Cerium-promoted conversion of dinitrogen into high-energy-density material CeN<sub>6</sub> under moderate pressure

Wang Yuanyuan; Li Zhihui; Niu Shifeng; Yi Wencai; Liu Shuang; Yao Zhen; Liu Bingbing

doi:10.1063/5.0136443

Volume 8 Issue 3

May 2023

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Wang Yuanyuan, Li Zhihui, Niu Shifeng, Yi Wencai, Liu Shuang, Yao Zhen, Liu Bingbing. Cerium-promoted conversion of dinitrogen into high-energy-density material CeN6 under moderate pressure[J]. Matter and Radiation at Extremes, 2023, 8(3): 038401. doi: 10.1063/5.0136443

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Wang Yuanyuan, Li Zhihui, Niu Shifeng, Yi Wencai, Liu Shuang, Yao Zhen, Liu Bingbing. Cerium-promoted conversion of dinitrogen into high-energy-density material CeN₆ under moderate pressure[J]. Matter and Radiation at Extremes, 2023, 8(3): 038401. doi: 10.1063/5.0136443

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Cerium-promoted conversion of dinitrogen into high-energy-density material CeN₆ under moderate pressure

doi: 10.1063/5.0136443

Wang Yuanyuan^1
,,
Li Zhihui¹,
Niu Shifeng^2
,,
Yi Wencai^{3
,
,},
Liu Shuang^{1
,
,},
Yao Zhen^{1
,
,
,},
Liu Bingbing^{1
,
,}

1.
State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People’s Republic of China
2.
Henan Key Laboratory of Photoelectric Energy Storage Materials and Applications, School of Physics and Engineering, Henan University of Science and Technology, Luoyang 471023, People’s Republic of China
3.
Laboratory of High Pressure Physics and Material Science (HPPMS), School of Physics and Physical Engineering, Qufu Normal University, Qufu, Shandong 273165, People’s Republic of China

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Corresponding author: a)Authors to whom correspondence should be addressed: yiwc@qfnu.edu.cn, liu_shuang@jlu.edu.cn, yaozhen@jlu.edu.cn, and liubb@jlu.edu.cn
Received Date: 2022-11-26
Accepted Date: 2023-03-16

Available Online: 2023-05-01

Publish Date: 2023-05-01

Abstract

Abstract

Synthesis pressure and structural stability are two crucial factors for highly energetic materials, and recent investigations have indicated that cerium is an efficient catalyst for N₂ reduction reactions. Here, we systematically explore Ce–N compounds through first-principles calculations, demonstrating that the cerium atom can weaken the strength of the N≡N bond and that a rich variety of cerium polynitrides can be formed under moderate pressure. Significantly, P1̄-CeN₆ possesses the lowest synthesis pressure of 32 GPa among layered metal polynitrides owing to the strong ligand effect of cerium. The layered structure of P1̄-CeN₆ proposed here consists of novel N₁₄ ring. To clarify the formation mechanism of P1̄-CeN₆, the reaction path Ce + 3N₂ → trans-CeN₆ → P1̄-CeN₆ is proposed. In addition, P1̄-CeN₆ possesses high hardness (20.73 GPa) and can be quenched to ambient conditions. Charge transfer between cerium atoms and N₁₄ rings plays a crucial role in structural stability. Furthermore, the volumetric energy density (11.20 kJ/cm³) of P1̄-CeN₆ is much larger than that of TNT (7.05 kJ/cm³), and its detonation pressure (128.95 GPa) and detonation velocity (13.60 km/s) are respectively about seven times and twice those of TNT, and it is therefore a promising high-energy-density material.

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