Tohoku University Synthesizes Single-Atom Ruthenium Catalyst with 11% Metal Loading
Chemists have developed an ordered carbon framework holding up to 11 wt% isolated ruthenium atoms for CO₂ reduction in laboratory tests.
Researchers at Tohoku University, in collaboration with the University of Tsukuba, Kyoto University, and The University of Osaka, have developed a synthesis method for high-density ruthenium single-atom catalysts 
tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. The findings were published in Angewandte Chemie International Edition on September 3, 2026, according to tohoku.ac.jp. The team addressed the issue of metal atom aggregation by creating molecular precursors that anchor individual ruthenium atoms into an organized porous carbon framework.
Traditional single-atom catalysts rarely exceed 2 wt% metal loading because isolated atoms tend to aggregate into larger particles at higher concentrations tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. To overcome this limitation, the authors designed flexible precursor molecules based on polypyridyl coordination motifs capable of accommodating ruthenium centers. Thermal treatment of these precursors yielded an ordered carbonaceous matrix that stabilized isolated metal sites at concentrations reaching up to 11% by weight.
Catalytic Performance and Selectivity
In laboratory evaluations, the synthesized catalyst converted carbon dioxide into formic acid with a selectivity exceeding 99% tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. This high selectivity prevented the formation of unwanted byproducts during the chemical reaction. Testing demonstrated that the carbon framework and active metal centers remained stable across repeated cycles.
Microscopic and structural analyses revealed no signs of ruthenium clustering or structural degradation of the porous support after cycling tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. The team reported that the coordinated single-atom architecture preserved active reaction sites despite the elevated metal loading.
Potential Applications Across Precious Metals
The authors stated that this fabrication technique enables more efficient utilization of scarce catalytic metals in chemical manufacturing tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. Formic acid produced via this route serves as an industrial feed chemical and hydrogen carrier.
Following the successful implementation with ruthenium, the research group plans to test the coordination approach on other precious metals tohoku.ac.jptohoku.ac.jptohoku.ac.jpOpen source ↗. Future targets include the stabilization of platinum, palladium, and iridium within identical structured carbon frameworks.
