This is promising. stimulating hydrogen or oxygen production directly from water was far too costly in terms of energy. Now we have a subtle way to bring it about.
Microwave Water Splitting for Breakthroughs for Making Hydrogen, Oxygen and Fast Battery Charging
Brian Wang | November 5, 2020
Researchers from the Polytechnic University of Valencia and the Spanish National Research Council (CSIC) report contactless H2 production via water electrolysis mediated by the microwave-triggered redox activation of solid-state ionic materials at low temperatures (less than 250 °C).
This will simplify and significantly cheapen the process for hydrogen production.
Water was reduced via reaction with non-equilibrium gadolinium-doped CeO2 that was previously in situ electrochemically deoxygenated by the sole application of microwaves. The microwave-driven reduction was identified by an instantaneous electrical conductivity rise and O2 release. This process was cyclable, whereas H2 yield and energy efficiency were material- and power-dependent. Deoxygenation of low-energy molecules (H2O or CO2) led to the formation of energy carriers and enabled CH4 production when integrated with a Sabatier reactor. This method could be extended to other reactions such as intensified hydrocarbons synthesis or oxidation.
Ultra-fast Charging of Batteries and Space Exploration Applications
The technology could also be applied for ultra-fast charging of batteries. It could enable a practically instantaneous decrease in the size of the electrode (metallic anode) that stores energy. We would go from a layer-based progressive charging process, which can take hours, to a simultaneous process in the entire electrolyte, which would make it possible to charge a battery in a few seconds,” says José Manuel Catalá.
Another use would be the direct generation of oxygen with microwaves, which opens a broad spectrum of new uses. This could enable direct production of oxygen with extra-terrestrial rocks which would be huge for enabling the colonization of the Moon, Mars or other rock bodies of the solar system.
A Short History of the Discovery
Ionic materials that were treated with microwaves showed unusual changes in their properties, especially their electronic conductivity. This did not happen when they were heated conventionally.
Microwaves interact with these materials by accelerating the electrons and giving way to the release of molecules of oxygen from their structure (which is also called reduction). This change manifested itself specifically with sudden alterations to the conductivity at relatively low temperatures (approximately 300ºC).