Fine-tuned ru catalyst microenvironment increases hydrogen oxidation under alkaline conditions

A team of researchers at the HEFEI Institutes of Physical Science at the Chinese Academy of Sciences has announced a new strategy to enhance the performance of ruthenium (RU) catalysts. This study was recently published in Nano Letters.

Ru has emerged as a promising alternative, but under alkaline conditions its catalytic activity is hampered by the strong adsorption of hydrogen (H*) and hydroxyl (OH*) intermediates, slowing the reaction.

In this study, researchers led by Professor Wang Hun collaborated with Professor Zheng Fangcai and Professor Luo Qiquan of Anhui University to promote a strategy to fine-tune Ru’s local electronic environment. By embedding RU atoms within the manganese oxide lattice, we designed an interface Ru–O bond confirmed through electron spin resonance (ESR) spectroscopy in a steady-state high-field experimental facility.

This interface engineering induces a downward shift in the D-band center of the ru atom, optimizing the adsorption behavior of the reaction intermediates and lowering the energy barrier to water formation. The results showed a significant mass activity of 1.26 mA per microgram of RU at 0.1 m KOH. This is 13 times larger than the benchmark RU/C catalyst, eight times more than the commercially available PT/C. The catalyst also exhibited excellent durability and strong resistance to carbon monoxide poisoning.

This study presents a new strategy for improving Hor catalysts by regulating interface electronic structures. Not only will it set up new benchmarks for RU-based materials, it will also provide a deeper understanding of how magnetic field technologies such as ESR can play a role in advanced catalyst design.