Deriving High-Energy-Density Polymeric Nitrogen N10 from the Host-Guest ArN10 Compound.

Abstract

Discovering stable polymeric nitrogen phases and exploring their properties are crucial for energy storage and conversion, garnering significant attention. In this study, we investigate the formation possibility of a stable compound between Ar and N₂ through ab initio calculations under low-pressure conditions (0-100 GPa). The novel super nitride, Imm2 ArN_10, is designed to demonstrate robust thermodynamic stability under high pressures (91 GPa) and showcase the unique host-guest structure, in which guest atoms (Ar) are trapped inside the host polymeric N₁₀. Significantly, given the weak interaction between Ar and N atoms and a channel parallel to the c-crystallographic axis in ArN₁₀, we propose a novel method to stabilize the previously unknown polymeric nitrogen structure, Imm2-N₁₀, by removing the guest argon atoms from the natural channels of ArN₁₀. Imm2 ArN₁₀ and N₁₀ are thermodynamically and dynamically stable, with energy densities of 9.1 kJ g^-1 and 12.3 kJ g^-1, respectively-more than twice that of TNT. Additionally, ArN₁₀ and N₁₀ stand out as leading green energetic materials, boasting a superior explosion velocity of 17.56 km s^-1 and a detonation pressure of 1712 kbar, surpassing that of TNT. These findings significantly impact on the creation of pure nitrogen frameworks through chemical reactions involving inert elements under high pressure.