Green Hydrogen Production

For the first time in history, governments worldwide are coordinating their efforts to reach a decarbonized economy to curb the effects of climate change. Although renewables contribute to CO2 reductions, they are far from cost parity with fossil fuels, and their strong dependence on meteorological variations has motivated the search for new requirements to manage this intermittency. Hydrogen has emerged as an energy vector for other energy sectors because of its flexibility and wider range of applications across industry, transport, residential and commercial sectors. However, the potential use of hydrogen will require a global energy revolution that, nowadays has stifled progress.

Hydrogen production from electrolysis is the only technology able to produce pure green hydrogen in one step in a quick and controlled fashion without any carbon emissions[1]. However, there are still some drawbacks that need to be addressed:

The production cost gap compared with natural gas reforming could be saved using electricity from renewable power sources, although the main issue remains the high energy demand to electrochemically cleave the water molecule. In other words, water electrolysis technology is still unfriendly from an energy and economic point of view.

In light of this, the electrolysis of organic molecules offers several benefits, particularly in the context of sustainable chemistry and energy production. The organic molecules, susceptible to being electrolyzed, can be renewable feedstocks, such as biomass-derived compounds or waste materials, reducing the thermodynamic energy barrier of 1.23 V needed for the Oxygen Evolution Reaction (OER) in water electrolysis to a few 0.2 V. Furthermore, through electrolysis one can have more precise control over reaction conditions, enabling the selective conversion of organic molecules into valuable byproducts.

[1] Ayers, K., Danilovic, N., Ouimet, R., Carmo, M., Pivovar, B., Bornstein, M. (2019). Perspectives on Low-Temperature Electrolysis and Potential for Renewable Hydrogen at Scale. Annual Review of Chemical and Biomolecular Engineering 10, 219-239.