Iron-only hydrogenases: a functional artificial H-cluster

在电极上将质子转化为氢，并反过来从氢中获取电能，这是对氢经济至关重要的反应。铂目前是最好的催化剂，既可以通过电解从水中获得氢作为燃料，也可以通过在燃料电池中氧化氢气来利用氢气发电。它是一种昂贵的金属，从长远来看，从不断扩大的氢经济的需求来看，它可能是不可持续的。还提出了与供应安全有关的问题。大自然使用氢酶来催化细菌和藻类中氢的产生或使用，从而进行同样的反应。其中一种酶的核心是一簇铁和硫原子(丰富的元素)，被称为H-原子簇。我们正在解决的问题是，我们能否根据大自然的蓝图制造新材料，以取代燃料电池中的铂？到目前为止，我们和其他人已经证明，可以合成与酶的催化中心非常相似的结构。然而，事实证明，这些催化剂质量很差，部分原因是人造结构中的一个铁原子上附着着一个额外的一氧化碳分子，这就阻碍了它与氢或质子的反应。这个项目着手建立一个功能正常的H星系团。这将有助于我们加深对生物催化如何工作的理解，并可能提供具有技术意义的先导材料。

Converting protons to hydrogen at an electrode and its reverse getting electricity from hydrogen are reactions of fundamental importance to a hydrogen economy. Platinum is currently the best catalyst for both obtaining hydrogen as a fuel from water by electrolysis and using hydrogen to produce electricity by oxidising it in fuel cells. It is an expensive metal and in the long term is likely unsustainable with respect to demand from an expanding hydrogen economy . Issues relating to security of supply have also been raised. Nature carries out the same reactions using hydrogenase enzymes to catalyse the production or use of hydrogen in bacteria and algae . The machinery at the heart of one of these enzymes is a cluster of iron and sulfur atoms (abundant elements) known as the H-cluster. We are addressing the question 'can we make new materials based on nature's blueprint to replace platinum in fuel cells?' So far we and others have shown that structures closely similar to the catalytic centre of the enzyme can be synthesised. However these have proved poor catalysts, in part because the artifical structures have an 'extra' molecule of carbon monoxide attached to one of the iron atom and this 'blocks' its reaction with hydrogen or protons. This project sets out to build a functioning H-cluster. This will both help us to develop our understanding of how the biological catalysis works and may provide lead materials of technological relevance.