Dinitrogen Activation Using Heterobimetallic Complexes Supported by an Extended Cryptand Ligand

化肥。洗涤剂。尼龙。所有这些产品都是从氨中提取的，每年由哈伯-博世工艺以百万吨的规模生产氨。这是世界上最重要的工业过程之一：它是将大气中的氮转化为氨的唯一商业上可行的方法。然而，哈伯-博世进程对环境的影响是巨大的：全球能源需求的1%-2%和全球二氧化碳排放量的1.4%是该进程的直接结果。尽管经过了一个多世纪的研究，但还没有开发出商业上可行的替代方案来减轻这种损害。Haber-Bosch工艺消耗如此多能源的原因之一是需要打破两个氮原子之间非常强的三重键，然后与氢气反应生成氨。该项目旨在开发一种全新的合成氨方法，通过使用单个分子作为催化剂，在一步内打破三键形成氨。单分子的关键特征是它将包含两个不同的过渡金属原子。一种金属将负责结合和激活氮，而另一种金属原子将进行氢化形成氨。使用两个不同的金属原子意味着每种金属都可以是其所需工作的最佳金属原子，而更传统的基于金属的催化剂必须在该反应的一个(或两个)部分做出妥协。通过选择最适合这项工作的金属，反应的能量需求将大大减少。这将转化为全球范围内更低的二氧化碳排放和更低的能源消耗。

Fertilisers. Detergents. Nylons. All of these products are derived from ammonia, which is produced on a megaton scale every year by the Haber-Bosch process. This is one of the world's most important industrial processes: it is the only commercially viable method for transforming nitrogen from the atmosphere into ammonia. However, the environmental impact of the Haber-Bosch process is huge: between 1-2% of the global energy demand, and 1.4% of global CO2 emissions, are a direct result of this process. Despite over a century of research, no commercially viable alternatives have been developed to mitigate this damage.One of the reasons that the Haber-Bosch process consumes so much energy is the need to break the very strong triple bond between two nitrogen atoms, followed by the reaction with hydrogen to generate ammonia. This project aims to develop an entirely new method for synthesising ammonia by using a single molecule as a catalyst to break that triple bond and form ammonia, all in one step. The key feature of the single molecule is that it will incorporate two different transition metal atoms. One metal will be responsible for binding and activating nitrogen, whilst the other metal atom will carry out the hydrogenation to form ammonia. Using two different metal atoms means that each metal can be the best one for the job it needs to do, whereas more traditional metal-based catalysts have to compromise on one (or both) parts of this reaction. By selecting the best metals for the job, the energy demand of the reaction will be substantially reduced. This will translate into lower CO2 emissions and lower energy consumption on a global scale.