H₂ and O₂ activation by [NiFe]hydrogenases – Insights from model complexes

H₂ is an important compound from both a biological and a chemical industry perspective. Oxidation and reduction enable H₂ to be used as a source of energy and as a raw material in the manufacture of a variety of useful substances. In nature, hydrogenases (H₂ases) have been entrusted with the task of activating H₂, making it responsible for part of the Earth's energy circulation system since the birth of the planet. H₂ases have distinctive active centers and their structures and electronic states can be controlled to produce specific functions. This paper provides an overview of the structures and functions of H₂ases and their models.