Researchers at Penn State University have uncovered an explanation for hydrogen spillover, a process that may be used in the production of clean fuels and hydrogen storage.
Hydrogen spillover was first defined in 1964, and it has regained attention as a potential pathway for harnessing hydrogen for use as clean energy. The phenomenon occurs when hydrogen atoms spill from a metal to an oxide during a catalytic reaction. Until the Penn State finding, however, no one has been able to quantify it or describe the underlying mechanism of the process. Researchers at Penn State found the key to hydrogen spillover to be thermal energy or entropy.
“We’ve known about spillover for a long time, but no one had found the right system to quantify and understand it,” said Bert Chandler, professor of chemical engineering and chemistry at Penn State. “We collected the data and figured out how to explain the phenomenon. It turns out, the balance of energies that we use is not always obvious, and entropy can drive things we don’t expect.”
Conventional hydrogen storage currently requires significant amounts of energy to keep hydrogen cool enough to remain in liquid form. The system used in the study specifically uses gold and titanium oxide for the catalytic reaction. Since gold requires very little thermal energy for a reaction to be initiated with hydrogen, it allows hydrogen molecules to be broken into hydrogen atoms at a much lower temperature. In the future, such converted atoms may be used as hydrogen fuel and storage.
Finding Could Support Currently Expanding Clean Hydrogen Market
Low-carbon hydrogen and green hydrogen have gained traction as viable renewable energy sources that may be used in a wide range of applications, from powering vehicles to clean energy storage, and they even present a potential avenue for eventually decarbonizing aviation. Addressing one of the main challenges to adopting hydrogen at an even larger scale, temperature and pressure requirements, could allow hydrogen energy to become more affordable and energy efficient. The present study has achieved the first step in addressing this obstacle.
The clean hydrogen market is expected to surpass the value of the liquid natural gas trade by 2030 and is also projected to grow to about $1.4 trillion per year by 2050. Penn State’s new findings have the potential to contribute to and even increase this growth expectation in the years to come.
