The escalating concentration of atmospheric CO 2 , driven by fossil fuel consumption, poses a significant environmental challenge. Electrochemical CO₂ reduction (CO 2 RR) offers a promising pathway to convert this greenhouse gas into valuable fuels and chemicals. Among these, carbon monoxide (CO) is a high-value industrial feedstock. While single-atom iron catalysts (Fe-N-C) have shown great promise for this conversion due to their high selectivity and low cost, their practical application has been severely hindered by an inherent conflict: enhancing their activity often compromises their long-term operational stability.
A team of material scientists led by Dr. Chaoyun Ma from Xinjiang University and Prof. Hao Jiang from East China University of Science and Technology has introduced an innovative strategy to resolve this dilemma. Their findings, published in the journal Nano Research on May 19, describe a new catalyst that simultaneously achieves high activity and remarkable stability for CO 2 -to-CO conversion.
The team employed a single-precursor in-situ sulfidation strategy to construct a catalyst, named ZnS@Fe-NSC, which features atomically dispersed iron active sites (Fe-N 4 ) synergistically modified by sulfur atoms and adjacent zinc sulfide (ZnS) nanoparticles. This unique architecture was achieved by a one-step pyrolysis of an iron-doped zinc-based metal-organic framework (ZIF-8) in the presence of a sulfate source.
"Our approach elegantly combines two critical modifications into a single synthetic step," said Dr. Chaoyun Ma, the corresponding author of the study. "The sulfur doping optimizes the electronic structure of the iron sites to lower the energy barrier for the key reaction intermediate (*COOH), thereby enhancing the intrinsic activity. Meanwhile, the adjacent ZnS nanoparticles act as electron donors, strengthening the iron-nitrogen bonds and creating a protective effect that prevents the iron atoms from leaching out during the reaction."
The results were striking. In electrochemical tests, the ZnS@Fe-NSC catalyst achieved a CO Faradaic efficiency (a measure of selectivity) of 99.53% at a low overpotential of -0.58 V versus reversible hydrogen electrode (RHE). More importantly, it maintained over 90% selectivity for 30 hours of continuous operation. In stark contrast, the control catalysts without the synergistic modification exhibited rapid degradation, losing more than half of their initial activity within the same timeframe. The team found that the ZnS nanoparticles reduced iron leaching by over 20-fold.
“This work effectively breaks the activity-stability trade-off that has long plagued this class of materials,” added Prof. Hao Jiang. "We were able to pinpoint the mechanism: the ZnS nanoparticles donate electrons to the iron centers, which both speeds up the CO 2 conversion and significantly strengthens the anchoring of the iron atoms, preventing them from being washed away."
To demonstrate its practical potential, the researchers integrated the ZnS@Fe-NSC catalyst into a rechargeable Zn- CO 2 battery. The battery delivered a peak power density of 6.2 mW cm -2 and operated stably for 125 hours—a performance that surpasses most reported Fe-based single-atom catalysts—and was even able to power a small light-emitting diode (LED).
This work provides a powerful new design principle for developing next-generation single-atom catalysts that are not only highly active but also durable enough for real-world applications in energy conversion and beyond. The team plans to further explore this synergistic design strategy to develop catalysts for other critical electrochemical processes, such as water splitting and oxygen reduction for fuel cells.
Other contributors include Yang Li, Yuemei Liu, Junhong Ma from Xinjiang University; Yang Yuan from Guangyuan China Nuclear Vocational and Technical College; and Xiaojun Lv from North China Electric Power University.
This work was supported by the National Natural Science Foundation of China, the "Tianchi Talent" Introduction Program of Xinjiang Uygur Autonomous Region, and other funding sources.
DOI Link:
https://doi.org/10.26599/NR.2026.94908640
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.
Nano Research
Synergistic design overcomes activity-stability trade-off in iron-based catalysts for efficient CO₂ conversion
19-May-2026