Scientists call for caution over ‘green’ fertiliser breakthroughs
A new study led by Monash University chemists is urging caution around recent claims of "green" breakthroughs in fertiliser production, warning that some results may be overstated due to flaws in experimental design.
Published in the prestigious journal Joule, the study is led by Dr Mattia Belotti, Associate Professor Alexandr Simonov and Professor Doug MacFarlane from the School of Chemistry.
It critically reviews emerging research focused on developing direct nitrogen oxidation processes—a potential method for producing nitrate fertilisers using only nitrogen gas, water, and renewable energy.
The concept is highly attractive.
Current fertiliser production depends on the Haber-Bosch and Ostwald processes, which are energy-intensive, require high temperatures and pressures, and produce significant greenhouse gas emissions.
A more sustainable, electricity-driven process based on nitrogen oxidation* could help reduce emissions from one of the world’s most essential yet environmentally costly industries. “A clean, direct pathway to nitrate fertilisers would be a major step forward for sustainable agriculture,” said Associate Professor Simonov.
“But our review suggests that many of the published results in this field may not stand up to closer scrutiny.”
The researchers analysed a wide range of studies on electrochemical and photochemical nitrogen oxidation and identified common pitfalls—particularly the risk of contamination and false readings. In several cases, the detected nitrate may not have come from actual nitrogen conversion, but instead from impurities or background sources. “Many of these studies aren’t applying the rigorous checks needed to confidently confirm their results,” said Dr Belotti.
“Without strong experimental controls, it’s easy to be misled.”
While isotope labelling is the gold standard for verifying nitrogen conversion, the authors note that this method is costly and not always accessible.
To help improve the field, they propose a new framework of practical, lower-cost recommendations to help researchers avoid common errors and improve reproducibility.
“We want to support innovation by helping researchers get it right from the start,” said Associate Professor Simonov. “That means building robust, transparent methods that can reliably demonstrate progress.”
If successful, direct nitrogen oxidation could eventually provide a cleaner, low-carbon pathway to nitrate fertiliser production—potentially transforming a process that currently sustains over half the global population.
“But the path forward requires careful, well-designed science,” said Dr Belotti.
“We need to be realistic about where we are and what still needs to be done.”
*Note that nitrate can be produced using plasma-based approaches.
Further information
Silvia Dropulich
Marketing, Media & Communications Manager, Monash Science
T: +61 3 9902 4513 M: +61 435 138 743
Email: silvia.dropulich@monash.edu