Microwaves Deliver Clean Hydrogen in Minutes
Microwaves Deliver Clean Hydrogen in Minutes
Microwave energy cuts hydrogen production costs and energy use.
TechnologyNetworks.com | January 22, 2025
An interdisciplinary team at POSTECH, led by Professor Gunsu S. Yun, doctoral candidate Jaemin Yoo (Department of Physics, Division of Advanced Nuclear Engineering), Professor Hyungyu Jin, and doctoral candidate Dongkyu Lee (Department of Mechanical Engineering), has developed a groundbreaking technology that addresses key limitations in clean hydrogen production using microwaves. They have also successfully elucidated the underlying mechanism of this innovative process. Their findings, published as the Inside Front Cover of Journal of Materials Chemistry A, mark a transformative step in the pursuit of sustainable energy.
As the world shifts away from fossil fuels, clean hydrogen has emerged as a leading candidate for next-generation energy due to its zero carbon emissions. However, existing hydrogen production technologies face significant barriers. Conventional thermochemical methods, which rely on the oxidation-reduction of metal oxides, require extremely high temperatures of up to 1,500°C. These methods are not only energy-intensive and costly but also challenging to scale, limiting their practical application.
To address these challenges, the POSTECH team turned to a familiar yet underutilized energy source: “microwaves”1 energy, the same source used in household microwave ovens. While microwaves are commonly associated with heating food, they can also drive chemical reactions efficiently. The researchers demonstrated that microwave energy could lower the reduction temperature of Gd-doped ceria (CeO2)—a benchmark material for hydrogen production—to below 600℃, cutting the temperature requirement by over 60 percent. Remarkably, microwave energy was found to replace 75 percent of the thermal energy needed for the reaction, a breakthrough for sustainable hydrogen production.
Another critical advancement lies in the creation of “oxygen vacancies”2, which are defects in the material structure essential for splitting water into hydrogen. Conventional methods often take hours at extremely high temperatures to form these vacancies. The POSTECH team achieved the same results in just minutes at temperatures below 600°C by leveraging microwave technology. This rapid process was further validated with a thermodynamic model, which provided valuable insight into the mechanism underlying the microwave-driven reaction...more
https://www.technologynetworks.com/tn/news/microwaves-deliver-clean-hydrogen-in-minutes-395265
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It's really not worth too much effort to try to address fossil fuel advertising in a three card Monte systems with something called science, but even a fool with no science education whatsoever can understand it takes energy to run a microwave.
The full original paper (as opposed to a journalistic representation subject to misinterpretation) is here: Dongkyu Lee, Jaemin Yoo, Gunsu S. Yun and Hyungyu Jin J. Mater. Chem. A, 2024,12, 33526-33536
Notably, one of the authors, Dr. Gunsu Yun, is from the Division of Advanced Nuclear Engineering, Pohang University of Science and Technology. Our fossil fuel salespeople trying to rebrand fossil fuels at hydrogen here and elsewhere, like most advocates of continued fossil fuel dependence run around expressing their hatred of nuclear energy, since unlike hydrogen, it is primary energy and thus capable of eliminating dependence on fossil fuels.
The paper represents an effort to reduce the required temperatures for the thermochemical production of hydrogen, presumably for captive use, using primary nuclear energy, thus lowering the enthalpy and entropy penalty of making hydrogen from water, although the penalty exists, as it must from the laws of thermodynamics.
The authors explicitly state the magnitude of the energy losses for the production of hydrogen in the process.
Since DU lacks an equation editor, I'll post the relevant text as a graphic object:
The energy required to produce a kg of H2 is given as between 65 kWh/kg and 80 kWh/kg, which translates into 234 MJ/kg and 284 MJ/kg.
A kg of H2 has a heating value (depending on the thermodynamics of the device in which it is consumed) of between 120-142 MJ/kg.
Thus at the high end, the energy lost in this scheme to waste energy to make hydrogen - the purpose of which is uniformly to greenwash fossil fuels - is 140 MJ/kg and at the low end, 117 MJ/kg.
The laws of thermodynamics are not subject to being overturned by marketing. They are inviolable laws of physics, as well the authors understand. They're scientists, not marketeers trying to greenwash fossil fuels.
What they have not explicitly discussed is that electricity is required to run a microwave, and electricity, by its very nature is a thermodynamically degraded form of energy.
The only value of this process would be a situation where excess electricity was produced in off peak hours as a result of process intensification to recover exergy from nuclear heat.
Otherwise, thermochemical cycles avoiding electricity will always be thermodynamically superior, since it is far more direct, but no matter how hydrogen is made, it destroys exergy, the recoverable energy of a process.
Have a nice evening.