New catalyst boosts ammonia synthesis at ambient conditions

Researchers in China, Italy and Ireland say they have found a new way to make ammonia from nitrogen using a cobalt hydroxide catalyst, reaching record efficiency at room temperature and pressure. The work could point to a cleaner path for fertilizer production and other industrial uses that now depend on energy-intensive Haber-Bosch plants.

Why it matters: - Ammonia production underpins global agriculture, but the dominant Haber-Bosch process uses a lot of energy and produces major CO₂ emissions. - A working ambient-condition route could reduce reliance on centralized, carbon-heavy ammonia plants. - The same chemistry could also support ammonia’s growing role as a hydrogen carrier for energy storage and transport.

What happened: - Researchers from Qingdao Agricultural University, Politecnico di Milano and Trinity College Dublin developed a cobalt hydroxide catalyst for electrochemical nitrogen reduction. - The team reported a record ammonia yield rate of 40.67 μg h⁻¹ cm⁻² and a Faradaic efficiency of 24.9%. - The findings were published in September 2026 in eScience. - The DOI for the paper is 10.1016/j.esci.2025.100513.

The details: - The catalyst uses a mechanism the researchers call hydroxide-activated hydrogen spillover, or HAHS. - Controlled synthesis temperature introduced lattice distortion into Co(OH)₂. - The distortion elongated Co–O bonds and weakened nearby O–H bonds. - Hydrogen atoms from surface hydroxyl groups detached and entered the nitrogen reduction reaction directly. - Surface hydrogen vacancies formed during the process and were replenished by hydrogen species from the electrolyte. - The mechanism bypassed one elementary step in the usual associative pathway. - The shortcut accelerated intermediate turnover and reduced the competing hydrogen evolution reaction. - Density functional theory showed initial N₂ activation on Co(OH)₂ was nearly barrierless, with ΔG = 0.01 eV. - The catalyst remained structurally stable for 180 hours of continuous operation. - In situ electron spin resonance and isotope-labeled differential electrochemical mass spectrometry supported the spillover and vacancy-formation mechanism.

Between the lines: - The result is less about one faster catalyst and more about a new reaction design strategy. - The team’s approach turns a long-standing problem in electrocatalysis into a controllable materials-engineering question. - If the mechanism scales, it could lower the barrier to distributed ammonia production powered by renewable electricity. - The study also suggests the same lattice-engineering idea could apply to other difficult multi-step electrochemical reactions.

What's next: - The key test is whether the catalyst can hold its performance under longer, larger-scale operating conditions. - Further development will need to show whether the HAHS strategy can be translated into practical reactor systems. - Broader adoption would depend on cost, durability and integration with renewable power.

The bottom line: - The study offers a new catalytic route that could make green ammonia much more practical by simplifying nitrogen activation at ambient conditions.