Researchers from the University of Adelaide have made significant progress in improving the efficiency of iridium-based catalysts for renewable energy. 

The breakthrough could bring the world closer to the widespread use of intermittent renewable energy sources. 

The team, led by Associate Professor Yao Zheng, has developed a lattice-water-assisted mechanism that enhances the performance of iridium oxide catalysts used in proton exchange membrane water electrolysis (PEMWE).

“Currently, it is difficult for commercial iridium oxide catalysts to achieve high activity and stability simultaneously in PEMWE. Our research shows that arranging water molecules in a specific pattern can enhance the efficiency of the catalyst by 5 to 12 per cent, resulting in higher energy output while consuming less energy,” Professor Yao Zheng says. 

PEMWE is a promising method for generating green hydrogen, which has been hailed as the low-emission fuel of the future. 

Iridium-based electrocatalysts are crucial in this process due to their ability to withstand the harsh acidic conditions during the water-splitting reaction.

Given that iridium is one of the rarest elements on Earth, Associate Professor Zheng says the world needs ways to reduce its usage in catalysts. 

The lattice-water-assisted oxygen exchange mechanism proposed by the team allows for the reduction of iridium content, thereby decreasing the cost of green hydrogen production.

“This discovery not only confirms the feasibility of using low-loading iridium-based anodic catalysts for PEMWE but also offers new insights into high-performance oxygen evolution reaction (OER) catalyst design,” adds Professor Zheng. 

Cheaper green hydrogen production would accelerate the transition to a carbon-neutral society and effectively address climate-related challenges.

While the team's findings, published in Science Advances, represent a significant advancement at the fundamental level, further research is necessary to scale up the new synthesis process. 

Nonetheless, this breakthrough paves the way for a future where renewable energy can be harnessed more efficiently, bringing the world closer to achieving sustainable energy goals.

The findings are published in the journal Science Advances.