Transfer hydrogenation reactions over single-atom catalysts
image: A variety of hydrogen sources (e.g., water, alcohols, formic acid, etc.) can be used in the reported SACs for TH. They are also capable of performing a variety of hydrogenation reactions.
Credit: © The Author(s) 2025. Published by Tsinghua University Press.
In a landmark review published in Nano Research, scientists from Wenzhou University highlight the transformative potential of single-atom catalysts (SACs) in advancing transfer hydrogenation (TH) reactions, a safer, more sustainable alternative to traditional hydrogenation processes. By synthesizing and analyzing SACs across various hydrogen sources, the study underscores how these nanoscale catalysts could revolutionize industries from pharmaceuticals to renewable energy.
“Transfer hydrogenation (TH) is regarded as the promising alternative as it replacing the H2 gas with safe, readily available and inexpensive hydrogen donors as the hydrogen source,” explained by Professor Jian Zhang, the study’s corresponding author, “The property of catalysts is vital to promote TH, and it is necessary to clearly understand the relationship between the structural character of catalysts and their performance for TH towards the rational design of better-performing catalysts.”
SACs, which disperse metal atoms individually on a support material, achieve 100% atomic efficiency, unlike conventional nanoparticle catalysts that waste active materials and suffer from uneven performance. This makes them ideal for TH, where fine-tuning interactions between catalysts, hydrogen sources, and substrates is critical.
The review categorizes TH reactions using SACs based on hydrogen sources, revealing how the catalysts’ atomic coordination and electronic properties directly influence performance. For example:
- Ammonia Borane: Pt-SACs with a Pt-S3 structure showed exceptional activity in nitroarene hydrogenation, achieving turnover frequencies (TOF) up to 8000 h-1. Cu-SACs with pyrrolic-N coordination enabled selective quinoline hydrogenation with 94% yield under mild conditions.
- Hydrazine Hydrate: Fe-SACs with Fe-N4 sites demonstrated high efficiency in reducing nitrobenzene to aniline, with a TOF of 748 h-1, outperforming traditional nanoparticle catalysts.
- Formic Acid: Co-SACs with Co-N3S1 structures promoted efficient hydrogenation of N-heterocycles, showcasing the impact of heteroatom doping on electron density and reaction kinetics.
- Alcohols and Water: Ni-SACs and Fe-SACs enabled selective hydrogenation of biomass-derived compounds like furfural, highlighting SACs’ potential in sustainable biomass valorization.
“The coordination structures make them exhibit unique electronic and geometric characters for displaying preeminent catalytic behavior and also provide straightforward and diverse regulation approaches for the performance optimization,” said Zhiyi Liu, first author of the review.
While SACs have shown promise, the team identifies key frontiers for innovation:
- Broader Substrate Scope: Current applications focus on limited unsaturated groups (alkynes, nitro compounds, carbonyls). Expanding to more complex molecules like polycyclic aromatics or bioactive compounds could unlock new synthetic pathways in drug discovery.
- Greener Hydrogen Sources: Water and ammonia hydroxide are ideal due to their abundance and low cost, but their low reactivity requires SACs with enhanced activation capabilities.
- Electro- and Photocatalysis Integration: Combining SACs with electrochemical or photocatalytic techniques could leverage clean energy inputs (electricity, light) to drive TH reactions, reducing reliance on thermal processes and further lowering environmental impact.
The ultimate vision is to create versatile, cost-effective SACs for industrial-scale applications:
- Pharmaceuticals: Selective hydrogenation of nitroaromatics and heterocycles to synthesize drug intermediates with minimal byproducts.
- Biomass Conversion: Efficiently transforming biomass-derived molecules like furfural into high-value chemicals (e.g., furfuryl alcohol) for biofuels and polymers.
- Electrochemical Synthesis: Using water as a hydrogen source in flow reactors for sustainable, scalable production of fine chemicals.
As researchers refine synthesis methods and deepen their understanding of structure-activity relationships, SACs are poised to make hydrogenation safer, more efficient, and environmentally friendly—paving the way for a sustainable chemical industry.
Citation: Liu, Z., Ge, Y., Lv, A., Zhang, J., & Zhang, J. (2025). Transfer hydrogenation reactions over single-atom catalysts. Nano Research. DOI: 10.26599/NR.2025.94907436
About the Authors
Jian Zhang: Doctor, M.S. Tutor, Associate Professor. B.S. and M.S. from Wuhan University, Ph.D. and Postdoctoral from Tsinghua University. His research field is heterogeneous catalytic organic synthesis chemistry which is based on the innovative design and precise synthesis of single-atom, cluster, and nano-catalytic materials. Besides, he carries out the methodological and mechanistic studies of organic synthesis by thermal and electrocatalysis, and analyzes the structure-performance relationship with heterogeneous catalysts in catalytic reaction process. So far, he has published more than 30 SCI papers in international academic journals, including a total of 12 academic papers as first and corresponding authors, including Nat. Commun., Chem, J. Am. Chem. Soc., Adv. Mater., Chem. Sci., Nano Res., Nano Lett., Small, ACS Appl. Mater. Interfaces, Inorg. Chem. etc. In 2019, he was selected for the China Postdoctoral Innovative Talent Support Program, and in 2022, he was selected for the Wenzhou Ouyue Haizhi Program. https://www.x-mol.com/groups/jianzhang-wzu
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 7,000 articles. In 2024 InCites Journal Citation Reports, its 2024 IF is 9.0 (8.7, 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.