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arXiv · 2403.05951

Free-standing cubic gauche nitrogen stable at 760 K under ambient pressure

Yuxuan Xu·Guo Chen·Fei Du·Ming Li·Liangfei Wu·Deyuan Yao·Junfeng Ding·Zhi Zeng·Haiqing Lin·Xianlong Wang
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Abstract

Cubic gauche nitrogen (cg-N) has received wide attention due to its high energy density and environmental friendliness. However, existing synthesis methods for cg-N predominantly rely on the high-pressure techniques, or the utilization of nanoconfined effects using highly toxic and sensitive sodium azide as precursor, which significantly restrict the practical application of cg-N as high energy density materials (HDEM). Here, based on the first-principles simulations, we find that the adsorption of potassium on the cg-N surface exhibits superior stabilization compared to sodium. Then, we chose the safer potassium azide as raw material for synthesizing cg-N. Through plasma-enhanced chemical vapor deposition treatment, the free-standing cg-N was successfully synthesized without the need of high-pressure and nanoconfined effects. Importantly, it demonstrates excellent thermal stability up to 760 K, and then a rapid and intense thermal decomposition occurs, exhibiting typical behaviors of HDEM thermal decomposition. Our work has significantly promoted the practical application of cg-N as HDEM.

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Yuxuan Xu, Guo Chen, Fei Du, Ming Li, Liangfei Wu, Deyuan Yao, Junfeng Ding, Zhi Zeng, Haiqing Lin, Xianlong Wang. 2024-03-09. Free-standing cubic gauche nitrogen stable at 760 K under ambient pressure. https://arxiv.org/abs/2403.05951

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