Nitrogen Dissociation via Reaction with Lithium Alloys
Nitrogen Dissociation via Reaction with Lithium Alloys
复制标题
通过与锂合金反应解离氮
DOI：
10.1021/acsomega.6b00498
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发表时间：
2017
期刊：
影响因子：
4.1
通讯作者：
and Hiroki Miyaoka
中科院分区：
文献类型：
--
作者：
Shotaro Yamaguchi;Takayuki Ichikawa;Yongming Wang;Yuki Nakagawa;Shigehito Isobe;Yoshitsugu Kojima;and Hiroki Miyaoka
锂合金是由金属锂与碳、硅、锗、锡等14族元素反应合成的。通过热分析和结构分析研究了其加氮和脱氮性能。在低于500℃的温度下，所有合金都能解离气态分子的氮三键，形成原子态的氮化物，这比传统的热化学和催化合成氮化物所需的温度要低。除锗外，其余合金的产物均为纳米级氮化锂。氮化锂与金属的脱氮（脱氮）反应是与氮化反应理想的相反反应，通过加热至600℃形成锂合金。其中，锂-锡合金是一种有潜力的材料，在500℃以下通过可逆反应控制氮的解离和复合，合金相中可用锂量最大。锂合金在较低温度下的氮化和脱氮反应是利用锂与氮的高反应活性和锂的迁移率来实现的。上述基于锂合金的反应适用于氨的合成。因此，在0.5 MPa的压力下，在500℃以下可以合成氨。因此，使用锂合金的反应被认为是氨合成的伪催化剂。
Lithium alloys are synthesized by reactions between lithium metal and group 14 elements, such as carbon, silicon, germanium, and tin. The nitrogenation and denitrogenation properties are investigated by thermal and structural analyses. All alloys dissociate the nitrogen triple bond of gaseous molecules to form atomic state as nitrides below 500 °C, which is lower than those required for conventional thermochemical and catalytic processes on nitride syntheses. For all alloys except for germanium, it is indicated that nanosized lithium nitride is formed as the product. The denitrogenation (nitrogen desorption) reaction by lithium nitride and metals, which is an ideal opposite reaction of nitrogenation, occurs by heating up to 600 °C to form lithium alloys. Among them, the lithium–tin alloy is a potential material to control the dissociation and recombination of nitrogen below 500 °C by the reversible reaction with the largest amount of utilizable lithium in the alloy phase. The nitrogenation and denitrogenation reactions of the lithium alloys at lower temperature are realized by the high reactivity with nitrogen and mobility of lithium. The above reactions based on lithium alloys are adapted to the ammonia synthesis. As a result, ammonia can be synthesized below 500 °C under 0.5 MPa of pressure. Therefore, the reaction using lithium alloys is recognized as a pseudocatalyst for the ammonia synthesis.