Taming nitroformate through encapsulation with nitrogen-rich hydrogen-bonded organic frameworks

Area of Science:

• Energetic Materials Science
• Materials Chemistry
• Organic Frameworks

Background:

• Nitroformate (NF) compounds are attractive oxidants for propellants and explosives due to simple preparation and high oxygen content.
• Poor thermal stability of NF derivatives has historically limited their practical applications for over 150 years.

Purpose of the Study:

• To design and construct a novel nitrogen-rich hydrogen-bonded organic framework (HOF-NF) for stabilizing nitroformate anions.
• To overcome the thermal stability limitations of NF-based energetic materials.

Main Methods:

• Self-assembly of a nitrogen-rich hydrogen-bonded organic framework (HOF).
• Incorporation of nitroformate (NF) anions into the HOF pores via ionic and hydrogen bonding interactions.
• Thermal stability analysis of the resulting HOF-NF moiety.

Main Results:

• The first example of a nitrogen-rich HOF-NF was successfully designed and constructed.
• The HOF-NF moiety exhibited a decomposition temperature of 200°C, surpassing the critical 180°C threshold for thermal stability.
• NF anions were effectively stabilized within the HOF framework through dual ionic and hydrogen bonding forces.

Conclusions:

• The developed HOF-NF strategy successfully addresses the critical thermal stability challenge for NF-based compounds.
• This work provides a new platform for designing and synthesizing a wide range of stable, high-performance NF-based energetic materials.