Electrocatalytic energy conversion

Electrocatalytic energy conversion has attracted extensive attention owing to its multiple benefits such as high efficiency, good reaction selectivity combined with environmentally benign morality. Among a large variety of the electrocatalytic pathways, the electrocatalytic oxygen evolution reaction (OER)for water electrolysis and electrooxidation of energy-containing small molecules like urea are highly attractive. On the one hand, OER is not only considered as an important process of water overall cracking and co catalysis in photoelectrochemical reaction, but also considered as a half reaction with limited speed in water electrolysis due to the lag of its four electron reaction mechanism; on the other hand, urea, as a common waste in polluted water, has been paid more and more attention in the application of water electrolysis. It has been considered to be a promising chemical for hydrogen production in electrolytic cell. Unfortunately, the study of urea oxidation reaction (UOR) is still in its infancy due to the harsh reaction mechanism which involves 6-electron transfer process. At present, the types of double functions of OER ＆ UOR catalysts are mainly concentrated on Ni(OH)2 nanomaterials, Ni-based oxides, and very few MOFs and their derivative material, because the above materials have common features such as, a large amount of active sites, good electrical conductivity, and robust structure. At the same time, the unique UOR activity of Ni-based catalysts and the catalytic environment of strong alkaline conditions also limit the development and expansion of other material systems, especially for coordination clusters that are generally unstable in basic conditions. So far, there are no reports about coordination molecular clusters applied to OER and UOR reactions. Therefore, designing and developing coordination molecular cluster-based double functions of OER and UOR catalysts with strong stability and good reactivity to enrich the material systems is a new major challenge.