primers. The building blocks were selected for their structural characteristics and energetic contribution. The long‐range structural reinforcement in these layered, multidimensional structures affords desirably attenuated sensitivity to detonation (see figure).