Japanese researchers unveil a 3D system for producing green ammonia

Saturday 07 - 11:20

By: Dakir Madiha

Japanese researchers unveil a 3D system for producing green ammonia

Researchers in Japan and the United States have developed new methods to convert nitrate pollution into ammonia, opening potential alternatives to the century old Haber Bosch process, which is responsible for roughly 2 percent of global greenhouse gas emissions.

A team at Tohoku University has introduced a three dimensional covalent organic framework known as TU 82 that demonstrates high efficiency in the electrochemical conversion of nitrates into ammonia. The system achieved a faradaic efficiency of 88.1 percent and an ammonia production rate of 2.87 milligrams per hour per square centimeter. Published on February 2 in the Journal of Materials Chemistry A, the study marks the first successful use of three dimensional covalent organic frameworks for this reaction, surpassing the two dimensional structures that have dominated the field to date.

The Tohoku researchers designed the material by embedding atomically dispersed iron active sites within a complex porous network featuring an eight plus two connectivity pattern. This three dimensional architecture enhances mass transport and improves access to catalytic sites compared with layered two dimensional systems. According to the research team, the precise topological design and site specific metal coordination allow the structure to expose uniform catalytic centers optimized for nitrate to ammonia conversion.

Parallel work in the United States has produced similarly promising results. Scientists at Rutgers University reported in the Journal of Colloid and Interface Science a dual metal catalyst combining iron and cobalt that achieved nearly complete conversion of nitrates into ammonia. In this cooperative system, iron sites capture and activate nitrate molecules while cobalt sites split water to supply the hydrogen required for the reaction. The researchers highlighted the broader implications of this approach, suggesting it could reshape how water treatment and ammonia production are conceived by reframing nitrate pollution as a valuable resource rather than solely an environmental burden.

Together, these advances address two closely linked environmental challenges. Conventional ammonia production through the Haber Bosch process requires temperatures around 500 degrees Celsius and pressures up to 200 atmospheres, consuming about 1 percent of total global energy output. At the same time, nitrate contamination from agricultural runoff and industrial discharge threatens water resources worldwide, contributing to algal blooms and posing health risks such as methemoglobinemia.

Electrochemical nitrate reduction operates under ambient conditions while simultaneously removing a harmful pollutant. Researchers describe it as a potentially powerful platform for sustainable nitrogen cycle electrocatalysis. However, the work remains at the laboratory scale. Significant hurdles must still be overcome, including proving the long term stability of the catalysts and scaling the systems to match the output of existing ammonia infrastructure that supports nearly half of global food production.