Researchers at the National University of Singapore (NUS) have developed a catalyst-regeneration strategy that could make hydrogen production from ammonia more efficient and reliable. By tackling a major problem that causes catalysts to lose their effectiveness over time, the team sustained hydrogen production for over 2,000 hours in laboratory tests.
Ammonia is a promising way to store and transport hydrogen, a clean energy source that produces no carbon dioxide when used in fuel cells. Electrochemical ammonia cracking uses electricity to convert ammonia into nitrogen and hydrogen, offering a potentially energy-efficient way to produce hydrogen close to where it is needed. However, the platinum (Pt)-based catalysts used in this process gradually become less effective as their surfaces undergo oxidation and become blocked by nitrogen. This limits their operating efficiency and durability.
Keeping catalysts active for longer
A research team led by Professor CHEN Wei from the NUS Department of Physics and the Department of Chemistry developed a catalyst comprising platinum nanoparticles supported on nitrogen-doped carbon containing atomically dispersed iron sites. Known as Pt/Fe-NC, the catalyst resists both platinum oxidation and nitrogen poisoning during ammonia oxidation.
First, electron transfer from the Fe-NC support suppresses platinum oxidation and accelerates the rate-determining dehydrogenation step. Second, Fe-N 4 sites promote water dissociation, facilitating the hydrogenation of poisoning nitrogen species on platinum to form reactive NH-containing intermediates. This helps free up blocked sites and restore the catalyst's activity.
The research work was carried out in collaboration with Assistant Professor OU Pengfei from the NUS Department of Chemistry and Professor FAN Lei from the University of Electronic Science and Technology of China.
The research findings were reported in the scientific journal Nature Synthesis on 27 October 2026.
The new catalyst demonstrated more than 10 times the ammonia oxidation activity of a commercially available platinum-on-carbon catalyst under the tested conditions. It was also highly effective at producing hydrogen, allowing the same catalyst to be used for both key reactions in the process.
Sustaining hydrogen production for more than 2,000 hours
To extend the catalyst's operating life, the researchers combined periodic reversal of the electrical current with occasional acid washing and ammonia replenishment. This approach helps restore the catalyst's activity and maintain hydrogen production over extended periods.
Using this strategy, the team sustained hydrogen production for over 2,000 hours at a low electrical current and for 500 hours at a substantially higher current, demonstrating the potential for durable hydrogen production. Both tests were conducted at 80°C.
Towards more practical hydrogen production
By improving catalyst durability, this research brings ammonia-based hydrogen production a step closer to practical applications. As ammonia is easier to store and transport than hydrogen gas, the technology could support decentralised hydrogen production, reducing the challenges associated with hydrogen storage and transportation.
Dr JIANG Rui, a Research Fellow from the NUS Department of Chemistry on the team, said, “Our water-assisted regeneration approach helps prevent nitrogen from blocking the platinum surface, allowing the catalyst to remain active for longer. This is an important step towards achieving more reliable and sustained hydrogen production from ammonia.”
“These design principles may extend to other ammonia oxidation applications, including direct ammonia fuel cells,” added Professor CHEN.
While further research is needed to evaluate the technology at larger scales, the study provides a promising approach to improving the durability of catalysts used in hydrogen production.
Nature Synthesis
Experimental study
Not applicable
Catalyst regeneration enables durable electrochemical ammonia cracking for H2 production
27-Oct-2026