间接的,可逆的高密度储存在紧的金属氨胺盐中
Rasmus Z Sørensen1, Jens S Hummelshøj, Asbjørn Klerke
1Center for Sustainable and Green Chemistry, Department of Chemistry, Building 206, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Journal of the American Chemical Society
|June 14, 2008
概括
像Ca ((NH3) 8Cl2这样的金属氨基化物提供了高容量的间接存储. 这些材料迅速释放氨 (NH3) 和 (H2),显示出储存应用的潜力.
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.
- 储存技术 储存技术
背景情况:
- 开发高效的存材料对于推进清洁能源技术至关重要.
- 金属氨基化物是间接储存的有希望的途径,因为它们的含量很高.
研究的目的:
- 为了研究Mg (NH3) 6Cl2,Ca (NH3) 8Cl2,Mn (NH3) 6Cl2和Ni (NH3) 6Cl2) 的间接储潜力.
- 为了分析氨 (NH3) 和 (H2) 从这些金属氨化物中释放动力学和机制.
主要方法:
- 将金属氨基化物压缩成密集的固体片.
- 使用不同加热速率的温度调节溶解 (TPD) 来研究NH3的释放.
- 采用密度函数理论 (DFT) 计算来建模溶解和机制.
主要成果:
- 所有四种金属氨基化物在压缩时都达到高密度 (>95%的晶体密度).
- (NH3) 8Cl2显示出显著的储能 (高达9.78重 % H 和0.116公斤 H/L).
- NH3的脱吸主要受到热传递的限制,这表明其运动速度很快,而纳米孔状结构促进了Mg (NH3) 6Cl2,Mn (NH3) 6Cl2和Ni (NH3) 6Cl2) 的脱吸.
结论:
- 金属氨基化物是间接储存的有效材料,具有高的重力度和体积密度.
- 快速消化动力学归因于传热限制和纳米孔状结构的形成.
- DFT计算支持表面链释放机制,用于快速的吸收/脱吸周期.
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