The development of secure, clean and efficient energy represents a fundamental societal challenge for Europe. Enormous technological challenges are awaiting not just in relation to the substitution of carbon-based fuels and systems but also to a rational utilization of the power generated by renewable sources (e.g. sun, wind), which are abundant but intermittent in nature, therefore requiring the development of an efficient energy storage back-up system. In such a scenario, power-to-gas technology, which relies on the production of a synthetic fuel by using electric power, is a very powerful approach as it is able to fulfill a number of functions. They include electrical energy storage in the form of hydrogen or its derivatives, production of carbon-free fuel for industry and mobility, transportation of energy via a gas distribution grid and supply of stand-alone systems.
In the power-to-gas process, water electrolysis, by which electricity is used to split water into molecular hydrogen and oxygen, plays a central role. Since the commercially available alkaline water electrolysis cells (which are based on anion exchange membranes) are insufficient for responding to the future demands in power-to-gas-systems owing to their low current density, the low purity of the produced H2 and the low dynamics, alternative technologies have recently come to the fore. Among these, Proton Exchange Membranes Electrolysis Cells (PEMECs), whose core is a solid polymer electrolyte, exhibit a number of highly competitive technological advantages. Owing to the high power density, the high gas purity, the rapid system response, the large dynamic range of operation and the compact design, PEMECs are ideal for operating in synergy with intermittent and variable power sources such as renewables.
PEMEC systems are a novel technology which will greatly benefit from innovation deriving from R&D activities. The project Thin-CATALYzER (thin-film based CATalyst LaYer for oxygen Evolution Reaction) promotes the practical implementation of PEMECs by developing a novel thin-film based platform for fundamental investigations and for the fabrication of a technologically relevant catalyst layer, which serves both to gain new understanding on the fundamental mechanisms of water electrolysis and for tackling some of the main current limitations of state-of-the-art PEMEC systems.
