反应机制研究LiNH2BH3和 (LiH) n (n = 1-5) 基于密度函数理论的集群
Xiao Dong1, Rong Yuan1, Genzhuang Li1
1Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters, College of Physical Science and Technology, Yili Normal University, Yining 835000, China.
Molecules (Basel, Switzerland)
|February 26, 2025
概括
胺多 (LiNH2BH3) 可以储存气,但在高温下会释放它. 添加化 ((LiH) n) 集群降低了释放温度,提高了储存效率.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 计算化学的计算化学
背景情况:
- 能是一种有前途的清洁能源,但安全高效的储存仍然是一个挑战.
- 胺多 (LiNH2BH3) 是一种潜在的储物材料,但其释放的温度很高.
- 众所周知,化 (LiH) n集群会影响金属-N-H系统.
研究的目的:
- 使用理论计算,研究LiNH2BH3与 (LiH) n集群 (n=1-5) 的反应机制.
- 分析 (LiH) n集群对LiNH2BH3.3释放的特性的影响.
- 为了确定最佳配置以提高储能性能.
主要方法:
- 用密度函数理论 (DFT) 的计算来研究反应机制.
- 对LiNH2BH3 (LiAB),LiNH2BH3-LiH (Li2AB) 和LiNH2-LiH (Li2A) 系统的边界轨道进行分析.
- 在不同地点计算和比较原子解离能.
主要成果:
- LiNH2BH3与 (LiH) n集群的脱是通过Hδ-(Li) ···Hδ+(N) 相互作用促进的,最小能量屏障为113.34kJ/mol.
- -BH3和-LiH组的存在在LiNH2BH3-LiH系统中显著影响释放性能.
- 在LiAB,Li2AB和Li2A中,原子解离能量的顺序是 ΔE(H(N)) > ΔE(H(B)) > ΔE(H(Li)) .
结论:
- 与单独的LiNH2BH3 (LiAB) 和LiNH2-LiH (Li2A) 相比,LiNH2BH3-LiH系统显示了增强的脱性能.
- 添加LiH集群有效降低释放温度,改善LiNH2BH3.3的储能能力.
- 理论计算为优化未来清洁能源应用的存材料提供了宝贵的见解.
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