Green hydrogen? TCD study opts for gold, silver and copper

9 Sep 2021

Image: © RHJ/

Researchers at TCD are looking at using gold, silver and copper as a way of storing hydrogen energy in a more stable form.

As the climate crisis continues to worsen, scientists around the world are trying to figure out how to best transition to green energy. Some are betting on fusion power while others are trying to make strides with hydrogen energy. Not everyone is convinced that hydrogen is a straight-forward solution, however.

One particular problem with hydrogen energy is how to store it. At room temperature, hydrogen is volatile and reactive.

Storing it for use on board vehicles, for example, requires compression at very high pressures or cryogenic storage, both of which end up being very heavy and costing a lot of energy.

Solving this problem was the topic of a research study published in Chemistry Europe by a team of scientists from Trinity College Dublin (TCD).

“Among the greatest challenges facing humanity is the growing need to stop global warming and find more efficient and cleaner ways to produce energy,” said Cristina Trujillo, a research fellow in TCD’s School of Chemistry and the senior author of the article.

“As everybody already knows, the current production system and excessive use of fossil fuels is releasing much more CO2 into the atmosphere than is being absorbed naturally, which makes the creation of greener and more environmentally friendly alternatives a global priority.

“For decades now many research groups across the world have put their efforts into this issue. One of the most studied alternatives has been hydrogen as a clean and CO2-free energy source, but it presents multiple problems due to its reactivity, and low density and stability.”

Trujillo and colleagues focused on metal hydrides, an avenue of research that uses certain metal compounds to store hydrogen in a stable and compact form. Copper, gold and silver were all of particular interest to the team.

By partnering with scientists from the Institute of Medicinal Chemistry in Spain and the Irish Centre for High-End Computing, Trujillo and PhD candidate Inigo Iribarren were able to model gold, silver and copper hydrides using sophisticated computer techniques.

This is how they came to demonstrate that these metal hydrides could help bring about a more sustainable future as promising candidates for hydrogen storage.

“Our contribution here – made via quantum chemistry techniques – has been to show that gold, silver and copper hydride complexes are very likely to effectively retain hydrogen in a stable manner. We hope that this work will have multiple applications in time to come,” said Trujillo.

Sam Cox was a journalist at Silicon Republic covering sci-tech news